ALBERT

Description: In whatever state of bonding – whether covalent to an organic residue or a heteroatom, or polar to ionic in contact with a metal – the azide moiety N 3 is characterized by its high potential of reactivity which essentially manifests itself in two basic processes: the elimination of dinitrogen and the entry into 1, 3-dipolar cycloadditions with suitable dipolarophiles, the latter of which clearly predominates the chemistry of azide, also that of its metal compounds. In a preceding review entitled “Part I – Metal Azides: Overview, General Trends and Recent Developments” which was meant to lay the foundations for the present paper, these and other reactions have already been touched upon. The present review – Part II – now focusses in great detail on the formation of five-membered heterocycles – tetrazol(at)es, triazol(at)es, triazolin(at)es, thiatriazol(at)es, etc. as well as various consecutive products – from azide and nitriles, isocyanides, alkynes, alkenes and heteroallenes (CS 2 , RN=C=S) in the ligand sphere of the metal. Generally, these [3+2]-cycloadditions are found to proceed under much milder conditions in comparison with the strictly organic case whose triumphant progress since the 1960s is intimately bound up with the name of Huisgen. Mechanistic considerations on the matter are presented. A secondary aspect still occupying quite a part of the discussion is concerned with the role of metals in [3+2]-cycloadditions particularly of the highly topical “click”-type, e.g. (CuAAC), (RuAAC). Likewise, a short chapter deals with the question of pentazol(at)e (N 5 – ) which according to numerous theoretical studies could well be stabilized and isolated in combination with metals, e.g., in the form of azametallocenes. A last chapter is devoted to a cursory survey of related systems, in particular fulminato complexes, metall o nitrile ylides and metall o nitrile imines, in which the metal acts as a substituent on the 1, 3-dipole (metall o -1, 3-dipole). Other systems with a metal substituent on the dipolarophile (metall o -dipolarophile), or, with metal itself in the three- (two-) atom arrangement constituting the dipole (dipolarophile) [metall a -1, 3-dipole, metall a -dipolarophile] are only quoted by way of example.

Description: The organically-templated uranyl selenite, (H 2 en)[(UO 2 )(SeO 3 )(HSeO 3 )](NO 3 ) · 0.5H 2 O ( 1 ) (en = 1,2-ethylenediamine) was synthesized and characterized by elemental analyses, IR spectroscopy, TG, and single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic system, space group Pbca , with a = 13.170(3) Å, b = 11.055(2) Å, c = 18.009(4) Å, V = 2621.8(9) Å 3 , M = 1316.19, Z = 4, D cal = 3.334 g · cm –3 , μ (Mo- K α ) = 17.998 mm –1 , GOF = 1.059, R 1 = 0.0263, wR 2 = 0.0532 [ I 〉2 σ ( I )]. The X-ray diffraction analysis reveals that compound 1 has a three-dimensional (3D) supramolecular structure. It contains negatively charged [UO 2 (HSeO 3 )(SeO 3 )] – inorganic anion layers and is balanced by [H 2 en] 2+ cations and NO 3 – anions located in the interlayers. Furthermore, the photoluminescence properties of 1 were investigated.

Description: The cover picture shows two types of the phosphanegold(I) cluster cations and Keggin polyoxometalate (POM) anions coordinated by two mononuclear phosphanegold(I) cations. These intercluster compounds are formed during carboxylate elimination of monomeric phosphanegold(I) carboxylate precursors in the presence of the POM. The structures of phosphanegold(I) cluster cations show different dimerization arrangements by inter-cationic aurophilic interactions in crossed-edge arrangement (tetrahedral Au 4 structure) or parallel-edge arrangement (rectangular Au 4 structure). This structural difference depends upon the p -substituent, F or Cl, on the aryl group of the triarylphosphanes. Mononulcear phosphanegold(I) cations linked to the POM indicate a transient state in the formation of the phosphanegold(I) cluster cations. More details are discussed in the article by K. Nomiya et al. on pp. 1688ff.

Description: Deprotonation of 1,2-bis(neopentylamino)benzene ( 1 ) with an excess of KH in tetrahydrofuran (thf) yields the singly metalated derivative [(thf)K{C 6 H 4 -1-(NH-CH 2 t Bu)-2-(N-CH 2 t Bu)}] ( 2a ). Performance of the metalation reaction in tetrahydropyran (thp) leads to formation of [(thp) 2 K{C 6 H 4 -1-(NH-CH 2 t Bu)-2-(N-CH 2 t Bu)}] ( 2b ). The second amino group of 2a can be lithiated by butyllithium yielding heterobimetallic [(thf) 2 LiK{C 6 H 4 -1,2-(N-CH 2 t Bu) 2 }] ( 3 ). The structures demonstrate that ethers as well as aromatic π systems represent suitable bases for the rather soft potassium ions. Intermolecular potassium π interactions lead to the formation of strands in the crystalline state. For complex 2a , a dynamic exchange process of the N-bound hydrogen atom with an energy barrier of 45.6 kJ · mol –1 is observed in [D 8 ]THF solution. Heterobimetallic 3 also shows a temperature-dependent dynamic behavior that gives rise to splitting of the methylene and aromatic resonances suggesting overlying metal exchange and aggregation equilibria.

Description: Abstract. Three cyanide-bridged compounds Zn(4, 4′-bpy)(H 2 O) 2 M (CN) 4 (4, 4′-bpy = 4, 4′-bipyridine; M = Ni ( 1 ), Pd ( 2 ), Pt ( 3 )) were synthesized by self-assembly of Zn 2+ ions, pillar ligands 4, 4′-bpy and [ M (CN) 4 ] 2– . Single-crystal X-ray diffraction analysis revealed that compounds 1 – 3 are isostructural and belong to monoclinic space group C 2/ c . The zinc atom is located in a distorted octahedral arrangement, whereas the central nickel atom adopts square-planar arrangement. The central Zn and Ni atoms are linked alternatingly through two cis cyanide groups, generating zigzag chains. The adjacent chains are further connected along two different directions by 4, 4′-bpy ligands to form a three-dimensional framework. Thermal expansion (TE) analyses of compounds 1 – 3 showed that both a and c axes are positive TE coefficients, compared to the near zero TE one along the b axis.

Description: The title compound Ca 3 [BN 2 ]I 3 was obtained from reactions of mixtures of the starting materials Ca 3 [BN 2 ] 2 and CaI 2 in a 1:4 ratio in sealed Nb tubes at 1223 K. The crystal structure was solved from powder synchrotron diffraction data. Ca 3 [BN 2 ]I 3 is the first example of a halide-rich nitridoborate crystallizing in the rhombohedral space group R 32 [no. 155, Pearson code: hR 96; Z = 12; a = 16.70491(2) Å, c = 12.41024(2) Å]. The crystal structure is built up by two interpenetrating networks of condensed edge-sharing [BN 2 ]@Ca 6 and [□]@I 6 trigonal antiprisms (□ = void). In Ca 3 [BN 2 ]I 3 two crystallograhically distinct [BN 2 ] 3– anions are present with d (B1–N) = 1.393(2) Å and d (B2–N) = 1.369(9) Å. Their bond angles are practically linear, varying only slightly: N–B1–N = 179(1)° and N–B2–N = 180°. Vibrational spectra were interpreted based on the D ∞ h symmetry of the discrete linear [N–B–N] 3– moieties, considering the site symmetry reduction and the presence of two distinct [BN 2 ] 3– groups.

Description: Three complexes [Ca(ClO 4 )(H 2 O)Cu 5 (o-picHA-2H) 5 (H 2 O)]ClO 4 ( 1 ), [Pr(NO 3 ) 2 (py)Cu 5 (o-picHA-2H) 5 (py) 5 ]ClO 4 ( 2 ), and [Nd(NO 3 )(H 2 O)(py)Cu 5 (o-picHA-2H) 5 (py) 5 ](ClO 4 ) 2 · 5py ( 3 ) ( o -picHA = 2-picolinehydroxamic acid) were synthesized in order to retrace structural trends caused by the change of the ionic radius of the central metal ion as well as to assess the effect of the axial ligands on the arrangement of metallacrowns. The complexes were characterized by elemental analysis, ESI-mass spectrometry, IR spectroscopy, and single-crystal X-ray analysis. The heterometallic complexes have 15-MC-5 molecular topology with Ca II or Ln III ion in the center of the metallamacrocyclic cavity. The Ca–O and Ln –O bond lengths follow the trend of changes of the corresponding metal ionic radii. While the Ca II complex cation (without axial ligands) in 1 is almost flat, the Ln III containing cations in 2 and 3 have a “partially opened umbrella“ environment.

Description: Cadmium(II) based 2D coordination polymer [Cd(L1) 2 (DMF) 2 ] ( 1 ) (L1 = 4,5-dicyano-2-methylimidazolate, DMF = N,N ′-dimethylformamide) and 2D cobalt(II)-imidazolate framework [Co(L3) 4 ] ( 2 ) (L3 = 4,5-diamide-2-ethoxyimidazolate) were synthesized under solvothermal reaction conditions. The materials were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction measurement (PXRD) and single-crystal X-ray diffraction. Compound 1 has hexacoordinate Cd II ions and forms a zigzag chain-like coordination polymer structure, whereas compound 2 exhibits a 2D square grid type structure. The thermal stability analysis reveals that 2 showed an exceptional thermal stability up to 360 °C. Also, 2 maintained its fully crystalline integrity in boiling water as confirmed by PXRD. The solid state luminescent property of 1 was not observed at room temperature. Compound 2 showed an independent high spin central Co II atom.

Description: The amino substituted bidentate chelating ligand 2-amino-5-(2-pyridyl)-1,3,4-thiadiazole (H 2 L ) was used to prepare 3:1-type coordination compounds of iron(II), cobalt(II) and nickel(II). In the iron(II) perchlorate complex [Fe II (H 2 L ) 3 ](ClO 4 ) 2 ·0.6MeOH·0.9H 2 O a 1:1 mixture of mer and fac isomers is present whereas [Fe II (H 2 L ) 3 ](BF 4 ) 2 ·MeOH·H 2 O, [Co II (H 2 L ) 3 ](ClO 4 ) 2 ·2H 2 O and [Ni II (H 2 L ) 3 ](ClO 4 ) 2 ·MeOH·H 2 O feature merely mer derivatives. Moessbauer spectroscopy and variable temperature magnetic measurements revealed the [Fe II (H 2 L ) 3 ] 2+ complex core to exist in the low-spin state, whereas the [Co II (H 2 L ) 3 ] 2+ complex core resides in its high-spin state, even at very low temperatures.

Description: 1-(Furan-2-ylmethyl)-1 H -tetrazole (fmt), prepared by heterocyclization of furfurylamine with triethyl orthoformate and sodium azide, was found to react with copper(II) perchlorate, nitrate, and bromide giving complexes [Cu(fmt) 4 (H 2 O) 2 ](ClO 4 ) 2 , [Cu(fmt) 3 (NO 3 ) 2 (H 2 O)], and [Cu 2 (fmt) 4 Br 4 ], respectively. The obtained crystalline complexes and fmt were characterized by X-ray diffraction, thermal analyses, and IR spectroscopy. In the complexes, fmt acts as a monodentate ligand coordinated via the tetrazole ring N 4 atom. [Cu(fmt) 4 (H 2 O) 2 ](ClO 4 ) 2 comprises a mononuclear complex cation with an elongated CuN 4 O 2 octahedron. [Cu(fmt) 3 (NO 3 ) 2 (H 2 O)] presents a mononuclear complex, where the copper atom is in a heptacoordinate environment forming a considerably distorted pentagonal bipyramid. [Cu 2 (fmt) 4 Br 4 ] presents a centrosymmetric dinuclear bromido-bridged complex with a square pyramidal environment of copper atoms.

Description: Three copper(II) complexes, [Cu 2 (O 2 CC 4 H 3 O) 4 (H 2 O) 2 ] · H 2 O ( 1 ), {[Cu 2 (O 2 CC 4 H 3 O) 4 (bipy) 2 (H 2 O) 2 ] · 2H 2 O} n ( 2 ), and {[Cu(bpp) 2 (H 2 O)](O 2 CC 4 H 3 O) 2 · 7H 2 O} ( 3 ) [O 2 CC 4 H 3 O = 2-furanocarboxylate anion, bipy = 4, 4′-bipyridine, and bpp = 1, 3-bis(4-pyridyl)propane] were synthesized and their crystal and molecular structures were determined by single-crystal X-ray diffraction analysis. Compound 1 consists on bimetallic tetracarboxylate units exhibiting a common paddle wheel structure. The paddle wheel units are connected by hydrogen bonding along the crystallographic b axis and π–π stacking interactions between the furano rings along the crystallographic c axis, giving rise to a 2D supramolecular array. Compounds 2 and 3 were made up in the presence of 4, 4′-bipyridine and 1, 3-bis(4-pyridyl)propane ligands, respectively, to produce 1D polymeric chains by metal-ligand interactions. The presence of other weak non-covalent interactions in these compounds extends the systems dimensionality to form 3D supramolecular networks.

Description: The double molybdate Rb 2 Ba(MoO 4 ) 2 was synthesized by high temperature solid-state reaction. According to the single-crystal X-ray diffraction structure determination, it is isostructural to the mineral Palmierite K 2 Pb(SO 4 ) 2 in the trigonal space group R m . Its structure can be described as layers of MoO 4 tetrahedra corner-sharing with distorted BaO 6 octahedra, while the layers are separated by bi-layers of rubidium cations in 10-coordinate environment. UV/Vis-NIR spectroscopy measurement indicates that Rb 2 Ba(MoO 4 ) 2 has an indirect bandgap of 4.40 eV, comparable to the calculated value 4.21 eV. The DSC test demonstrates the melting point and incongruent melting characteristic of the title compound. About seven narrow Raman lines were observed in the Raman spectrum recorded for Rb 2 Ba(MoO 4 ) 2 powder sample.

Description: Nucleophilic substitution of the ethoxy substituent in the Fischer carbene complex (ethoxy)(ferrocenyl)carbene(pentacarbonyl)chromium(0) ( 1 ) by ferrocenyl amide [Fc-NH] – [2 - H] – gives the hetero trimetallic complex (aminoferrocenyl)(ferrocenyl)carbene (pentacarbonyl)chromium(0) ( 3 ). As the Cr(CO) 5 fragment is isolobal to oxygen or sulfur 3 can be viewed as an isolobal metallo analogue to diferrocenylamide (Fc)(FcNH)C=O ( 4 ) and diferrocenylthioamide (Fc)(FcNH)C=S ( 5 ). The impact of the formal replacement of O/S by Cr(CO) 5 in 3 is studied with respect to steric and electronic consequences as well as reactivity by spectroscopic, diffraction, electrochemical and theoretical methods.

Description: Novel dinuclear silver(I) and gold(I) complexes with 4,5-disubstituted diimidazol-2,2′-diylidene ligands featuring a methylene or 1,3-propylene bridge between the two N-heterocyclic carbene moieties were prepared and characterized. The substituents in the backbone of the heterocyclic ring are electron-withdrawing groups (chlorine atoms or cyanide groups) and their effect on the spectroscopic and structural properties of the resulting complexes was analyzed and discussed.

Description: The solid state reaction of WCl 6 with copper powder and a reactive source of carbon leads to a new trigonal prismatic carbon-centered tungsten cluster containing copper ions. Cu[W 6 CCl 18 ] dissolves in organic solvents (dimethylsulfoxide, acetone), resulting in two air stable products Cu(C 2 H 6 OS) 6 [W 6 CCl 18 ] and Cu(C 2 H 6 OS) 4 [W 6 CCl 18 ] 2 . Both of them contain carbon-centered trigonal prismatic tungsten clusters [W 6 CCl 18 ] n – ( n = 1, 2) and Jahn-Teller distorted octahedral copper(II) ions. Crystal structures of all compounds were investigated by single-crystal X-ray diffraction. The presence of carbon as an interstitial atom in the cluster is confirmed by nuclear magnetic resonance spectroscopy.

Description: Nano-grained CoSb 3 was prepared by melt-spinning and subsequent spark plasma sintering. The phonon thermal conductivity of skutterudites is known to be sensitive to the kind and the amount of guest atoms. Thus, unfilled CoSb 3 can serve as model compound to study the impact of a nanostructure on the thermoelectric properties, especially the phonon thermal conductivity. Therefore, a series of materials was prepared differing only by the cooling speed during the quenching procedure. In contrast to clathrates, the microstructure of meltspun CoSb 3 was found to be sensitive to the cooling speed. Although the phonon thermal conductivity, studied by means of Flash and 3 ω measurements, was found to be correlated with the grain size, the bulk density of the sintered materials had an even stronger impact. Interestingly, the reduced bulk density did not result in an increased electrical resistivity. The influence of Sb and CoSb 2 as foreign phase on the electronic properties of CoSb 3 was revealed by a multi-band Hall effect analysis. While CoSb 2 increases the charge carrier density, the influence of the highly mobile charge carriers introduced by elemental Sb on the thermoelectric properties of the composite offer an interesting perspective for the preparation of efficient thermoelectric composite materials.

Description: A series of transition metal coordination complexes, {[Cu(3-Sptta) 2 ] · 1/2H 2 O} n ( 1 ), {[Cd(3-Sptta) 2 ] · 1/2H 2 O} n ( 2 ), [Zn(3-Sptta) 2 (H 2 O) 4 ] ( 3 ), and [Co(3-Sptta) 2 (H 2 O) 4 ] ( 4 ) were synthesized under solvothermal and solvent evaporation conditions using the newly designed heterocyclic N/NS carboxylate ligand [2-(3-pyridyl)-1,3,4-thiadiazole-5-]-thio-acetate (3-Sptta) as a main building block. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses and IR spectroscopy. The four complexes exhibit structural diversity: complexes 1 and 2 exhibit similar 2D “wave-like” double-layer framework with two shares of mutually parallel left-handed and right-handed helical chains, whereas 3 and 4 present mononuclear structures. Moreover, the thermal stabilities of complexes 1 – 4 were investigated. The luminescent properties of complexes 2 , 3 and the free ligand were also studied.

Description: A mixed-valence Mn complex {[Mn II Mn III (HL) 2 (4,4′-bpy)(H 2 O) 2 ] · (ClO 4 )(DMF) 3 (4,4′-bpy) 0.5 } n ( 1 ) [H 2 L = 3-(2-phenol)-5-(pyridin-2-yl)-1,2,4-triazole] was synthesized and characterized by X-ray single-crystal structure analysis and magnetic susceptibility. Single-crystal X-ray analysis revealed that complex 1 has a dinuclear core, in which adjacent central Mn III atoms are linked by 4,4′-bipyridine to form an infinite one-dimensional (1D) molecular configuration. According to the Mn surrounding bond lengths and bond valence sum (BVS) calculations, we demonstrated that the Mn atom coordinated to the pyridine N atoms is in the +2 oxidation state, while another Mn atom coordinated to the phenolic oxygen atoms is in the +3 oxidation state. Magnetic susceptibility data of the complex 1 indicate that the ferromagnetic interaction dominates in this complex.

Description: The reactivity of the 2-imidazolecarboxaldiimine of triethylenetetraamine (H2imida) towards divalent manganese, cobalt, and nickel ions differs. It forms a cationic nickel(II) complex by acting as a hexa-dentate ligand, whereas the cobalt(II) complex formation took place by deprotonation of the H2imida forming a neutral complex with imida. Deprotonation of the ligand by H2imida by cobalt(II) ions caused quenching of the fluorescence emission at 312 nm, such a quenching effect was not observed with the nickel ions. On the other hand, a mononuclear manganese(II) complex of a new tetradentate ligand was formed by manganese(II) assisted intramolecular cyclization reactions of H2imida.

Description: A new dinuclear mixed-valence compound [Mn II Mn III (bttpnol)(O 2 C–C 6 H 4 –NO 2 ) 2 ]ClO 4 was synthesized by using the asymmetric heptadentate ligand N -(2-hydroxybenzyl)- N,N ′, N ′-tris(2-pyridylmethyl)-1,3-diaminopropan-2-ol (H 2 btppnol). One central manganese atom assumes N 3 O 3 and the other N 2 O 4 coordination sphere. Both manganese ions are bridged by the alkoxy-group of the dinucleating ligand and two bidentate carboxylate groups of the nitrobenzoate ligands. The structural data show clearly that Mn III prefers the more oxygen rich donor set. Cyclic voltammetry measurements reveal that the mixed-valence state Mn 2 (II,III) could be reduced to Mn 2 (II,II) at E 1/2 (1) = –0.53 V and oxidized to Mn 2 (III,III) at E 1/2 (2) = 0.52 V (vs. ferrocene). Measurements of the magnetic susceptibility reveal a weak antiferromagnetic coupling with J = –8.5 cm –1 . The mixed valence state was additionally confirmed by EPR spectroscopy showing the hyperfine signal of the S = 1/2 state of Mn 2 (II,III).

Description: Three lanthanide complexes with the ligand 4-sulfophthalate (sp 3– ), [ Ln (H 2 O) 2 (sp)] n [ Ln = Dy ( 1 ), Tb ( 2 ), and Er ( 3 )], were solvo-/hydrothermally synthesized by changing the rare earth cations, and were characterized structurally and photophysically. Complexes 1 – 3 are isostructural, exhibiting a two-dimensional layered structure with centrosymmetric dinuclear subunits infinitely extended by 4-connected sp 3– connectors. Photoluminescence spectra of 1 – 3 demonstrate that anionic sp 3– ligand can serve as a functionalized chromophore to sensitize the luminescent emission of the lanthanide ion, suggesting that the sp 3– -involved lanthanide complexes can be used as novel optical materials.

Description: N -(Diferrocenylmethylene)anilines Fc 2 C=N-4-C 6 H 4 – R [ 3a R = CF 3 ; 3b R = Cl; 3c R = H; 3d R = CH 3 ; 3e R = OCH 3 ; Fc = Fe(η 5 -C 5 H 4 )(η 5 -C 5 H 5 )] with different electron-donating or -withdrawing functionalities were synthesized by a Schiff base reaction of substituted anilines H 2 N-4-C 6 H 4 - R ( 2a – 2e ) with diferrocenyl ketone ( 1 ). Within variable temperature NMR experiments activation enthalpies between 68.1 and 72.3 kJ · mol –1 for an E / Z exchange reaction of the imines were determined. It could be shown that the inversion barrier depends on the nature of the substituent R . Furthermore, electrochemical measurements were performed, demonstrating that the ferrocenyl units are oxidized separately. The electron density at the nitrogen atom is influenced by the electronic nature of the aniline groups R thus giving rise to varying attractive electrostatic interactions to the ferrocenium units. This results in decreasing redox separations for the ferrocenyl oxidation with a decreasing electron-withdrawing character of the anilines. Spectroelectrochemical measurements confirmed that the redox separations are mainly caused by electrostatic interactions as no electronic metal–metal coupling is observed. For 3a , b , d , e the molecular structure in solid state was determined by single-crystal X-ray diffractometry. In all compounds different forms of π–π interactions occur. Compound 3a shows a complex network of parallel- and T -shaped π–π interactions, whereas 3d is forming 5- and 6-membered cycles.

Description: The first silver rhodizonate and overall fourth transition metal rhodizonate complex is presented. The title compound shows a so far unobserved coordination mode of the rhodizonate ligand, which is atypically distorted from planarity. The structure discussion is accompanied by a thorough literature review of the hitherto structurally characterized rhodizonate salts and complexes.

Description: Three two-dimensional (2D) coordination complexes, namely [Ca 2 (HL) 2 (H 2 O) 5 ] n · 2 n H 2 O ( 1 ), [Sr(HL)(H 2 O) 3 ] n · n H 2 O ( 2 ), and [Ba(HL)(H 2 O) 3 ] n · n H 2 O ( 3 ) [H 3 L = 3-(3-carboxy-phenoxy) phthalic acid], were synthesized by using the ligand H 3 L and alkaline earth metals. Structural analysis reveals that the structures of complexes 1 – 3 can be described as 2D networks with the point (Schälfli) symbol for net: {3 12 · 4 14 · 5 2 } topology. Additionally, the thermal stability and solid-state luminescent properties of compounds 1 – 3 were investigated at room temperature. The quantum yield (QY) of compound 2 is 10.75 %, which is much higher than the QY of the free H 3 L ligand (QY H3L 〈 1 %).

Description: The 2D coordination polymer {[Cu 32 ( pa ) 24 (μ 2 -OH) 8 (μ 3 -OH) 8 ( bibp ) 8 ] · (CH 3 OH) 3 (H 2 O) 5 } ∞ was prepared by the solvothermal reaction of Cu(NO 3 ) 2 · 3H 2 O with phthalic acid (H 2 pa ) and 4,4′-bis(imidazol-1-yl)biphenyl ( bibp ). The Cu II ions show five different kinds of coordination environments, which are all connected by the pa 2– ion into an interesting 1D carboxylate-copper chain with rare icosacopper and tetracopper clusters. The 1D chain is further bridged by the bibp ligand to form a 2D layer, which could be viewed as an unprecedented (4,4) lattice based on rectangular and butterfly-shaped tetracopper clusters with the ratio of 2:6. The magnetic properties were studied, and the results show antiferromagnetic interaction in the complicated 1D chain.

Description: The synthesis, spectroscopic, electrochemical, magnetic, and structural characterization of the dinuclear series of complexes [(MOM 2 tom Me ){ M II Cl 2 } 2 ] ( M II = Zn II , Cu II , Ni II , Co II , Fe II ) and, for comparison, the structure of the complex [(MOM 2 tom){Zn II Cl 2 } 2 ] are presented. The metal ions are five-coordinate in N 3 Cl 2 environments. The coordination polyhedra are evaluated in the solid-state by single-crystal X-ray crystallography and in solution by UV/Vis/NIR spectroscopy for the Cu II and Fe II complexes. All complexes exhibit a ligand-centered irreversible oxidation in the range 1.17–1.40 V vs. Fc + /Fc, whereas the complexes with Fe II , Co II , and Ni II exhibit additional reversible metal-centered oxidations of 0.09, 0.70, and 0.87 V vs. Fc + /Fc, respectively. The coordination of the chloride ligands saturates the Lewis-acidity of the metal ions so that the MOM groups are not cleaved. Bands at 1161 and 1020 cm –1 in the FT-IR spectra are a signature for the presence of the MOM groups. Reaction with copper(II) acetate at room temperature results in the complex [(MOM 2 tom Me ){Cu II (OAc) 2 } 2 ] while the reaction at 50 °C for several hours resulted in the simultaneous MOM cleavage and complexation and thus isolation of [(tom Me ){Cu(OAc)} 2 ]. This successful synthetic route will be applied to establish a series of [(tom Me ){ M (OAc)} 2 ] with different metal ions in order to compare their DNA binding ability and cytotoxicity to cancer cells to that of the copper(II) complex.

Description: All the known polymorphs of Al(OH) 3 comprise a stacking of charge neutral layers having the composition [Al 2/3 □ 1/3 (OH) 2 ] (□: cation vacancy) and designated by the symbol P. Employing a single Al(OH) 3 layer (layer group p 12 1 / a 1) as a structural synthon, the energy profile computed for the translations of P and ( : mirror image of P) layers relative to each other within a bilayer model, not only show minima corresponding to the four known polymorphs of Al(OH) 3 but also predict three new polymorphs with energy minima at the stacking vectors (7/10, 5/18, 1) (polymorph B 1), (1/2, 0, 1) (polymorph B 2) and (2/5, 1/9, 1) (polymorph B 4). Of these B 1 and B 2 are 0.30 eV and 0.23 eV below the energy of bayerite ( B 3), but 0.30 eV and 0.37 eV above the global minimum which corresponds to gibbsite. B 4 is only 0.08 eV above the energy of bayerite. This quantitative structural synthon approach offers B 1, B 2, and B 4 as legitimate targets for future synthetic efforts.

Description: The coordination polymers {[Cd( o -BDC-Cl 4 )(H 2 O) 2 ]·EtOH} n ( 1 ) and {[Cd( p -BDC-Cl 4 )(DMF)]·H 2 O} n ( 2 ) ( o -BDC-Cl 4 = tetrachlorophthalate and p -BDC-Cl 4 = tetrachloroterephthalate) were synthesized in different solvents using two isomeric tetrachlorinated benzenedicarboxylic acids. Complex 1 based on o -BDC-Cl 4 features an extremely rare 2D trinodal (3,4,6)-connected network constructed by the combination of 1D [Cd-H 2 O] n chains and 1D [Cd 2 ( o -BDC-Cl 4 ) 2 ] n loop-like motifs. Complex 2 based on p -BDC-Cl 4 has a 3D framework and shows a uninodal 4-connected sra topology. Complexes 1 and 2 were characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction and thermogravimetric (TG) analyses. The photoluminescence of 1 and 2 were investigated in the solid state at room temperature.

Description: The N–H bond activation product [PNP]-Fe I (PMe 3 ) 2 ( 2 ) was obtained at room temperature by the reaction of diphosphinito [PNP] pincer ligand ((Ph 2 P(C 6 H 4 )) 2 NH ( 1 )) with Fe(PMe 3 ) 4 . Treatment of 1 with Co(PMe 3 ) 4 , CoCl(PMe 3 ) 3 and CoMe(PMe 3 ) 4 afforded the same N–H bond activation product [PNP]-Co I (PMe 3 ) 2 ( 3 ). In order to have a better understanding of the mechanism of formation of 3 , in situ IR and 1 H NMR spectroscopic investigations were conducted.The reaction of 1 with Ni(PMe 3 ) 4 afforded the ligand replacement complex 4 while a [PNP]-Ni II Me complex 5 was obtained via deprotonation through the reaction of 1 with NiMe 2 (PMe 3 ) 3 . The molecular structures of 2 – 4 were confirmed by X-ray diffraction analysis.

Description: A new and facile synthesis of O 2 PtF 6 is reported without the demanding synthesis of PtF 6 or the use of high pressure fluorination in the presence of oxygen. The O 2 PtF 6 is obtained in form of single crystals by direct Klemm -type fluorination of commercially available PtO 2 · x H 2 O in a stream of diluted F 2 of atmospheric pressure at a temperature of 275 °C. Its identity and purity was evidenced by powder X-ray diffraction, Raman and infrared spectroscopy. The synthesis allows the preparation of pure dioxygenyl hexafluoridoplatinate(V). The new synthesis of O 2 PtF 6 is deemed more convenient than those that require the extremely reactive PtF 6 .

Description: Four Ln -NDC coordination polymers [ Ln (NDC)(HNDC)(H 2 O)] ( Ln = La ( 1 ), Pr ( 2 ), Nd ( 3 ), Sm ( 4 ), H 2 NDC = 1,4-naphthalenedicarboxylic acid) were hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction. Compounds 1 – 4 are isomorphous, and their structures display a layer constructed from a Ln -organic chain and NDC 2– ligand, in which the H 2 NDC ligands adopt two different acidity-dependent types and coordination modes: HNDC 1– with μ-η 1 :η 1 and NDC 2– with μ-η 1 :η 2 :η 1 :η 2 . The 3D supramolecular networks of 1 – 4 are mainly controlled by hydrogen bonds interactions. The magnetic susceptibilities of complexes 2 – 4 reveal overall antiferromagnetic interactions between the Ln III ions. In addition, thermogravimetric analysis of compound 2 is described.

Description: Since the discovery of symplesite mineral in the late 19th century, a number of structural studies were performed. The crystal symmetry of this mineral was debated to be either monoclinic or triclinic. Even though this debate has ended, agreeing on the triclinic symmetry, no detailed crystal structure was reported so far. In the present contribution, we report on the crystal structure of symplesite. The crystal structure was solved and refined from high-resolution laboratory X-ray powder diffraction data, collected on a natural sample. Symplesite is shown to be isostructural to metavivianite (and possibly to ferrostrunzite).

Description: Hydrothermal reactions of nickel or cobalt nitrate with the dipyridylamide ligand bis(4-pyridylformyl)piperazine (4-bpfp) and either 5-methoxyisophthalate (H 2 omeip) or 5-methylisophthalate (H 2 mip) afforded a series of coordination polymers that were structurally characterized by single-crystal X-ray diffraction. Different synthetic conditions afforded the 1D chain phase {[Ni(Homeip) 2 (H 2 omeip)(bpfp)] · 2H 2 O} n ( 1 ) or the mutually inclined interpenetrated (4, 4) grid system in {[Ni(omeip)(bpfp)(H 2 O)] · 2H 2 O} n ( 2 ). The analogous cobalt phase {[Co(omeip)(bpfp)] · 3H 2 O} n ( 3 ) lacks bound water molecules, which enforces a non-interpenetrated (4, 4) grid structure based on {Co 2 (OCO) 2 } dinuclear clusters. Similar clusters are seen in {[Co(mip)(bpfp)(H 2 O) 2 ] · 3.5H 2 O} n ( 4 ), which manifests a 1D ribbon structural motif. Its nickel congener {[Ni(Hmip) 2 (bpfp)(H 2 O) 2 ] · 2H 2 mip} n ( 5 ) also shows a 1D chain motif. A variable temperature magnetic susceptibility study indicates antiferromagnetic coupling within the dimeric units in 3 and 4 concomitant with single ion effects. Additionally, thermal degradation properties of these new materials are described.

Description: The quaternary thioaluminogermanates Na(AlS 2 )(GeS 2 ) ( 1 ) and K(AlS 2 )(GeS 2 ) ( 2 ) crystallize in the tetragonal space group I 4/ mcm (no. 140) with unit cell parameters a = 7.4274(11) Å, c = 5.8560(12) Å for Na(AlS 2 )(GeS 2 ) and a = 7.8826(2) Å, c = 5.8642(4) Å for K(AlS 2 )(GeS 2 ). The crystal structure comprises of one-dimensional [(AlS 2 )(GeS 2 )] – anionic chains with Al and Ge sharing the tetrahedral site. The alkali metal cations fill the square antiprismatic voids between chains. Both 1 and 2 are semiconductors with bandgap of around 3.6 eV and 3.5 eV, respectively.

Description: The cover picture shows the transformation of a commercially available supported palladium catalyst (Pd/C) into supported particles of the intermetallic compound GaPd 2 . GaPd 2 as well as GaPd can be obtained by controlled solid-gas phase reaction, opening a new path to the synthesis of finely dispersed, small and supported intermetallic materials. The basis for the optimized synthesis is formed by thermodynamic data, i.e. the phase diagram, as well as chemical vapor deposition experiments, by which large crystals of GaPd 2 can be obtained. The supported materials show very promising catalytic properties, e.g. in the semi-hydrogenation of acetylene. Synthesis of supported materials allows to obtain high-performance materials which combine the excellent catalytic selectivity of unsupported bulk intermetallic compounds with high activity, thus easing industrial application.

Description: The complexes [Cu 5 (CN) 5 (5-ph-2,2′-bpy) 3 ] n ( 1 ) and {Cu(SCN)(5-ph-2,2′-bpy)} n ( 2 ) were prepared by reaction of CuCl 2 with different bridging ligands such as cyanide- or thiocyanate under hydrothermal conditions in the presence of 5-phenyl-2,2′-bipyridine (5-ph-2,2′-bpy). The copper ions are bridged by cyanide anions to form 1D ribbon with 26-membered {Cu 10 (CN) 8 } rings in complex 1 , whereas the metal ions are bridged by thiocyanate anions to form a 1D chain in complex 2 .

Description: Three zinc(II) coordination polymers {[Zn(tdpa)(bpe)] · 2H 2 O} n ( 1 ), [Zn(tdpa)(bpp)] n ( 2 ), and [Zn(tdpa)(bpypa)] n ( 3 ) were obtained by solvothermal reactions of Zn(NO 3 ) 2 · 6H 2 O with 3,3′-thiodipropionic acid (H 2 tdpa) and corresponding N-donor ligands, namely, trans -1,2-bis(4-pyridyl)ethylene (bpe), 1,3-bis(4-pyridyl)propane (bpp), and 4,4′-bis(4-pyridyl)diphenylamine (bpypa) respectively. Complexes 1 – 3 were characterized by elemental analysis, IR spectroscopy, as well as powder and single-crystal X-ray diffraction. Compound 1 can be considered as a 3D supramolecular architecture based on 2D undulated (4,4) layers, which are connected through hydrogen bonding interactions. 2 possesses a twofold interpenetrating 2D network, whereas 3 exhibits a 3D supramolecular structure based on 2D (6 5 8) layers through hydrogen-bonding interactions and π ··· π stacking interactions. The photoluminescent properties of 1 – 3 were also investigated.

Description: The cover picture shows the mechanism of photodegradation of methylene blue (MB) using coordination complexes, namely, [Zn(btbp)(3-npa)] n , [Co(btbh)(3-npa)] n and {[Co(btbb)(5-nipa)(H2O)]·H2O} n (btbp = 1,3-bis(thiabendazole)propane, btbh = 1,6-bis(thiabendazole)hexane, btbb = 1,4-bis(thiabendazole)butane, 3-H 2 npa = 3-nitro phthalic acid and 5-H 2 nipa = 5-nitro isophthalic acid). Introducing different scavengers used as probes into the system of photocatalytic degradation of MB suggests that superoxide radicals, direct holes and hydroxyl radicals are active species for the photocatalytic degradation. More details are discussed in the article by Cui et al. on pp. 804ff.

Description: Four coordination polymers, namely, [Zn 2 (TIYM)(2,6-PYDC) 2 ] n · n (CH 3 OH) · 3 n (H 2 O) ( 1 ), [Cu(TIYM)(2,6-PYDC)] n · 3 n (H 2 O) ( 2 ), [Co(TIYM)(2,6-PYDC)] n · n (CH 3 OH) · 3 n (H 2 O) ( 3 ), and [Cd 2 (TIYM)(2,6-PYDC) 2 (H 2 O)] n · n (H 2 O) ( 4 ) with the flexible N-containing ligand [tetrakis(imidazol-1-ylmethyl)methane (TIYM)] and the N-containing dicarboxylic acid [2,6-pyridinedicarboxylic acid (2,6-PYDC)] were prepared. Compounds 1 – 4 show various structures because of different N–C center –N angles ( θ ) of TIYM ligands and changing coordination modes of 2,6-PYDC. Compounds 1 , 2 , and 3 display a similar 1D ladder-like chain, whereas 4 gives a 1D quad-core lifting platform shaped belt. The structural diversities in 1 – 4 suggest that the multiple coordination modes or the different freely twist angles of ligands and the presence of different metal atoms play important roles in the resulting structures of the coordination polymers. Furthermore, the solid-state luminescence properties of 1 and 4 , and the magnetic properties of 3 were investigated.

Description: A material for both magnetic coupling and electrocatalytic hydrogen evolution based on the copper complex, [(L) 2 Cu 2 ] is formed by the reaction of CuCl 2 · 2H 2 O with the tetradentate ligand 6-(3-aminomethylpropanol)-2-tert-buty-4-methylphenol (H 2 L), which is prepared by reaction of 2- tert -butyl-4-methylphenol, 3-amino-1-propanol, and formaldehyde. Structural studies show that in the solid state complex 1 exhibits strong antiferromagnetic exchange interaction between copper(II) ions mediated by oxygen-bridges. In liquid, 1 becomes a monomer, and can electrocatalyze hydrogen generation both from acetic acid with a turnover frequency (TOF) of 101.70 mol of hydrogen per mole of catalyst per hour at an overpotential (OP) of 941.6 mV (in DMF), and a natural buffer with a TOF of 650 mol of hydrogen per mole of catalyst per hour at an OP of 836.7 mV.

Description: The cover picture shows the self-assembly of the ligand H 2 (3-MeOsalamo) (H 2 L) with Ni(OAc) 2 ·4H 2 O, Ce(NO 3 ) 3 ·6H 2 O and terephthalic acid (H 2 bdc) to yield the Ni II –Ce III heterotetranuclear complex, [{Ni(L)Ce(NO 3 ) 2 (CH 3 OH)(DMF)} 2 (bdc)]. Two crystallographically equivalent [Ni(L)Ce(NO 3 ) 2 (CH 3 OH)(DMF)] moieties lie in the inversion center, and are linked by one (bdc) 2– ligand leading to a heterotetranuclear dimer, in which the carboxylato group bridges the Ni II and Ce III atoms. More details can be found in the article by Wen-Kui Dong et al. on page 834ff.

Description: A simple approach was introduced to predict the corrosion inhibition efficiency of some imidazole and benzimidazole derivatives as well as linear organic compounds containing several polar functional groups. In contrast to available predictive methods including quantitative structure-activity relationship models (QSAR models) and quantum methods, there is no need to use complex computer codes and unusual complicated molecular descriptors as well expert users. For 34 nitrogen containing corrosion inhibitors, where the results of two complex models were available, the root mean squared (RMS) deviations of the new method is 4.58, which is much lower than the computed outputs of two available models. The RMS value of the new method is 6.15 for further eleven compounds, which confirm high reliability of the new correlation.

Description: Molecular dynamics simulations unravel the association of citrate to (10–10) and (000–1) growth fronts of zinc oxide and demonstrate an unexpected mobility of the surfactant. Citrate association to perfectly planar (10–10) and (000–1) ZnO-ethanol interfaces was found to be favored over dissociation by 1.5–2 eV hence suggesting strongly bound, immobilized surfactants. However, intramolecular stress prevents binding of all three carboxyl groups to planar surfaces and the typical arrangement is that of two carboxyl-Zn contacts (including two salt bridges each) whilst the remaining carboxyl group is dangling into the solvent. As a consequence, the surfactant exhibits a “walking” mechanism to move along the surface by exchanging the role of its carboxyl groups. This finding has strong implications for the role of citrate during crystal growth as illustrated by a recently developed simulation scheme based on hundreds of individual Zn 2+ and OH – ion association steps. In particular, for the (10–10) surface – which grows via formation of ridges embedded by {10–10} faces – these simulations show how citrate ions move towards steps and bind to the growth front by additional 4 eV per surfactant molecule.

Description: The nitridomagnesogermanate Ca 2 Mg 5 GeN 6 was synthesized at 780 °C using a sodium flux in sealed tantalum ampules. Pure metals were used as starting materials and sodium azide NaN 3 was added as nitrogen source. Ca 2 Mg 5 GeN 6 was obtained as a byproduct in the form of colorless platelet-like crystals. Solution and refinement of the crystal structure [space group P 6 3 / mmc (no. 194), Z = 1, a = 3.453(2), c = 17.506(13) Å and V = 180.8(2) Å 3 ] were performed on the basis of single-crystal X-ray diffraction data. Ca 2 Mg 5 GeN 6 represents the first layered nitridogermanate. Its structure is made up of corner-sharing (Mg/Ge)N 4 tetrahedra and corner-sharing trigonal planar (Mg/Ge)N 3 units with mixed occupancy of Mg and Ge. Ca 2+ ions are located in between the sheets. The crystal structure is closely related to that of the nitridomagnesoaluminate CaMg 2 AlN 3 as well as to the carbides ScAl 3 C 3 and UAl 3 C 3 .

Description: New oxygen-rich compounds starting from the amino acids β-alanine and L -aspartic acid were synthesized and comprehensively analyzed including multinuclear NMR spectroscopy and vibrational spectroscopy. Thermal stabilities were measured and the behavior towards external stimuli like friction or impact were determined. Detonation and combustion parameters were predicted by using the EXPLO5 V6.02 code and were compared with common explosives. In addition, crystal structures were obtained for two compounds.

Description: Oxidation of N , N -bis(diphenylphosphanyl)naphthalen-1-amine ( 1 ) with elemental sulfur or gray selenium (1:1 molar ratio) gave the corresponding monosulfide and monoselenide bis(phosphanyl)amine ligands C 10 H 7 -1-N(P( E )Ph 2 )(PPh 2 ) [ E = S ( 2 ), Se ( 3 )], respectively. Reactions of 2 and 3 with M Cl 2 (cod) ( M = Pd, Pt) afforded [ M Cl 2 { 2 -κ 2 P,S }] [ M = Pd( 4 ), Pt( 5 )] and [ M Cl 2 { 3 -κ 2 P,Se }] [ M = Pd( 6 ), Pt( 7 )], respectively. In contrast, reactions of the same ligands with NiCl 2 (PPh 3 ) 2 resulted in deselenization and desulfurization, producing complex 8 with the formula [NiCl 2 {1-κ 2 P,P }]. Ligands 2 and 3 , as well as their complexes 4 – 7 and 8 were identified and characterized by multinuclear NMR ( 1 H, 13 C, 31 P, and 77 Se NMR) spectroscopy, elemental analysis, and IR spectroscopy. Additionally, the molecular structure of 8 was obtained.

Description: Polycrystalline samples of the isotypic quaternary compounds RE Ni 2 Ga 3 In ( RE = Y, Gd – Tm) were obtained by arc-melting of the elements. Crystals of the gadolinium compound were found by slow cooling of an arc-melted button of the initial composition “GdNiGa 3 In”. All samples were characterized by powder X-ray diffraction. The structure of GdNi 2 Ga 2.89 In 1.11 was refined from single-crystal X-ray diffractometer data: new type, Pnma , a = 2426.38(7), b = 418.17(2), c = 927.27(3) pm, wR 2 = 0.0430, 1610 F 2 values and 88 variables. Two of the six crystallographically independent gallium sites show a small degree of Ga/In mixing. The nickel atoms show tricapped trigonal prismatic coordination by gadolinium, gallium, and indium. Together, the nickel, gallium, and indium atoms build up a complex three-dimensional [Ni 2 Ga 3 In] δ – network, which leaves cages for the gadolinium atoms. The indium atoms form zigzag chains with In–In distances of 337 pm. The crystal chemical similarities of the polyhedral packing in the GdNi 2 Ga 3 In and La 4 Pd 10 In 21 structures are discussed.

Description: Neutral ferrocene-based burning rate (BR) catalysts show strong migration trends and volatility during long-time storage and curing of the composite solid propellants. To reduce these disadvantages thirty-two ferrocenyl quaternary ammonium compounds, paired with polycyano anions, were synthesized and characterized by 1 H NMR, 13 C NMR, and UV/Vis spectroscopy, as well as elemental analysis. Additionally, crystal structures of eight compounds were confirmed by single-crystal X-ray diffraction. TG and DSC analyses indicated that the compounds containing 1,1,2,3,3-pentacyanopropenide anions show high thermal stability. Cyclic voltammetry studies suggested that they are quasi-reversible or irreversible redox systems. Anti-migration tests verified that the tested compounds show very low migration tendency and some of them exhibit no migration after 30 days aging at 70 °C. Their catalytic efficiency in the thermal decomposition of ammonium perchlorate (AP), 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), and 1,2,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) were examined by DSC analyses. The results revealed that most of the compounds exhibit distinct effects on the thermal degradation of AP and RDX. Two compounds have good catalytic ability in the thermal decomposition of HMX, representing rare examples of the reported ferrocenyl ionic compounds, which display catalytic property during combustion of HMX.

Description: Herein, a new and efficient approach towards the oxidative cross-coupling of benzylalcohol and various aromatic amines to form corresponding imines with high degree conversion (〉80 %) and chemo-selectivity using lanthanide salts as pre-catalysts is presented. The catalyzed oxidative cross-coupling reaction using La(NO 3 ) 3 · 6H 2 O as pre-catalyst displayed a broad substrate scope. The reaction afforded various substituted imines from the reaction of benzylalcohol with ample variety of amines in good yields.

Description: By self-assembly of a Salamo-type ligand H 2 L [H 2 L = 1,2-bis(3-methoxysalicylideneaminooxy)ethane] with Ni(OAc) 2 · 4H 2 O, Ce(NO 3 ) 3 · 6H 2 O, and H 2 bdc (H 2 bdc = terephthalic acid), a novel Ni II -Ce III heterometallic complex, [{Ni(L)Ce(NO 3 ) 2 (CH 3 OH)(DMF)} 2 (bdc)], was obtained. Two crystallographically equivalent [Ni(L)Ce(NO 3 ) 2 (CH 3 OH)(DMF)] moieties lie in the inversion center, and are linked by one bdc 2– ligand leading to a heterotetranuclear dimer, in which the carboxylato group bridges the Ni II and Ce III atoms. Moreover, the photophysical properties of the Ni II -Ce III complex were studied.

Description: The ternary niobium compound AlNbBr 8 ( 1 ) was synthesized by degradation of NbS 2 Br 2 in AlBr 3 and from elements. Crystal structure and thermodynamic properties of sublimation process were studied.

Description: The synthesis of ammine metal azides is achieved through a simple route in liquid ammonia solution. Azides of silver, sodium, manganese, and zinc were obtained as ammine complexes from liquid ammonia and the solid compounds were characterized. The NH 3 solutions were investigated by means of NMR spectroscopy as well. The triamminesilver(I) azide as well as the unusual tetraamminesilver(I) and pentaamminesodium(I) azides are presented. The structures of the hexaamminemanganese(II) and hexaamminezinc(II) azides, which crystallize with four ammonia molecules of solvation, are elucidated. From these compounds the binary azides Mn(N 3 ) 2 and Zn(N 3 ) 2 were obtained by (careful) heating.

Description: Three coordination complexes, namely, [Zn(btbp)(3-npa)] n ( 1 ), [Co(btbh)(3-npa)] n ( 2 ), and {[Co(btbb)(5-nipa)(H 2 O)] · H 2 O} n ( 3 ) (btbp = 1,3-bis(thiabendazole)propane, btbh = 1,6-bis(thiabendazole)hexane, btbb = 1,4-bis(thiabendazole)butane, 3-H 2 npa = 3-nitrophthalic acid and 5-H 2 nipa = 5-nitroisophthalic acid) were synthesized under hydrothermal conditions and characterized by physicochemical and spectroscopic methods as well as by single-crystal X-ray diffraction. Complex 1 features a fascinating meso -helical chain, which is further extended into a 2D supramolecular framework involving π ··· π stacking interactions. Complexes 2 and 3 show dinuclear structures. Complex 2 is further connected through C–H ··· O hydrogen bonding interactions to afford a 2D supramolecular layer, whereas complex 3 is further extended to a rare 2-nodal (3,4)-connected supramolecular sheet with a point symbol of {3.4 2 .5.6.7} 2 {3.8 2 } by O–H ··· O hydrogen bonding interactions. The electrochemical behaviors of the two cobalt complexes 2 and 3 were reported. Moreover, the luminescent properties for 1 and the photocatalytic properties for the complexes were investigated.

Description: Cobalt coordination complexes containing a substituted isophthalate ligand and hydrogen-bonding capable dipyridylamide ligands were prepared hydrothermally and structurally characterized by single-crystal X-ray diffraction. {[Co(nip)(3-pina)] n ( 1 ) (nip = 5-nitroisophthalate, 3-pina = 3-pyridylisonicotinamide) displays [Co(nip)] n 1D ribbon motifs with embedded {Co 2 (OCO) 2 } dimeric units, linked by L-shaped 3-pina tethers into a 3D [Co(nip)(3-pina)] n coordination polymer network with pcu topology. In contrast, {[Co(nip)(4-pmina)(H 2 O)] · H 2 O} n ( 2 ) (4-pmina = 4-pyridylmethylisonicotinamide) manifests a twofold interpenetrated 6 6 topology diamondoid network. {[Co(meoip)(3-pina)] n ( 3 ) (meoip = 5-methoxyisophthalate) has a dimer-based 3D pcu network as seen in 1 . [Co(meoipH) 2 (4-pmina) 2 (H 2 O) 2 ] ( 4 ) contains neutral coordination complexes linked by hydrogen-bonding into supramolecular ribbons. Thermal properties of these new solids were also investigated.

Description: To further explore the coordination possibilities of the flexible tripodal ligand, 4,4′,4′′-(benzene-1,3,5-triyl-tris(oxy))tribenzoic acid (H 3 BTTB), two solvent-controlled three-dimensional (3D) manganese(II) coordination polymers, [Mn 3 (BTTB) 2 (H 2 O) 4 ](H 2 O) 2 ( 1 ) and [Mn 3 (BTTB) 2 (DMF) 2 ](DMF) 2 ( 2 ), were synthesized and characterized. Single crystal X-ray diffraction analysis indicates that in the Mn II complexes the BTTB ligands exhibit two coordination modes, which have not been reported previously. Complexes 1 and 2 involve different one-dimensional (1D) rod-shaped metal–carboxylate secondary building units (SBUs). The 1D SBUs are further extended to afford two different three-dimensional (3D) frameworks with similar flu topology via linkage of the BTTB ligands. The results demonstrate that the reaction solvent as well as conformation and coordination mode of BTTB ligands play key roles on the formation of the final framework structures. Additionally, their luminescent properties were investigated.

Description: The increasing number of metalloid clusters, synthesized in the last couple of years, gives new insights into the formation process of metals or semi-metals. Metalloid clusters of the transition metals, especially the coinage metals are thereby of particular interest and the number of structurally characterized metalloid gold clusters has increased over the last decade. Most of these clusters are stabilized via aryl thiolate ligands. Herein, the synthesis and crystal structures of the lithium and potassium salts of the bulky SSi(SiMe 3 ) 3 ligand are presented together with the synthesis of suitable M I precursors ( M = Cu, Ag, Au) for further build-up reactions to metalloid clusters.

Description: Three complexes with the ditopic ligand 4′-[4-(quinolin-8-yloxymethyl)phenyl]-2,2′:6′,2′′-terpyridine (abbreviated as L ), [Ni(L) 2 ](CH 3 COO) 2 ( 1 ), [Cd(L) 2 ](ClO 4 ) 2 ( 2 ), and [Cu 2 (L) 2 ](ClO 4 ) 4 · 4DMF ( 3 ), were synthesized and characterized by elemental analysis, IR spectroscopy, and structurally analyzed by X-ray single-crystal diffraction. Interestingly, in complexes 1 and 2 , two ligands adopt a tridentate chelating pattern where the oxaquinoline group is non-coordinated and coordinate with one M II ion ( M = Ni for 1 , M = Cd for 2 ) to form a mononuclear unit. In complex 3 , two ligands bridge two Cu II ions by pyridyl N atoms, ethereal O atoms, and quinolyl N atoms in a head-to-tail mode to generate a dinuclear [Cu 2 L 2 ] unit. Moreover, extended 1D and 2D supramolecular architectures are further constructed in 1 – 3 by multiple secondary interactions such as aromatic stacking and hydrogen bonding. Notably, the structural diversity of complexes 1 – 3 can be properly assigned to the central metal ions that have distinct coordination preferences. In addition, luminescent properties of the ligand and complex 2 were also investigated.

Description: The synthesis and structural characterization of trans -[IrCl(NO)(P t Bu 2 H) 2 ]BF 4 ( 1 ) is reported. The title compound was prepared in good yield in the reaction of in situ-prepared trans -[IrCl(coe)(P t Bu 2 H) 2 ] (coe = cis -cyclooctene) with an appropriate amount of nitrosonium tetrafluoridoborate in dichloromethane at room temperature. Single crystals of 1 were grown from dichloromethane/diethyl ether and were analyzed by X-ray crystallography.

Description: Mechanochemical preparation and characterization of surface-functionalized magnetic boron nanoparticles for biomedical applications are presented. Alloying with the stainless steel ball milling material during mechanochemical activation proved to be an alternative route to introduce magnetic properties to the nanomaterials, while functionalization with biomolecules provided biocompatible surfaces for bioconjugation.

Description: As a key research objective for environmentally friendly energetic materials, energetic salts without heavy metal have received wide attention. The energetic salts DAG · PA · H 2 O ( 1 ) and DAG · TNR · H 2 O ( 2 ) were synthesized by using diamino-glyoxine (DAG) and picric acid (PA) or 2, 4,6-trinitro-resorcinol (TNR) as raw materials, and their structures were characterized by elemental analysis, FT-IR, 1 H NMR, and 13 C NMR spectroscopy. Single crystals of the title salts were cultured and their structures were determined by X-ray single-crystal diffraction. Both salts belong to the triclinic space group P 1 with density values of 1.764 and 1.751 g · cm –3 , respectively. The thermal decomposition behaviors of both salts were investigated by differential scanning calorimetry (DSC), the non-isothermal kinetic parameters and the critical temperature of thermal explosion were calculated. The heats of formation for the salts were also determined through the combustion heats date measured by using the oxygen bomb calorimetry. In addition, the detonation pressure ( P ) and detonation velocities ( D ) of the salts were predicted by using the K-J equations, and their sensitivities towards impact and friction were tested. The results indicated that the title salts have potential applications in the field of energetic materials.

Description: Reactions of bis(phosphinimino)methanes H 2 C(PPh 2 N R ) 2 [ R = SiMe 3 (L 1 H), Ph (L 2 H), 2,6- i Pr 2 -C 6 H 3 (DIPP) (L 3 H)] with Zn R 2 ( R = Me, Et) yielded the corresponding bis(phosphinimino)methanide zinc complexes LZnMe [L 2 ( 1 ), L 3 ( 2 )] and LZnEt [L 1 ( 3 ), L 2 ( 4 ), and L 3 ( 5 )]. Complexes 1 – 5 were characterized by heteronuclear NMR ( 1 H, 13 C, 31 P) and IR spectroscopy, elemental analysis, and single-crystal X-ray diffraction.

Description: Three diorganocobalt chlorides [CoClMe(PMe 3 ) 2 –{(C 5 H 6 )–CH=O}] ( 4 ), [CoClMe(PMe 3 ) 2 –{(C 6 H 8 )–CH=O}] ( 5 ), and [CoClMe(PMe 3 ) 2 –{(C 6 H 7 Me meta )–CH=O}] ( 6 ) were synthesized through cyclometalation reactions with aldehyde as an anchoring group involving aliphatic vinylic C–Cl bond activation. Complexes 4 – 6 were characterized by IR and NMR spectroscopy. The crystal and molecular structures of complexes 4 and 5 were determined by single-crystal X-ray diffraction. Complexes 4 – 6 are stable in solution at room temperature, but they decompose at above 30 °C affording C,C-couplings products with the formation of [Co(PMe 3 ) 3 Cl]. The results of this work will be important for people to deepen the understanding of the C–Cl bond activation mechanism.

Description: The reactions of As 2 O 3 , SbCl 3 , and (BiO) 2 CO 3 with oleum (65 % SO 3 ) yielded single crystals of As(S 2 O 7 )(HS 2 O 7 ) [monoclinic, P 2 1 / c , Z = 4, a = 16.549(1), b = 6.6743(5), c = 9.9498(6) Å, β = 102.672(8)°, V = 1072.672(8) Å 3 ], Sb 2 (SO 4 ) 2 (S 2 O 7 ) [monoclinic, P 2 1 / n , Z = 4, a = 9.1586(2), b = 6.9981(2), c = 17.7956(4) Å, β = 100.9690(8)°, V = 1119.73(5) Å 3 ], and Bi 2 (S 2 O 7 ) 3 [triclinic, P , Z = 2, a = 6.5734(1), b = 10.1954(2), c = 11.5121(2) Å, α = 90.996(1)°, β = 96.976(1)°, γ = 94.870(1)°, V = 762.75(2) Å 3 ]. As(S 2 O 7 )(HS 2 O 7 ) shows the arsenic atoms in a trigonal pyramidal coordination of the oxygen atoms of one chelating S 2 O 7 2– and one monodentate HS 2 O 7 – group. The distinct As(S 2 O 7 )(HS 2 O 7 ) molecules are connected with each other by hydrogen bonds to form layers. Sb 2 (SO 4 ) 2 (S 2 O 7 ) shows the Sb 3+ cations in a seesaw-type coordination of oxygen atoms from both anions. In Bi 2 (S 2 O 7 ) 3 the Bi 3+ cations are in a square prismatic oxygen coordination of disulfate units. The antimony and the bismuth compounds exhibit complex three-dimensionally linked structures. The syntheses and the crystal structures, as well as the thermal decomposition of Sb 2 (SO 4 ) 2 (S 2 O 7 ) are presented.

Description: Silver acetate AgOAc reacts with dry liquid ammonia under the formation of colorless needle-shaped crystals of diammine silver(I) acetate [Ag(NH 3 ) 2 ]OAc ( 1 ). The compound crystallizes in the monoclinic space group P 2 1 / c with a = 8.0205(2), b = 12.4161(3), c = 6.0938(2) Å, β = 107.741(4)°, and V = 577.98(3) Å 3 at 123 K with Z = 4. The crystal structure shows the presence of almost linear [Ag(NH 3 ) 2 ] + cations, which are arranged in a corrugated chain of equidistant silver atoms. The Ag–Ag distance is 3.1089(11) Å, which falls in the range of “argentophilic” interactions. After warming to room temperature and removal of the solvent, compound 1 was found unchanged as evidenced by powder X-ray diffraction, thermogravimetric and mass-spectrometric analysis, as well as IR and Raman spectroscopy.

Description: A series of chalcogenidoantimonates, namely [Zn(NH 3 ) 6 ](Sb III 4 S 7 ) ( 1 ), [Zn(NH 3 ) 6 ]{Zn(NH 3 ) 3 Sb V S 4 } 2 · NH 3 ( 2 ), [Mn(NH 3 ) 6 ](Sb III Se 2 ) 2 ( 3 ) and [Zn(NH 3 ) 4 ]{Zn(NH 3 )Sb III Se 3 } 2 · 3NH 3 ( 4 ) are synthesized by solvothermal technique in liquid ammonia at 50 °C from elemental zinc or manganese, antimony and sulfur or selenium. 1 (space group P ) and 2 ( P ) crystallize centrosymmetrically, whereas 3 ( Pna 2 1 ) and 4 ( P 2 1 ) represent polar structures. All compounds contain discrete cationic [Zn(NH 3 ) 4 ] 2+ , [Zn(NH 3 ) 6 ] 2+ , and [Mn(NH 3 ) 6 ] 2+ ammine complexes. In the anionic structure parts, corner-connected trigonal-pyramidal SbS 3 and SbSe 3 are the characteristic building units. 1 and 4 contain 2D polymeric anions, in the latter case with Zn 2+ cations incorporated in a selenidoantimonate(III) network. The polymeric anion in the structure of 3 is a helical chain. 2 is a molecular compound and contains dinuclear anions [S 3 Sb–S–Zn(NH 3 ) 3 ] 2– with Sb V . Raman measurements show the Sb–Ch valence vibrations in the expected region between 250–370 cm –1 for 1 and at 212 cm –1 for 4 . According to the reflectance spectrum 4 is a semiconductor with an optical band gap of 2.05(5) eV.

Description: . Sr 2 CoOsO 6 , a new osmium based ordered semiconductor double perovskite was prepared by solid state synthesis from the respective binary oxides. Room temperature PXRD analysis shows the compound to be tetragonal [ I 4/ m ; a = 5.5503(1) Å and c = 7.9320(1) Å], whereas low temperature synchrotron data refinement has revealed a second monoclinic polymorph [ I 2/ m ; a = 5.4969(2) Å, b = 5.4979(2) Å, c = 8.0090(1) Å and γ = 90.527(1)°] with a fully ordered rocksalt arrangement of cobalt and osmium atoms over the perovskite B -sites. Heat capacity and magnetic measurements indicate that Sr 2 CoOsO 6 shows antiferromagnetic ordering below T N = 108 K followed by a second magnetic transition at T 2 = 65 K. It was shown that the change from the tetragonal to the monoclinic phase occurs at T N .

Description: . The ternary germanides RE Rh 6 Ge 4 ( RE = Y, La, Pr, Nd, Sm–Lu) were obtained by arc-melting of the elements and subsequent annealing. Single crystals were grown from bismuth fluxes. The samples were studied by X-ray diffraction on powders. The structures of five members were refined from single crystal diffraction data: LiCo 6 P 4 type, P m 2, a = 715.8(1), c = 387.33(8) pm, wR = 0.0238, 332 F 2 values for LaRh 6 Ge 4 , a = 715.0(1), c = 384.96(7) pm, wR = 0.0211, 329 F 2 values for PrRh 6 Ge 4 , a = 714.28(9), c = 382.57(6) pm, wR = 0.0136, 327 F 2 values for SmRh 6 Ge 4 , a = 714.2(1), c = 381.6(1), wR = 0.0270, 327 F 2 values for GdRh 6 Ge 4 , and a = 714.2(2), c = 379.0(1) pm, wR = 0.0273, 324 F 2 values for HoRh 6 Ge 4 with 19 variables per refinement. The RE Rh 6 Ge 4 structures have two crystallographically independent germanium sites in trigonal prismatic coordination, manifesting the close structural relationship with metal-rich phosphides. Together, the rhodium and germanium atoms build up three-dimensional [Rh 6 Ge 4 ] networks, which leave large channels for the rare earth atoms. Each rare earth atom has coordination number 20 with 12 Rh, 6 Ge, and 2 RE neighbors. Temperature dependent magnetic susceptibility measurements indicate Pauli paramagnetic behavior for YRh 6 Ge 4 , LaRh 6 Ge 4 , and LuRh 6 Ge 4 . The compounds RE Rh 6 Ge 4 ( RE = Gd–Yb) are Curie-Weiss paramagnets. Antiferromagnetic ordering was observed at 8.4(5) K (GdRh 6 Ge 4 ), 13.6(5) K (TbRh 6 Ge 4 ), 5.1(5) K (DyRh 6 Ge 4 ), and 8.9(5) K (YbRh 6 Ge 4 ). DyRh 6 Ge 4 and YbRh 6 Ge 4 show metamagnetic transitions at 2.5(5) and 45(2) kOe, respectively.

Description: Reaction of manganese(II) thiocyanate with 2-chloropyrazine leads always to the formation of a compound of composition Mn(NCS) 2 (2-chloropyrazine) 4 ( 1 - Mn/Cl ) that consists of discrete complexes, in which the manganese cation is coordinated by two terminal thiocyanato anions and four 2-chloropyrazine ligands. In contrast, with 2-methylpyrazine only an aqua complex of composition Mn(NCS) 2 (2-methylpyrazine) 2 (H 2 O) 2 ( 1 - Mn/CH 3 ) is obtained that also consists of discrete octahedrally coordinated complexes. Moreover, a few single crystals of Mn(NCS) 2 (2-chloropyrazine) 4 · Mn(NCS) 2 (2-chloropyrazine) 2 (H 2 O) 2 · 2-chloropyrazine trisolvate ( 2 - Mn/Cl ) and Mn(NCS) 2 (2-methylpyrazine) 2 (H 2 O) 2 · Mn(NCS) 2 (H 2 O) 4 ( 2 - Mn/CH 3 ) were accidently obtained but no larger amounts are available. On heating, 1 - Mn/Cl and 1 - Mn/CH 3 transforms into new compounds of composition Mn(NCS) 2 (L) 2 (L = 2-chloropyrazine) ( 4 - Mn/Cl ) and 2-methylpyrazine ( 3 - Mn/CH 3 ). Surprisingly on further heating 1 - Mn/CH 3 looses additional 2-methylpyrazine ligands and transforms into a new compound of composition Mn(NCS) 2 (2-methylpyrazine) ( 4 - Mn/CH 3 ). Compound 4 - Mn/Cl is isotypic to its cobalt(II) analog and 4 - Mn/CH 3 is isotypic to Cd(NCS) 2 (2-methylpyrazine) reported recently and therefore, both structures were refined by the Rietveld method. The crystal structures of both compounds are strongly related. They consists of dimeric units, in which each two manganese cations are linked by pairs of μ-1,3-bridging thiocyanato anions, which are further connected into layers by single μ-1, 3-bridging anionic ligands. In contrast to 4 - Mn/Cl , in 4 - Mn/CH 3 these layers are further linked into a 3D coordination network by the 2-methylpyrazine ligands. Magnetic measurements reveal that 1 - Mn/Cl , 1 - Mn/CH 3 , and 3 - Mn/CH 3 shows only Curie- or Curie-Weiss paramagnetism, whereas 4 - Mn/Cl and 4 - Mn/CH 3 shows antiferromagnetic ordering at T N = 22.9 K and at 26.5 K. The results of these investigations are compared with those obtained for related compounds.

Description: . Black platelets of Bi 39.67(7) Ru 2 Br 35.0(2) were crystallized from a melt of Bi, BiBr 3 , and Ru. In the tetragonal crystal structure [ P 4/ mbm , a = 1311.92(6) pm, c = 3018.2(4) pm at 155(5) K], cluster cations [(Bi 8 2+ )Ru 2+ (Bi 8 2+ )] are embedded in a matrix of disordered bromido-bismuthate(III) groups. A thorough analysis of the disorder in the anionic part enabled the unambiguous assignment of the cluster charge. The η 4 -coordination of the two Bi 8 2+ square antiprisms to the Ru II atom in the sandwich complex resembles the bonding of Bi 5 + and Bi 8 2+ in the clusters [(Bi 5 + )Ru + (Bi 4 Br 4 )Ru + (Bi 5 + )] and [(Bi 8 2+ )Ru + (Bi 4 Br 4 )Ru + (Bi 5 + )] as well as of Bi 4 2– in 1 ∞ [(Bi 4 2– )Ru + (Bi 4 Br 4 )Ru + ]. By combining crystal chemical considerations for all mentioned compounds and using quantum chemical calculations, a common bonding scheme for the coordination compounds of bismuth polycations and polyanions was established. The η 4 -coordinating bismuth polycations and polyanions act as six electron donors, comparable to nido -carborane ligands, Zintl anions E 9 4– and E 5 6– ( E = Si to Pb), cyclopentadienyl ligands, or the cyclobutadiene dianion. The electron count for the transition metal is 18 in all finite clusters.

Description: . Previous attempts to synthesize and isolate (thiobisphenolate) vanadium(V) dioxido complexes had always provided their dimers containing [O=V(μ-O) 2 V=O] 2+ cores, and these also dominate the solution reactivity. Hence, the behavior of their parent monomers, which represent the major species in solution, has remained uncertain. Herein we report the development of a synthetic route that allowed for the successful isolation, spectroscopic investigation, and structural characterization of the monomer PPh 4 [ S LVO 2 ] ( 3 ) [ S L 2– = 2′2-thiobis(2, 4-di- tert -butylphenolate)]. For this purpose PPh 4 [ S LVOCl 2 ] ( 1 ) had to be accessed first in order to convert it to the ethoxido compound PPh 4 [ S LVO(OEt) 2 ] ( 2 ), which is more prone to hydrolysis. Treatment of 2 with stoichiometric amounts of water followed by immediate cooling to –30 °C led to crystals of 3 . After its dissolution NMR spectra were recorded that were identical with those obtained after dissolution of its dimer, thus confirming the monomer/dimer equilibrium postulated previously. The molecular structure of 3 revealed the absence of a V ··· S interaction, which, however, stabilizes its dimer, and thus suggested the employment of a bisphenolate ligand lacking a bridging sulfur atom to obtain an analogue, which does not undergo dimerization in solution. In Et L 2– the sulfur atom is replaced by an ethylmethine unit and indeed the corresponding complex NBu 4 [ Et LVO 2 ] ( 4 ) proved to be stable as a monomer. Investigation of its potential as a catalyst for the oxidative dehydrogenation of 9-fluorenol confirmed a much lower reactivity in comparison to dimeric complexes, which is discussed.

Description: Two complexes, cis -[MnL 2 (NCS) 2 ] ( 1 ) and cis -[ZnL 2 (NCS) 2 ] ( 2 ) with asymmetrical substituted triazole ligands [L = 3, 4-dimethyl-5-(2-pyridyl)-1, 2, 4-triazole], were synthesized and characterized by elemental analysis, UV/Vis and FT-IR spectroscopy as well as thermogravimetric analyses (TGA), powder XRD, and single-crystal X-ray diffraction. In the complexes, each L molecule adopts a chelating bidentate mode by the nitrogen atoms of pyridyl and triazole. Both complexes have a similar distorted octahedral [ M N 6 ] core ( M = Mn 2+ and Zn 2+ ) with two NCS – ions in the cis position.

Description: . The multi-shaped amorphous alloy (Ni-B) powders were prepared by complexing reduction route using sodium borohydride (NaBH 4 ) as reductant with assistance of ultrasonic wave. The selected complexants, i.e. water, ammonia, salicylic acid, and ethylene diamine tetraacetic acid (EDTA) possess sequentially escalating complexation ability. The chemical composition and shapes of the product samples obtained under different conditions were characterized by X-ray powder differaction, selected area electron diffraction, and transmission electron microscope. The influence of reaction conditions such as the types of Ni-B, temperatures, NaBH 4 concentrations, and sodium hydroxide (NaOH) content on the hydrogen generation rate of hydrolysis of NaBH 4 solution were investigated in detail. The results show that the as-prepared Ni-B powders all belong to amorphous alloy with variable element contents, and the Ni-B sample prepared from EDTA complexation, possessing the best fineness and dispersity, has the strongest catalytic activity. The mean apparent activation energy of the hydrolysis reaction is 64.90 kJ · mol –1 . The NaBH 4 concentration has little impact on hydrogen generation rate, implying that the catalytic hydrolysis of NaBH 4 solution should be the pseudo zero-order reaction. Keeping the NaOH content at below 5 % could inhibit the hydrolysis of NaBH 4 solution, but the NaOH contents from 10 % to 15 % will significantly promote the hydrolysis rate of NaBH 4 . The hydrolysis reaction mechanisms, especially the effect of NaOH content on the hydrolysis reaction were also analyzed.

Description: The intermetallic compounds Sr 2 Au 6.52 Zn 2.48 , Sr 2 Au 6 Zn 3 , and Sr 2 Au 6 Ga 3 were obtained by induction melting of the elements in sealed tantalum tubes. Their structures were studied by X-ray diffraction on powders and refined from single crystal diffraction data: R c , a = 844.5(2), c = 2187.7(5) pm, wR 2 = 0.0411, 936 F 2 values and 20 variables for Sr 2 Au 6.52 Zn 2.48 ; a = 841.6(2), c = 2191.5(7) pm, wR 2 = 0.0126, 587 F 2 values and 19 variables for Sr 2 Au 6 Zn 3 ; and a = 841.9(2), c = 2191.1(7) pm, wR 2 = 0.0199, 660 F 2 values and 19 variables for Sr 2 Au 6 Ga 3 . The gold substructures of Sr 2 Au 6 Zn 3 and Sr 2 Au 6 Ga 3 can be considered as diamond polytypes with 6R stacking sequences (287–304 pm Au–Au in Sr 2 Au 6 Zn 3 ). The cavities formed by this network are filled in an ordered manner by strontium atoms and Zn 3 (281 pm Zn–Zn), respectively Ga 3 (286 pm Ga–Ga) triangles in a 2:1 ratio. Consequently one can describe the Sr 2 Au 6 Zn 3 and Sr 2 Au 6 Ga 3 structures as ordered substitution variants of the Zintl phase CaIn 2 . This structural relationship is discussed on the basis of a group-subgroup Scheme. Sr 2 Au 6.52 Zn 2.48 shows Zn/Au mixing on the triangle.

Description: The templated borate, [C 9 H 14 N] · [B 5 O 6 (OH) 4 ], was synthesized under hydrothermal conditions. Single crystal X-ray diffraction techonology reveals that it crystallizes in the triclinic system, space group P (No. 2). The material was also characterized by element analysis, Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), thermogravimetric and differential thermal analysis (TG-DTA), and luminescence spectroscopy. The compound consisted of isolated pentaborate [B 5 O 6 (OH) 4 ] – and N -butylpyridinium cations [C 9 H 14 N] + . The [B 5 O 6 (OH) 4 ] – anions are connected together by hydrogen bonds to form a three-dimensional framework, in which [C 9 H 14 N] + cations are located in. [C 9 H 14 N] · [B 5 O 6 (OH) 4 ] exhibits tunable luminescence emission at 415–458 nm by means of heating treatment from 100 to 300 °C.

Description: Two alkylimido derivatives of hexamolybdate, (Bu 4 N) 2 [Mo 6 O 18 (≡N- o -COOCH 3 C 6 H 4 )] ( 1 ) and (Bu 4 N) 2 [Mo 6 O 18 (≡N- o -COOCH 2 CH 3 C 6 H 4 )] ( 2 ), were synthesized in high purity and good yields by the reaction of [(C 4 H 9 ) 4 N] 4 [α-Mo 8 O 26 ] and methyl anthranilate or ethyl- o -aminobenzoate hydrochloride with N , N ′-dicyclohexylcarbodiimide (DCC) as a dehydrating agent in dry acetonitrile solution, which were characterized by elemental analyses, IR, UV/Vis, and 1 H NMR spectroscopy as well as ESI-MS, and single-crystal X-ray diffraction study. Compound 1 crystallizes in the monoclinic space group P 2 1 / n with one-dimensional chain structure via intramolecular hydrogen bond. Compound 2 also crystallizes in the monoclinic space group P 2 1 / n with dimer structure by intramolecular hydrogen bonds and π–π interactions between the pairs of cluster anions.

Description: The cover picture shows the frontispieces of all articles published in this Special Issue with research reports from DFG priority program 1178 “Experimental Electron Density as Key to Understanding Chemical Interactions”, highlighting the diverse range of chemistry that is covered herein. Biological processes that determine the effects of drugs consist on a certain interaction between agent and receptor. This molecular recognition is influenced by the electron density distribution. Analysis of these processes enables the rational synthesis of drugs. Electron density measurements are moreover significant for the design of advanced materials with specific features, e.g. the development of new pigments. Thus, color, stability, and durability can be tuned by modifying the electron density. Selected substance classes used in chemical synthesis, drug design and material science were analyzed and their binding and recognition processes were studied and quantified by means of electron density measurements.

Description: . Reactions of the coordinatively unsaturated complexes [Fe 2 (μ-P R 2 )(μ-P R ′ 2 )(CO) 5 ] [ R = R ′ = t Bu ( 1 ); R = t Bu, R ′ = Cy ( 2 )] with nitric oxide in toluene at elevated temperatures were investigated. Thus, the new complexes [Fe 2 (μ-P t Bu 2 ) 2 (NO) 4 ] ( 3 ) and [Fe 2 (μ-P t Bu 2 )(μ-PCy 2 )(NO) 4 ] ( 4 ) were obtained in good yields. The molecular structure of 3 was confirmed by X-ray diffraction study. Compound 4 was also prepared from the coordinatively saturated species [Fe 2 (μ-P t Bu 2 )(μ-PCy 2 )(CO) 6 ] ( 2a ) with nitric oxide in refluxing toluene. Further closely related reactions at 60 °C with the complex 1 and [FeRu(μ-P t Bu 2 ) 2 (CO) 5 ] ( 5 ), respectively, were investigated using preliminary crystal structure determination results.

Description: Two new materials of the composition ({CH 3 (CH 2 ) 15 (CH 3 ) 2 S} + ) 2 [CoBr 4 ] 2– ( 1 ) and ({CH 3 (CH 2 ) 15 (CH 3 ) 2 S} + ) 2 [CuBr 4 ] 2– ( 2 and 3 ), of which the latter exists in two polymorphs, were synthesized. The materials display the synthetically targeted structures, comprising of layers of complex metal ions and layers of long-chain sulfonium cations. The crystal structures of the materials were determined. The interlayer distances are around 24 Å, with metal–metal distances about 8 Å. The magnetic properties of 1 were investigated, and the material is paramagnetic. ({CH 3 (CH 2 ) 15 (CH 3 ) 2 S} + ) 2 [CuBr 4 ] 2 is polymorphic. Both polymorphs crystallize with triclinic symmetry.

Description: Single crystals of Rb 2 H 2 P 2 O 6 · 2H 2 O could be obtained from aqueous solutions of hypodiphosphoric acid and rubidium carbonate. Its crystal structure was determined by X-ray diffraction and it crystallizes in the monoclinic space group P 2 1 / c with Z = 4. The salt-like title compound consists of [H 2 P 2 O 6 ] 2– units in staggered P 2 O 6 -skeleton conformation, Rb + cations, and H 2 O molecules, held together by intermolecular hydrogen bonds of the type O ··· O. The vibrational spectra (IR/FIR and Raman) of the rubidium salt were recorded and an assignment of the vibrational modes is proposed based on the point group C 2 h for the P 2 O 6 -skeleton of the anion. The thermal behavior of Rb 2 H 2 P 2 O 6 · 2H 2 O is dominated by a complex TG decay indicating a simultaneous H 2 O delivery coupled with a disproportionation of [H 2 P 2 O 6 ] 2– , what is also supported by Raman spectra of heated samples.

Description: Three metal coordination polymers {[Co(L) 2 (H 2 O) 2 ] 2+ · 2NO 3 – } n ( 1 ), {[Mn(L) 2 (H 2 O) 2 ] 2+ · 2Cl – · 3H 2 O} n ( 2 ), and [ZnL(ba) 2 ] n ( 3 ) [L = 3, 5-bis(imidazole-1-yl)pyridine and Hba = benzoic acid] were synthesized and structurally characterized by IR spectroscopy, elemental analysis, X-ray powder diffraction, and X-ray single crystal diffraction. Complex 1 shows a one-dimensional (1D) chain structure. Adjacent chains are connected by hydrogen bonding and nitrate groups to form a 3D network. Complex 2 features a 2D layer structure. A three-dimensional network is constructed through the cluster consisting of two chloride ions and three water molecules. Complex 3 shows a 1D zigzag chain structure that further twists together to form a 3D network. The X-ray powder diffraction patterns were compared with the simulated ones. Moreover, the luminescent properties of 1 – 3 were investigated in the solid state at room temperature, and the thermogravimetric analyses were carried out to study the thermal stability of the three complexes.

Description: . The reactions of FeCl 3 · 6H 2 O and 2-(2′-hydroxyphenyl)-2-thiazoline as a bidentate O-N donor thiazoline ligand (thoz) afford a five-coordinate Fe III complex [Fe(thoz) 2 Cl] with a distorted square pyramidal configuration. Complex [Fe(thoz) 2 Cl] was isolated as air-stable crystalline solids and fully characterized, including by single-crystal X-ray structure analysis. Complex [Fe(thoz) 2 Cl] shows very efficient reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide (UHP) as the oxidant at room temperature in air.

Description: Two copper(I) complexes of compositions [Cu(HL)I] 2 · EtOH ( 1 ) and [Cu(HL) 3 ]I · MeOH ( 2 ) were synthesized via the reactions of HL [HL = 2(4, 5-diphenyl-1 H -imidazol-2-yl)pyridine] and CuI in EtOH and MeOH, respectively, under solvothermal conditions. The complexes were characterized by X-ray single crystal diffraction, IR spectroscopy, and elemental analysis. Compounds 1 and 2 are catalytically active towards ketalization reaction, giving various ketals under mild conditions.

Description: Mineral samples from the Prasolovskoe epithermal Au-Ag deposit, Russia, were investigated via transmission electron microscopy (TEM). One component was identified as the mineral kurilite Ag 8 Te 3 Se according to the data obtained from electron diffraction (ED) and Fourier transform analyses of high resolution micrographs. Micrometer-sized grains of kurilite were found next to other noble metal chalcogenide domains like the hessite-type. The EDX microprobe analyses of the kurilite domains were determined with the chemical composition Ag 7.9 Au 0.1 Te 2.9 Se 1.0 which is consistent with kurilite doped by gold. Additionally noble metal polychalcogenidehalides (NMPH) were identified via ED. Monoclinic and tetragonal polymorphs of Ag 5 Te 2 Cl were observed for the first time in a mineral sample. One additional component, whose composition equates the kurilite-type component with regard to Ag, Au, Te, and Se but with a marginal chlorine component, crystallizes in a structure type known from synthetic NMPH, namely Ag 23 Te 12 X (X = Cl, Br). This phase as well as the phases Ag 10 Te 4 Br 3 and Ag 20 Te 10 Br 2 was found next to each other in an also investigated synthetic sample.

Description: Eight chelating resins were synthesized in high yields by supporting 2-aminomethylpyridine, 2, 2′-dipyridylamine, 1, 2-phenylenediamine and 1, 2-ethylenediamine on Merrifield and Wang resins, respectively. These resins were used both as support of reducing complexes and as alkali metal sensors. 16 stable and easy to prepare reducing complexes, derived from the chelating resins and LiBH 4 and NaBH 4 , were prepared in good yields. These complexes showed chemoselectivity to reduce aldehydes in a low molar ratio and short time reactions. The fluorescence-sensing behavior of the chelating resins for alkali metal was studied. The fluorescence response of the materials where 1, 2-phenylenediamine is supported on Merrifield and Wang resins indicate that they behave as sensors for Li + and K + , respectively.

Description: The reaction of Fe 3 (CO) 12 with (C 3 H 5 ) 2 NCS 2 K in THF at room temperature afforded a red-brown solution. Treatment of the thus-obtained solution with MeI and PhCH 2 Br afforded clusters 1 , (μ-MeS)Fe 2 (CO) 6 (μ 4 -S)Fe 2 (CO) 6 (μ-CN(C 3 H 5 ) 2 ), and 2 , (μ-PhCH 2 CO)Fe 2 (CO) 6 (μ 4 -S)Fe 2 (CO) 6 (μ-CN(C 3 H 5 ) 2 ). Their structures were unambiguously determined by X-ray crystallography. Therefore, this methodology provides a novel route for the syntheses of spiro-S Fe/S clusters with aminocarbyne ligands.

Description: This study presents the preparation of 5-azido-3-nitro-1 H -1,2,4-triazole ( 1 ) in both good yield and high purity, starting from commercially available chemicals in a three step synthesis. Furthermore, several metal and nitrogen-rich salts with sodium ( 3 ), potassium ( 4 ), cesium ( 5 ), silver ( 6 ), lead ( 7 ), ammonium ( 8 ), guanidinium ( 9 ), and aminoguanidinium ( 10 ) were prepared by simple acid-base reactions. All compounds were well characterized by various means, including vibrational (IR, Raman) and multinuclear ( 1 H, 13 C, 14 N, 15 N) NMR spectroscopy, mass spectrometry, and DSC. Additionally the structure of 7 was determined by single-crystal X-ray diffraction. The sensitivities towards various outer stimuli (impact, friction, electrostatic discharge) were determined according to BAM standards. The metal salts were tested as potential primary explosives utilizing various preliminary tests.

Description: With Sharpless' and Meldal's discovery of the immensely supportive effect that metal catalysis has on Huisgen's classical 1,3-dipolar cycloaddition, azides (RN 3 ) – long underappreciated in organic synthesis – suddenly got in the focus of attention as most crucial players in sensational ‘click chemistry'. Less noisy though with the same commitment and even a much broader scope of scientific topics and objectives, the inorganic azide chemistry has made just as great strides in the last few decades. This review (Part I) gives an introductory survey of the most important results, and informs about modern developments and general trends. Particular emphasis is placed on the recent successful approaches to highly unstable homoleptic azido metal complexes of the main group and early transition elements, as well as on the enormous structural versatility caused by the ‘flexidentate' N 3 – ligand with its unsurpassed bridging capacities. The presentation in this paper of selected compounds and reactions is meant, in a way, as a prelude to the [3+2]-cycloadditions of metal azides and related species which will be covered in-depths in Part II. A large part of the comments finally deals with applications in fields such as catalysis, high explosive performance or magnetism of metal compounds containing azide, today certainly one of the most attractive research areas world-wide.

Description: The long-chain ligand, 1-phenyl-3-methyl-4-heptanoyl-pyrazol-5-one (HL) and its zinc(II) complex ZnL 2 were synthesized. The structure and the properties of ZnL 2 were characterized by elemental analysis, IR spectroscopy, X-ray diffraction, and thermogravimetric analysis. The zinc ion is five-coordinated in a square-pyramidal environment by four oxygen atoms of the HL ligands in the equatorial plane and one water molecule in the axial position. The water molecule is directly bonded to Zn 2+ and involved in intermolecular hydrogen bonding network. The complex and its corresponding ligand were screened in vitro against some strains of the human pathogenic bacteria. The metal complex exhibits higher antibacterial activity than its corresponding ligand. The complex exhibits purple effect emission as the result of fluorescence from the intraligand emission excited state.

Description: The microporous metal-organic framework Cd 2 (ABTC)(H 2 O)(DMA) 2 · H 2 O · 3DMA ( 1 ) (H 4 ABTC = 3,3′,5,5′-azobenzenetetracarboxylic acid; DMA = N , N ′-dimethylacetamide) was prepared by solvothermal reaction and characterized. X-ray structure analysis revealed that compound 1 is a three-dimensional (3D) open framework with 2D channels. The topology is based on a PtS net, constructed of 4-connected rectangular ABTC 4– units with 4-connected tetrahedral dinuclear Cd 2 (CO 2 ) 4 (H 2 O)(DMA) 2 secondary building units (SBUs). The solid-state excitation-emission spectra showed that the strongest emission peak is at 403 nm upon excitation at λ = 287 nm.

Description: P(2-SHC 6 H 4 ) 3 ( PS 3 H 3 ) reacts with GaMe 3 (1:1) to give GaMe{P(2-SC 6 H 4 ) 2 (2-SHC 6 H 4 )-κ 3 S , S′,P } ( 1 ), which could be deprotonated with NEt 3 to give [NEt 3 H][GaMe{P(2-SC 6 H 4 ) 3 -κ 3 S , S′,P }] ( 2 ). The 1:2 reaction of E (2-SHC 6 H 4 ) 3 [ E = P ( PS 3 H 3 ), As ( AsS 3 H 3 )] with GaMe 3 gave the dinuclear complexes GaMe{ E (2-SC 6 H 4 ) 2 (2-S{GaMe 2 (THF)}C 6 H 4 )-κ 3 S , S′,E } [ E = P ( 3 ), As ( 4 )]. Serendipitous hydrolysis of 4 resulted in small amounts of the hexanuclear gallium hydroxide complex cyclo -{GaMe(μ-OH)} 6 {As(2-SC 6 H 4 ) 3 -κ S , S′,S′′ } 2 ( 5 ). Complexes 1 – 4 were fully characterized, complexes 2 – 5 also by X-ray crystallography.

Description: Topological aspects of the experimental electron density in TiB 2 reconstructed on base of the multipole model are obtained from high-resolution single-crystal X-ray diffraction data. The features of electron density are compared with quantum chemical calculations and analysed in terms of Quantum Theory of Atoms in Molecules for the interpretation of atomic interactions. In spite of some differences in the Laplacian, both experimental and calculated density confirmed two main bonding interactions. The B–B bond critical point suggests a shared-type interaction with pronounced ellipticity in the boron layer, whereas B–Ti bond critical point reveals an interaction intermediate between shared and closed-shell type. Both, theory and experiment indicate a non-structured spherical topology in the penultimate shell of Ti. Integration of the electron density over the atomic basins reveals a charge transfer of 1.1 e (experiment) and 1.4 e (theory) from titanium to boron network, respectively.

Description: The stannides Li 2 CuSn 2 and Li 2 AgSn 2 were synthesized by induction-melting (or in a muffle furnace) of the elements in sealed niobium ampoules. The new phases were characterized by powder X-ray diffraction. The structures of both stannides were investigated by X-ray diffraction on single crystals: Li 2 AuSn 2 type, I 4 1 / amd , a = 442.6(1), c = 1940.9(8) pm, wR 2 = 0.0742, 310 F 2 values for Li 2 CuSn 2 and a = 456.33(9) c = 2018.2(6) pm, wR 2 = 0.0626, 339 F 2 values for Li 2 AgSn 2 with 10 variables for each refinement. The transition metal ( T ) atoms have tetrahedral tin coordination. The T Sn 4 tetrahedra are condensed via common corners forming layers that are further condensed by Sn–Sn bonding, leading to three-dimensional [CuSn 2 ] and [AgSn 2 ] networks which leave distorted hexagonal channels for the lithium atoms. The lithium ions show considerable mobility, with activation energies of 0.29 and 0.47 eV extracted from variable temperature 7 Li solid state NMR spectra. 119 Sn Mössbauer spectra at 78 K show signals at isomer shifts of δ = 2.13(1) mm s –1 for Li 2 CuSn 2 and δ = 2.07(1) mm s –1 for Li 2 AgSn 2 . The signals show electric quadrupolar splitting because of the non spherical environment of the tin nuclei. A minor impurity of β-Sn could be identified in both spectra.

Description: The complexes [Ni 2 (L) 2 ] 2 · H 2 O ( 1 ) and [Cu 2 (L) 2 (H 2 O)] · 2CH 3 OH ( 2 ) were prepared by reaction of the chiral Schiff base ligand N -[(1 R ,2 S )-2-hydroxy-1, 2-diphenyl]-acetylacetonimine (H 2 L) with Ni II and Cu II ions, respectively, aiming to develop economically and environmentally-friendly catalysts for the hydrogenation of ketones. They have a dinuclear skeleton with axial vacant sites. The catalytic effects of the two complexes for hydrogenation of ketones were tested using dihydrogen gas as hydrogen source. They present some catalytic effects in hydrogenation of acetophenone, which has a dependence on the temperature and base used in these reactions. However, no apparent catalytic effects were found for the two complexes in hydrogenation of 4-nitroacetophenone and 4-methylacetophenone. Although the catalytic conversion in these hydrogenation reactions is low, they do represent a kind of cheap and environmentally-friendly hydrogenation catalyst.

Description: Poised to investigate the association of vanadium with physiological substrates in materials capable of exerting anticancer biological activity, pH-specific synthetic chemical reactivity between vanadium and triethyl ammonium acetate/trigonelline in aqueous and mixed organic-aqueous media led to the isolation of three new binary composite materials, namely K 2 [(MeN(+)C 5 H 4 COOH) 2 ][V 10 O 28 H 2 ] · 2H 2 O ( 1 ), [(H 2 N(+)Me 2 ) 4 ][V 10 O 28 H 2 ][Me 3 N(+)CH 2 COO(–)] 2 ( 2 ), and [(Me 3 N(+)CH 2 COOH) 4 ][V 10 O 28 H 2 ][Me 3 N(+)CH 2 COO(–)] 2 · 2H 2 O ( 3 ). 1–3 were characterized by elemental analysis, FT-IR and UV/Vis spectroscopy, Cyclic voltammetry, TGA-DTG, and X-ray crystallography. In all three compounds, the [V 10 O 28 H 2 ] 4– core unit is a common cluster assembly, with the vanadium in the +5 oxidation state. The counteracting cationic assembly in each composite material originates in the betaine starting reagent or the solvent out of which the materials crystallized. Biological activity studies of 1 and 3 in vitro in MCF-7 breast epithelial and A549 lung adenocarcinoma cell cultures show that both materials inhibit the viability of both cell lines in a dose-dependent fashion, in juxtaposition to the behavior of the betaine components present in these materials. Collectively, the herein studies a) reveal the uniquely defined synthetic methodologies and physicochemical properties of the variably assembled [V 10 O 28 H 2 ] 4– core units crystallized into the composite binary polyoxovanadate-betaine lattice structures, b) unravel the distinct cytotoxicity profile of the composite materials toward MCF-7 and A549 cells, and c) attest to their future potential as metallodrugs of pharmacological significance in anticancer activity.

Description: The crystal structures of the alkali aluminium thiohypodiphosphates M I AlP 2 S 6 (M I = Li, Na) are reported. NaAlP 2 S 6 crystallizes in the orthorhombic space group Fdd 2 (no. 43) with a = 8.0400(2), b = 10.9452(2), c = 20.8801(4) Å, and V = 1837.44(7) Å 3 ( Z = 8). It is isostructural with AgAlP 2 S 6 , which is consistent with the similar ionic radii of Na and Ag. In contrast, LiAlP 2 S 6 crystallizes in a different structure type which has not been observed in the large number of thiohypodiphosphates reported so far. It crystallizes in the monoclinic space group C 2/ c (no. 15) with a = 6.783(3), b = 10.365(4), c = 11.776(4) Å, β = 94.399(5)°, and V = 825.46(5) Å 3 ( Z = 4).