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  • 1
    Electronic Resource
    Electronic Resource
    Synthese und Charakterisierung heterobimetallischer Bis(trimethylsilyl)phosphanide von Barium und Zinn (1995)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 877-888 
    Details
    ISSN: 0044-2313
    Keywords: Barium ; Bis(trimethylsilyl)phosphanide ; Phosphanide ; Tin ; NMR ; X-ray Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Characterization of Hetero-bimetallic Bis(trimethylsilyl)phosphanides of Barium and TinThe reaction of barium bis[bis(trimethylsilyl)amide] with one equivalent of bis(trimethylsilyl)phosphane in 1,2-dimethoxyethane (dme) yields the heteroleptic dimeric (dme)barium bis(trimethylsilyl)amide bis(trimethylsilyl)phosphanide. This colorless compound crystallizes in the monoclinic space group P21/n with a = 1 259.1(3), b = 1 822.7(4), c = 1 516.1(3) pm, β = 110.54(3)° and Z = 4. The central moiety of the centrosymmetric molecule is the planar Ba2P2-cycle with Ba—P-bond lengths of 329 and 334 pm. In the presence of bis[bis(trimethylsilyl)amino]stannylene hetero-bimetallic bis(trimethylsilyl)phosphanides of tin(II) and barium are isolated. If the reaction of Ba[N(SiMe3)2]2 and Sn[N(SiMe3)2]2 in the molar ratio of 1:2 with six equivalents of HP(SiMe3)2 is performed in toluene, barium bis{tin(II)-tris[bis(trimethylsilyl)phosphanide]} can be isolated. This compound crystallizes in the orthorhombic space group P212121 with a = 1 265.1(1), b = 2 290.1(3), c = 2 731.9(3) pm and Z = 4. The anions {Sn[P(SiMe3)2]3}- bind as two-dentate ligands to the barium atom which shows the extraordinary low coordination number of four. The addition of tetrahydrofuran (thf) to the above mentioned reaction solution leads to the elimination of tris(trimethylsilyl)phosphane and the formation of thf complexes of barium bis{tin(II)-bis(trimethylsilyl)phosphanide-trimethylsilylphosphandiide}. The derivative crystallizes from toluene in the monoclinic space group P21/c with a = 1 301.9(2), b = 2 316.3(3), c = 3 968.7(5) pm, β = 99.29(1)° and Z = 8.
    Notes: Bei der Reaktion von Barium-bis[bis(trimethylsilyl)amid] mit einem Äquivalent Bis(trimethylsilyl)phosphan in 1,2-Dimethoxyethan (DME) wird heteroleptisches, dimeres (1,2-Dimethoxyethan-O,O′)barium-bis(trimethylsilyl)-amid-bis(trimethylsilyl)phosphanid isoliert. Diese farblose Verbindung kristallisiert in der monoklinen Raumgruppe P21/n mit a = 1 259,1(3), b = 1 822,7(4), c = 1 516,1(3) pm, β = 110,54(3)° und Z = 4. Das zentrale Strukturelement des zentrosymmetrischen Moleküls ist der planare Ba2P2-Cyclus mit Ba—P-Bindungslängen von 329 und 334 pm. In Gegenwart des Bis[bis(trimethylsilyl)amino]stannylens erhält man heterobimetallische Bis(trimethylsilyl phosphanide von Zinn(II) und Barium. Wird die Umsetzung von Ba[N(SiMe32]2 and Sn[N(SiMe3)2]2 im molaren Verhältnis 1:2 mit sechs Äquivalenten HP(SiMe3)2 durchgeführt, kann Barium-bis{zinn(II)-tris-[bis(trimethylsilyl)phosphanid]} isoliert werden. Diese Verbindung kristallisiert in der orthorhombischen Raumgruppe P212121 mit a = 1 265,1(1), b = 2 290,1(3), c = 2 731,9(3) pm und Z = 4. Die Anionen {Sn[P(SiMe3)2])3}- binden als zweizähnige Liganden an das Bariumatom, das dadurch die ungewöhnlich niedrige Koordinationszahl vier aufweist. Die Zugabe von THF zu der oben beschriebenen Reaktionslösung führt zur Eliminierung von Tris(trimethylsilyl)phosphan und der Bildung von Barium-bis{zinn(II)-bis(trimethylsilyl)phosphanid-trimethylsilylphosphandiid). Das Derivat kristallisiert aus Toluol in der monoklinen Raumgruppe P21/c mit a = 1 301,9(2), b = 2 316,3(3), c = 3 968,7(5) pm, β = 99,29(1)° und Z = 8.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19956210529
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  • 2
    Electronic Resource
    Electronic Resource
    Trimethylstannyl- und Dimethylstannyl-substituierte Pyrrole - Synthesen, Spektren und Strukturen (1995)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 1785-1796 
    Details
    ISSN: 0044-2313
    Keywords: Organotin pyrrole derivatives ; NMR, vibrational spectra, X-ray structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Trimethylstannyl- and Dimethylstannyl-substituted Pyrroles - Synthesis, Spectra, and StructuresMonomeric trimethylstannyl pyrroles, Me3Sn—R (Me = CH3 and R = —NC4H4, —NC4H2Me2-2,5, —NC4Me4-2,3,4,5, —C4H3NMe-1), are synthesized by metathesis reactions from Me3SnCl with 1(N)- and 2(C)-lithium pyrroles, respectively. An almost similar procedure gives monomeric dimethylstannylbis(pyrroles), Me2SnR2 (1 a - 3 a), from Me2SnCl2 and 1-Li-pyrrolides (1 : 2 molar ratio) in good yields. Lithiated 1,2,5-trimethylpyrrole and Me3SnCl forms the compound Me3Sn—CH2—C4H2Me(-5)NMe (8), the reaction of Me2SnCl2 with 2-lithium-1-methylpyrrole gives oligomeric [Me2Sn—C4H2NMe—]x, (6 a). The mass-, NMR, and vibrational spectra have been measured and discussed. The results of the X-ray structure determinations of Me3Sn—NC4H4 (1) and Me2Sn(—NC4Me4)2 (3 a) are compared with the structures of the known dimethylmetal pyrroles of Al, Ga, and In.
    Notes: Monomere Trimethylstannylpyrrole, Me3Sn—R (Me = CH3, R = —NC4H4, —NC4H2Me2-2,5, —NC4Me4-2,3,4,5, —C4H3NMe-1), werden durch Metathese aus Me3SnCl und 1(N)- bzw. 2(C)-lithiierten Pyrrolen synthetisiert. Analog hierzu werden aus Me2SnCl2 und Li—N Pyrroliden (Molverhältnis 1 : 2) die ebenfalls monomeren Dimethylstannylbis(pyrrole), Me2SnR2 (1a - 3a), in guten Ausbeuten erhalten. Einfach lithiiertes 1,2,5-Trimethylpyrrol bildet mit Me3SnCl die Verbindung Me3Sn—CH2—C4H2Me(-5)NMe (8); die Umsetzung von Me2SnCl2 mit 2C-lithiiertem 1-Methylpyrrol ergibt oligomeres [Me2Sn—C4H2NMe—]x (6 a). Die Massen-, Kernresonanz- und Schwingungsspektren werden aufgenommen und diskutiert. Die Ergebnisse der Röntgeneinkristallstrukturanalysen von Me3Sn—NC4H4 (1) und Me2Sn(—NC4Me4)2 (3 a) werden mit den Strukturdaten der bekannten Dimethylmetallpyrrole des Al, Ga und In Verglichen.
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19956211030
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  • 3
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    Electronic Resource
    1,2-Bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolan und 1,2-Bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborin: Synthese und Struktur sowie Berechnungen zur MolekülstrukturProfessor Hans-Georg von Schnering zum 65. Geburtstage gewidmet (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 1462-1470 
    Details
    ISSN: 0044-2313
    Keywords: 1,2-Bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolane ; 1,2-bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborine ; preparation ; NMR ; molecular structures ; ab initio calculations ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,2-Bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolane and 1,2-Bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborine: Synthesis and Structure as well as Calculations on the Molecular StructureThe diphosphides K2[(C6H5)P—(C6H5)P—P(C6H5)], 4 or K2[(tBuP)—(tBuP)2—P(tBu)], 5, react with (ClBNMe2)2 to form the binary 5-membered ring system 1,2-bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolane (C6H5P)3(BNMe2)2, 2a, and the 6-membered ring system 1,2-bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborine, (tBuP)4(BNMe2)2, 3a, respectively. 2a and 3a could be obtained in a pure form and characterized NMR spectroscopically and by X-ray structure analyses. The two ring systems are folded; 2a exists in the „envelope“- 3a in the „boat“-conformation. Ab initio computations for 3,4,5-triphospha-1,2-diborolane M5 show that the global minimum is characterized by one B—P double bond. The parent compound geometry M6 is characterized by transannular bonding in the PH—BH—BH—PH moiety which differs in character from those in the four- and five-membered rings (BH)2(PH)2 and (BH)2(PH)3 M5 d, respectively. Explicit calculation of the influence of amino substituents on boron improved agreement of the bond length between computed and X-ray data.
    Notes: Die Diphosphide K2[(C6H5)P—(C6H5)P—P (C6H5)], 4, bzw. K2[(tBuP)—(tBuP)2—P(tBu)], 5, reagieren mit (ClBNMe2)2 zu dem binären Fünfringsystem 1,2-Bis(dimethylamino)-3,4,5-triphenyl-3,4,5-triphospha-1,2-diborolan (C6H5P)3(BNMe2)2, 2a, bzw. dem Sechsringsystem 1,2-Bis(dimethylamino)-3,4,5,6-tetra-tbutyl-3,4,5,6-tetraphospha-1,2-diborin, (tBuP)4(BNMe2)2, 3a. 2a und 3a konnten in reiner Form isoliert, NMR-spektroskopisch und durch Röntgenstrukturanalysen charakterisiert werden. Beide Ringsysteme sind gefaltet; 2a zeigt eine „envelope“- 3a eine „Wannen“-Konformation.Ab initio Berechnungen an 3,4,5-Triphospha-1,2-diborolan M5 zeigen, daß im globalen Minimum eine B—P-Doppelbindung mit annähernd planarem σ3-Phosphor vorliegt. Die Geometrie der Stammverbindung des Sechsringes M6 weist „durch-den-Ring“-Bindung in der PH—BH—BH—PH-Baugruppe auf, welche sich von jenen im Vier- und Fünfring M5 d unterscheidet. Durch die explizite Berechnung des Einflusses von Aminosubstituenten an Bor auf die Geometrien des Fünf- und Sechsringes verbessert sich die Übereinstimmung der Bindungslängen mit den Daten der Röntgenstrukturanalyse.
    Additional Material: 7 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19966220906
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  • 4
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    Electronic Resource
    N,N′ -Disilylated 1,4-Dihydropyrazines: Organosilyl Substitution Reactions, Structural Effects of Steric Hindrance, and Electron Exchange with C60 (1995)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 128 (1995), S. 745-750 
    Details
    ISSN: 0009-2940
    Keywords: Silicon compounds ; Hydrogen-hydrogen contacts ; Radicals ; ENDOR spectroscopy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Organosilyl exchange reactions of the extremely electronrich and formally “antiaromatic” 1,4-bis(trimethylsilyl)-substituted 1,4-dihydropyrazine 1 with Ph3SiCl or Me5Si2Cl yielded the new compounds 2 and 3 with triarylsilyl and disilanyl substituents. At δ = 4.53 in CDCl3 compound 3 shows a particularly high-field shifted 1H-NMR resonance for the 1,4-dihydropyrazine protons. In contrast to the planar ring arrangement of 1,4-bis(triisopropylsilyl)-1,4-dihydropyrazine 4, the crystal structure determination of the 2,5-dimethylated analogue 5 as obtained by reductive silylation exhibits a pronounced boat conformation of the heterocycle due to steric repulsion between the substituents, the closest H…H (CH3/ CH) contact being 211 pm. Despite the sizeable structural differences between 4 and 5 both compounds are reversibly oxidized at very negative potentials, at -0.90 and -0.85 V vs. Fc+/0, respectively, It appears that the electrochemical behavior of this class of compounds is determined ***primarly by the configuration at the nitrogen centers and less by the ring conformation. Compound 4 reacts with C60 under EPR-detectable electron exchange to afford 4+* and C-*60. The radical cation 4+* generated separately via oxidation with iodine was characterized by low-temperature UV/Vis and ENDOR spectroscopy. An ENDOR spectrum revealing silylalkyl coupling was also obtained for the related radical cation of reversibly oxidizable 1,1′ -bis(tert-butyldimethylsilyl)-1,1′,4,4′ -bipyridylidene (8).
    Additional Material: 4 Ill.
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    URL: http://dx.doi.org/10.1002/cber.19951280802
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  • 5
    Electronic Resource
    Electronic Resource
    Zwei neue Alkylimido-methylgallane mit KäfigstrukturProfessor Kurt Dehnicke zum 65. Geburtstag gewidmet (1996)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 622 (1996), S. 573-578 
    Details
    ISSN: 0044-2313
    Keywords: Alkylimido-methylgallanes ; synthesis ; NMR vibrational spectra X-Ray structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Two New Alkylimido-Methylgallanes with Cage StructureThe tetrameric alkylimido-methylgallanes (MeGa—NR)4 (R = CH(CH3)2 ( iPr), C(CH3)3 ( tBu) and Me = CH3) have been prepared by pyrolyses of the dimeric amido compounds (Me2Ga—N(H)R)2 at 250-260°C. The mass, NMR and vibrational spectra are discussed, they prove almost identical structures of the skeletons. The X-Ray structure determination of (MeGa—NtBu)4 shows four heterocubane molecules in the trigonal unit cell (space group P3c1, a = b = 1061.7(1), c = 3191.8(5) pm) and two disordered benzene solvate molecules. The Ga—N bonds range between 198.4 to 199.9 pm, the Ga—N—Ga and N—Ga—N bond angles lie between 90.6 to 91.4 and 88.6 to 89.2°, respectively. The structure was refined to an R1(R2)-value of 0.049 (0.057).
    Notes: Die tetrameren Alkylimido-methylgallane (MeGa—NR)4 (R = CH(CH3)2 ( iPr), C(CH3)3 ( tBu) und Me = CH3) sind durch Pyrolyse der dimeren Amidoverbindungen (Me2Ga—N(H)R)2 bei 250-260°C dargestellt worden. Die Massen-, Kernresonanz- und Schwingungsspektren werden diskutiert; sie bestätigen weitgehend übereinstimmende Gerüststrukturen. Die Röntgenstrukturanalyse von (MeGa—NtBu)4 zeigt vier Heterocubanmoleküle in der trigonalen Einheitszelle (Raumgruppe P3c1, a = b = 1061,7(1), c = 3191,8(5) pm) sowie zwei fehlgeordnete Benzol-Solvatmoleküle. Die Ga—N-Bindungslängen liegen zwischen 198,4 und 199,9 pm, die Ga—N—Ga bzw. N—Ga—N-Valenzwinkel zwischen 90,6 und 91,4° bzw. 88,6 und 89,2°. Die Struktur wurde bis zu einem R1(R2)-Wert von 0,049 (0,057) verfeinert.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19966220331
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  • 6
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    Electronic Resource
    Die Kristallstruktur von tert-Butylimidomethylindan, [CH3In—NC(CH3)3]4 (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1499-1500 
    Details
    ISSN: 0044-2313
    Keywords: Methylindium Compound ; Heterocubane ; Synthesis ; X-ray Structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The X-Ray Structure Determination of tert-Butylimido Methylindane, [CH3In—NC(CH3)3]4The reaction of MeInCl2 with LiN(H)tBu in a 1 : 2 molar ratio forms [MeIn—NtBu]4 in high yield, lithium chloride, and the free amine H2NtBu. The crystal structure of the imidomethylindane with a cubic In4N4 skeleton has been determined.
    Additional Material: 1 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19976231004
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  • 7
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    Electronic Resource
    Base-freie Tris(trimethylsilyl)methyl-Derivate des Lithiums, Aluminiums, Galliums und Indiums (1997)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1455-1466 
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    ISSN: 0044-2313
    Keywords: Tris(trimethylsilyl)methyl-derivatives, Lithium, Aluminium, Gallium, Indium ; spectra ; X-ray Structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Base-free Tris(trimethylsilyl)methyl Derivatives of Lithium, Aluminium, Gallium, and IndiumBase-free LiR* (R*=-C(SiMe3)3) has been prepared from R*Cl and Li-metal in toluene at 85-90°C and used to synthesize the metallanes R*MMe2 with M = Al, Ga and In, respectively. The NMR (1H, 13C, 29Si) and the vibrational spectra of these trisyl compounds have been discussed.AlCl3 and LiR*(ratio 1 : 1) forms the metallate metallate Li[R*AlCl3]. The triclinic unit cell (space group P1) consists of a centrosymmetric assoziate, formed by four Li[R*AlCl3]- units with Al—Cl…Li bridges, two pairs of Li-atoms differing in their chlorine-coordination and two disordered toluene molecules, inserted in the crystal lattice (R1wR2 =0,0444/0,1072).The reaction of GaCl3 with LiR* (I :1) gives the unusual sesquichloride (R*Ga(Cl1,33)Me0,67)3 in moderate yield. The X-ray structure determination shows a Ga3Cl3-skeleton with chairconformation and disordered, terminal gallium ligands (R1/wR2= 0,0646/0,2270).
    Notes: Basefreies LiR* (R*=-C(SiMe3)3) wurde aus R*Cl und Lithiummetall in Toluol bei 85-90°C erhalten und zur Darstellung der Dimethylmetallane R*MMe2 mit M = Al, Ga, In verwendet, die durch NMR- (1H, 13C, 29Si) und Schwingungsspektren (Raman, IR) charakterisiert werden.AlCl3 und LiR* (Molverhältnis 1 : 1) bilden das Metallat Li[R*AlCl3]. Die trikline Einheitszelle (Raumgruppe P1) enthält ein zentrosymmetrisches, über Al—Cl … Li—Brücken gebildetes Assoziat aus vier Li[R*AlCl3]-Einheiten, mit zwei paarweise unterschiedlich von Chlor koordinierten Li-Atomen sowie zwei fehlgeordnete Toluolmoleküle (R1/ wR2 = 0,0444/0,1072).Die Reaktion von GaCl3 mit LiR* (1 : 1) in Toluol führt in mäßiger Ausbeute zum ungewöhnlichen Sesquichlorid (R*Ga(Cl1,33)Me0,67)3. Die Röntgenstrukturanalyse zeigt ein sesselförmig gewelltes Ga3Cl3-Sechsringgerüst und fehlgeordnete, terminale Liganden am Galliumatom (R1/ wR2 = 0,0646/0,2270).Li[R*AlCl3]. The triclinic unit cell (space group P1) consists of a centrosymmetric assoziate, formed by four Li[R*AlCl3]-units with Al-Cl … Li bridges, two pairs of Li-atoms differing in their chlorine-coordination and two disordered toluene molecules, inserted in the crystal lattice (R1/wR2 = 0,0444/0,1072).The reaction of GaCl3 with LiR* (1 : 1) gives the unusual sesquichloride (R*Ga(Cl1,33)Me0,67)3 in moderate yield. The X-ray structure determination shows a Ga3Cl3-skeleton with chairconformation and disordered, terminal gallium ligands (R1/wR2 = 0,0646/0,2270).
    Additional Material: 3 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19976230922
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  • 8
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    Electronic Resource
    1,2-Diphospha-3,4-diboretane und 1,3-Diphospha-2,4,5-triborolan: Synthese und Struktur sowie Berechnungen zur Molekülstruktur Über den Einfluß von Substituenten auf die Struktur von 1,2-Diphospha-3,4-diboretan (1995)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 1111-1122 
    Details
    ISSN: 0044-2313
    Keywords: 1,2-Diphospha-3,4-diboretanes ; 1,3-diphospha-2,4,5-triborolane derivative ; preparation ; molecular structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,2-Diphospha-3,4-diboretanes and 1,3-Diphospha-2,4,5-triborolane: Synthesis and Structure as well as Calculations on the Molecular Structure On the Effect of Substituents on the Structure of 1,2-Diphospha-3,4-diboretane[2 + 2]-Cyclocondensation reactions led to the synthesis of the 1,2-diphospha-3,4-diboretanes [(t-BuP)2B2(NMe2)2], 1 a, and [(t-BuP)2B(NMe2)B(NiPr2)], 1 b. Their molecular structures have been determined by X-ray methods, and these are compared with the structure of [(t-Bu)P—BN(iPr2)]2, 2 a. Compounds 1 show a folded B2P2 four membered ring having tert.-butyl groups in anti-positions. Ab initio calculations on 1,2-diphospha-3,4-diboretanes demonstrate that two conformers with anti-orientation of the substituents at the phosphorus atoms can be expected. These differ by the relative orientation of the almost planar P2BR groups to the BP2 plane. The influence of substituents (H and NH2 at the B atoms, and H and Me at the P atoms) on the ring conformation has been studied. Finally, the first derivative of a 1,3-diphospha-2,4,5-triborolane, 3 a, is reported.
    Notes: Durch [2 + 2]-Cyclokondensationen wurden die 1,2-Diphospha-3,4-diboretane [(t-BuP)2B2(NMe2)2], 1 a, und [(t-BuP)2B(NMe2)B(NiPr2)], 1 b, dargestellt, ihre Molekülstrukturen mit Röntgenbeugungsmethoden bestimmt und mit der Struktur von [(t-Bu)P—B(NiPr2)]2, 2 a, verglichen. In den Verbindungen 1 liegen gefaltete B2P2-Vierringe vor mit anti-ständigen tert.-Butylgruppen, während das Ringsystem in 2 a planar gebaut ist, die tert.-Butylgruppen aber ebenfalls anti-Stellung einnehmen. Ab initio-Rechnungen an 1,2-Diphospha-3,4-diboretanen belegen, daß zwei unterschiedliche Konformere mit anti-Orientierung der Substituenten an den P-Atomen stabil sind, die sich durch die relative Orientierung der annähernd trigonal-planaren P2BR-Baugruppen zur BP2-Ebene voneinander unterscheiden. Der Einfluß von Substituenten (H und NH2 am B-Atom, H und CH3 am P-Atom) wird ermittelt. Beschrieben wird ferner das erste Derivat eines 1,3-Diphospha-2,4,5-triborolans, 3 a.
    Additional Material: 8 Ill.
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    URL: http://dx.doi.org/10.1002/zaac.19956210702
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  • 9
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    Dimethylgallium-bis(trimethylsilyl)phosphan Schwingungsspektrum, Kraftkonstanten und Struktur (1995)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 1351-1357 
    Details
    ISSN: 0044-2313
    Keywords: Dimethylgallium-bis(trimethylsilyl)phosphane, X-ray structure, vibrational spectrum, force constants ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Dimethylgallium-bis(trimethylsilyl)phosphane, Vibrational Spectrum, Force Constants, and X-Ray StructureDimeric dimethylgallium-bis(trimethylsilyl)phosphane, [Me2Ga—P(SiMe3)2]2, (Me = CH3) is synthesized from Me2GaCl and P(SiMe3)3 in hot toluene. The compound crystallizes in the triclinic space group P1 with the cell parameters a = 909.8(2), b = 960.5(2), c = 971.6(2) pm; α = 76.75(1)°, β = 80.35(1)°, γ = 63.94(1)° and Z = 1 (dimer). The Ga—P distances are 244.8 and 245.2 pm, the ring angles are 91.8° (Ga—P—Ga) and 88.2° (P—Ga—P), respectively. The vibrational spectrum (IR and Raman for the solid) has been measured and assigned; force constants calculations are carried out for the skeleton [C2Ga—P(SiC3)2]2 using Fleischhauers [26] PC-program.
    Notes: Dimeres Dimethylgallium-bis(trimethylsilyl)phosphan, [Me2Ga—P(SiMe3)2]2 (Me = CH3), wird aus Me2GaCl und P(SiMe3)3 in heißem Toluol synthetisiert. Die Verbindung kristallisiert in der triklinen Raumgruppe P1 mit den Gitterkonstanten a = 909,8(2), b = 960,5(2), c = 971,6(2) pm; α = 76,75(1)°, β = 80,35(1)°, γ = 63,94(1)° und Z = 1 (Dimer). Die Ga—P-Abstände des planaren Ga2P2-Gerüsts betragen 244,8 und 245,2 pm, die Ringwinkel 91,8° (Ga—P—Ga) bzw. 88,2° (P—Ga—P). Das Schwingungsspektrum (IR und Raman des Feststoffs) wurde aufgenommen und zugeordnet, für das Molekülskelett [C2Ga—P(SiC3)2]2 werden mit dem PC-Programm von Fleischhauer [26] Kraftkonstantenrechnungen durchgeführt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19956210813
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  • 10
    Electronic Resource
    Electronic Resource
    Synthese und Strukturbestimmung von (tBuP)4Sn(CH3)2 und (CH3)2Sn[(tBu)P—P(tBu)]2Sn(CH3)2 (1995)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 1358-1364 
    Details
    ISSN: 0044-2313
    Keywords: Phosphorus tin heterocycles ; syntheses ; crystal structure ; NMR ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Structure Analysis of (tBuP)4Sn(CH3)2 and (CH3)2Sn[(tBu)P—P(tBu)]2Sn(CH3)2The diphosphides K2[(tBu)P—(tBuP)2—P(tBu)] 7 or K2[(tBu)P—P(tBu)] 8 react with (CH3)2SnCl2 in a molar ratio of 1 : 1 to form the binary 5-membered ring system P4Sn 4 a and the 6-membered ring system Sn(P2)2Sn 5 a respectively. When (CH3)2SnCl2, however, is treated with 8 in a molar ratio of 2 : 1 the 4-membered ring system P3Sn 2 a is formed which includes the fragmentation of the intermediate K2[(CH3)2Sn ((tBu)P—P(tBu))2] 9. 4 a and 5 a could be obtained in a pure form and characterized NMR spectroscopically and by X-ray structure analyses; 2 a was identified only NMR spectroscopically.
    Notes: Die Diphosphide K2[(tBu)P—(tBuP)2—P(tBu)] 7 bzw. K2[(tBu)P—P(tBu)] 8 reagieren mit (CH3)2SnCl2 im Molverhältnis 1 : 1 zu dem binären Fünfringsystem P4Sn 4 a bzw. dem Sechsringsystem Sn(P2)2Sn 5 a. Wird jedoch (CH3)2SnCl2 mit zwei Äquivalenten 8 umgesetzt, so erhält man nach einer Fragmentierung des Intermediats K2[(CH3)2Sn ((tBu)P—P(tBu))2] 9 das binäre Vierringsystem P3Sn 2 a. 4 a und 5 a konnten in reiner Form isoliert, NMR-spektroskopisch und durch Röntgenstrukturanalysen charakterisiert werden; 2 a konnte bisher nur NMR-spektroskopisch identifiziert werden.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19956210814
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