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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 103 (1970), S. 1522-1535 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of Aromatic Erythrina-Alkaloids, XIV. Application of the Glyoxylester Synthesis to DihydroresorcinolThe monocycloketal 7 of dihydroresorcinol yields, via glyoxylester synthesis, the condensation product 10. On treatment with dilute phosphoric acid, 10 hydrolyses to give the partially hydrogenated ketoisatin derivative 14a which is stabilised by conjugation and cannot be cyclised. In the presence of crystalline phosphoric acid 10 forms a violet cation, Pictet-Spengler cyclisation of which leads to a mixture of stereoisomeric spiroisoquinolines (22). From the mixture two racemates are isolated, the n. m. r. analysis of which permits the assignment of cis- and trans-configurations according to the formulae 22A and 22B.
    Notes: Aus dem Monocycloketal 7 des Dihydroresorcins wird auf dem Weg der Glyoxylestersynthese die Cyclisierungsvorstufe 10 gewonnen. Sie hydrolysiert unter der Einwirkung von verdünnter phosphorsäure zu dem Partiell hydrierten Ketoisatin-Derivat 14a, das durch Konjugation stabilisiert und nicht cyclisierbar ist. Mit kristalliner Phosphorsäure entsteht aus 10 ein violettes Kation, das durch Ringschluß nach Pictet-Spengler zu einem Gemisch stereoisomerer Spiroisochinoline 22 abreagiert. Nach Auftrennung in zwei Racemate wird durch NMR-Analyse die sterische Zuordnung zur cis- und trans-Reihe entsprechend den Formulierungen 22A und 22B ermittelt.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 3800-3812 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bullvaleno-Crown Ethers with Variable Ring SizesSyntheses and properties of the bullvaleno-crown ethers 1a-e are described. An analysis of the temperature dependent 1H NMR spectra proves an easily occurring thermally induced change of ring size within certain limits. The relatively small association constants reveal a weak „guesthost„ interaction of 1a-e with alkali and ammonium rhodanide. The stoichiometry of the complexes and preferred positional isomers of the ligands of the complexes are reported for alkali and ammonium picrates. The possible adaption of the „breathing„ crown ethers to cations of different sizes is not observed.
    Notes: Es werden Synthesen und Eigenschaften der Bullvaleno-kronenether 1a-e beschrieben. Die Analyse der temperaturabhängigen 1H-NMR-Spektren beweist, daß sich die Ringgröße dieser Verbindungen thermisch leicht innerhalb bestimmter Grenzen verändert. Die relativ kleinen Assoziationskonstanten zeigen nur eine schwache „Gast-Wirt“-Wechselwirkung zwischen 1a-e und Alkali- und Ammoniumpikraten sowie tert-Butylammoniumrhodanid an. Die Stöchiometrie der Komplexe und bevorzugte Positionsisomere der Liganden in den Komplexen werden für Alkali- und Ammoniumpikrate angegeben. Die mögliche Adaption der „atmenden“ Kronenether an Kationen verschiedener Größe wird nicht beobachtet.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 112 (1979), S. 1372-1379 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Six- and Eight-membered Sulfur-Nitrogen-Heterocycles - Compounds of Sulfur with the Formal Oxidation States 2, 4, and 6The reaction of the eight-membered compound S4N4O2 with silylamines having several substituents and tris(trimethylstannyl)amine yields the six- and eight-membered heterocycles 1-3. The six-membered rings 1 and, 2 are the first examples where the sulfur atoms have the formal oxidation states 2, 4, and 6. 1 and 2 can also be synthesized by the reaction of silyl- and stannyl-substituted sulfur diimide with N-sulfinylfluorosulfonamide. 2 and 3 are also obtained by the reaction of S4N4O2, with trimethyltin azide. The structure of 2 was determined by an X-ray analysis. 2 crystallizes in the space group P2l. Five of the six-ring atoms form a plane. The nitrogen atom coordinated to the tin lies 78 pm above this plane. The S — N bond lengths are discussed in connection with known structures.
    Notes: Die Umsetzung der Achtringverbindung S4N4O2 mit mehrfach substituierten Silylaminen und Tris(trimethylstannyl)amin führt zu den Sechs- bzw. Achtring-Heterocyclen 1-3. Die Sechsringe 1 und 2 sind die ersten Beispiele, in denen der Schwefel die formalen Oxidationsstufen 2, 4 und 6 erreicht. 1 und 2 lassen sich auch durch Umsetzung von N-Sulfinylfluorsulfonamid mit silyl- oder stannylsubstituiertem Schwefeldiimid darstellen. 2 und 3 sind ebenfalls zugänglich durch die Umsetzung von S4N4O2 mit Trimethylzinnazid. Die Struktur von 2 wurde durch eine Röntgen-analyse aufgeklärt. 2 kristallisiert in der Raumgruppe P21. Fünf der sechs Ringatome bilden eine Ebene, während das Stickstoffatom, welches am Zinnatom gebunden ist. um 78 pm außerhalb der Ringebene liegt. Die S — N-Bindungslängen werden im Zusammenhang mit bisher bekannten Strukturen diskutiert.
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  • 4
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Salts of S4N4O2 - Examples for the Dependence of the Structure of Cyclic Sulfur-Nitrogen Compounds on the Electron DensityThe reaction of S4N4O2 with nucleophiles (alcoholates, alcohols, azides, and isocyanates) in alcoholic solution leads to the salts 1a-h. The Structure of 1h was determined by means of an X-ray analysis. 1h crystallizes in the space group P21/n and contains a transannular S—S-bond with 248.2 (2) pm. The structure of 1h is considered in connection with the increase of electron density and compared with the results of the X-ray analysis of CH3Si(NSN)3SiCH3 (2). 2 is cubic (space group P4132). The bicyclic molecule (S—N 150.4(2), Si—N 173.7 (2) pm) has approximate D3h symmetry and shows no S—S bonds across the rings.
    Notes: Die Umsetzung von S4N4O2 mit Nucleophilen (Alkoholate, Alkohole, Azide und Isocyanate) in alkoholischem Medium führt zu den Salzen 1a-h. Für 1h wurde eine Röntgenstrukturanalyse durchgeführt. 1h kristallisiert in der Raumgruppe P21/n und enthält eine transannulare S—S Bindung mit 248.2 (2) pm. Die Struktur von 1h wird im Zusammenhang mit der Zunahme der Elektronendichte betrachtet und mit den Ergebnissen der Röntgenstrukturanalyse von CH3Si(NSN)3SiCH3 (2) verglichen. 2 kristallisiert kubisch (Raumgruppe P4132). Das bicyclische Molekül (S—N 150.4 (2), Si—N 173.7 (2)pm) hat praktisch D3h Symmetrie und zeigt keine S—S-Bindungen im Ring.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2339-2349 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Concerning the Question of Positional Isomerism in Disubstituted BullvalenesWe report about 15 new disubstituted bullvalenes (2, 4, 5, 11, 12, 14-20, 22-24) and discuss their substitution pattern together with 9 known species (1, 3, 6-10, 13, 21). The results which are partly unexpected are put together phenomenologically. We have no reasonable explanation for some results, i.e. only a few substituents with „complementary“ properties like the pair CH2OH/Br or CH3/CN in compounds 16 and 18, respectively, prefer a vicinal arrangement at a double bond.
    Notes: Wir berichten über 15 neue disubstituierte Bullvalene (2, 4, 5, 11, 12, 14-20, 22-24) und diskutieren ihr Substitutionsmuster gemeinsam mit dem von 9 bekannten Vertretern (1, 3, 6-10, 13, 21). Die teilweise unerwarteten Ergebnisse werden phänomenologisch geordnet. Für einige Befunde fehlen befriedigende Erklärungen. So bevorzugen z. B. nur manche Substituenten mit „komplementären“ Eigenschaften wie das Paar CH2OH/Br oder CH3/CN in den Verbindungen 16 bzw. 18 eine vicinale Anordnung an der Doppelbindung.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 113 (1980), S. 2221-2226 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Metabolites of Microorganisms, 195. The Structure of Ophiocordin, an Antibiotic with Antifungal ActivityThe structure of the antibiotic Ophiocordin (9), which exhibits antifungal activity, was elucidated by chemical degradation, mass spectrometry, and NMR. Ophiocordin contains a novel 3-amino-hexahydro-4-hydroxyazepin system (5), which is esterified with 4-hydroxybenzoic acid and connected to 3,3′,5′-trihydroxy-2,4′-carbonylbis[benzoic acid] (7) via an amide bond between the 1-carboxy group and the amino group of the azepin system.
    Notes: Die Konstitution des antifungisch wirksamen Antibiotikums Ophiocordin (9) konnte durch chemischen Abbau, Massenspektrometrie und Kernresonanz aufgeklärt werden. Ophiocordin enthält ein neuartiges 3-Aminohexahydro-4-hydroxyazepin-System (5), an das 4-Hydroxybenzoesäure esterartig und 3,3′,5′-Trihydroxy-2,4′-carbonylbis[benzoesäure] (7) über die Carboxylgruppe in 1-Stellung säureamidartig gebunden ist.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 515 (1984), S. 51-60 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of the Anion S3N3O2-, a Stable Six-membered Sulfur-Nitrogen Ring with an 8π-Electron SkeletonThe dark blue-violet cyclotrithiazene-dioxide anion S3N3O2-has been synthesized on different pathways: 1. reaction of S4N4O2 with alkali azides, 2. metathesis of (CH3)3ES3N3O2 (E = Si, Sn) with CsF, 3. addition of S4N4O2 and alkali bis(trimethylsilyl)-amides followed by cation exchange with tetraphenylarsonium chloride, and 4. reaction of S4N4O2 with trimethylsilyliminotriphenylphosphorane in a molar ratio of 1:1. Excess iminophosphorane leads to the formation of a covalent 1.5-disubstituted S4N4 derivative. Reaction mechanisms will be discussed and structures of trithiatriazine-anions will be compared.
    Notes: Das dunkelblauviolette Cyclotrithiatriazendioxid-Anion S3N3O2- konnte auf verschiedenen Wegen dargestellt werden: 1. Umsetzung von S4N4O2 mit Alkaliaziden, 2. Reaktion von (CH3)3ES3N3O2 (E = Si, Sn) mit CsF, 3. Addition von S4N4O2 und Alkali-bis(trimethylsilyl)-amiden mit anschließendem Kationenaustausch mit Tetraphenylarsoniumchlorid und 4. Umsetzung von S4N4O2 mit Trimethylsilyliminotriphenylphosphoran im Molverhältnis von 1:1. Ein überschuß des Iminophosphorans führt zur Bildung eines kovalenten 1,5-disubstituierten S4N4-Derivats. Reaktionsmechanismen werden diskutiert und Strukturvergleiche an Trithiatriazinanionen durchgeführt.
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  • 8
    ISSN: 0009-2940
    Keywords: Titanium-nitrogen bonds ; Dimer-monomer formation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Structures of Imidotitanium Compounds  -  Directing the Monomer-Dimer Formation by Changing the Basicity of the SolventsThe reaction of (i-Pr)2PN(SiMe3)2 (1) with elemental sulfur leads to (i-Pr)2P(S)N(SiMe3)2 (2). Compound 2 reacts with TiCl4 with elimination of chlorotrimethylsilane to yield the adducts [(i-Pr)2P(S)NTiCl2-MeCN]2 (3) and (i-Pr)2P(S)N = TiCl2.3py (4), crystallized from MeCN or pyridine, respectively. Compound 3 crystallises in the space group Pbca, 4 in the space group p&1macr;.
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  • 9
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and X-Ray Structure Analysis of the 8π-Electron-Ring-System S4N4O2Sn2(CH3)6 and the Magnetic Properties of S4N4O2 and S8N8O4S4N4O2 reacts with N[Sn(CH3)3]3 in a molar ratio of 1:1 to an eight-membered trimethyltin-substituted 8π-electron skeleton, S4N4O2Sn2(CH3)6. In contrast to known 6π-electronsystems this compound has tin atoms which are tetracoordinated. This was demonstrated on the basis of an x-ray analysis. S4N4O2Sn2(CH3)6 · 1/2 C6H6 crystallizes in the space group P21/c with a = 1396.0(4), b = 1190.3(4), c = 1256.7(3) pm, and β = 103.46(2)°. It was shown that the ability of coordination at the tin atom depends on the electron density. The magnetic properties of S4N4O2 and S8N8O4 were investigated by the Faraday method. The high diamagnetism in these ring compounds is caused by the π-electrons.
    Notes: S4N4O2 reagiert mit N[Sn(CH3)3]3 im Molverhältnis 1:1 zum achtgliedrigen trimethylzinnsubstituierten 8π-Elektronengerüst, S4N4O2Sn2(CH3)6. Im Gegensatz zu bekannten 6π-Elektronensystemen haben in dieser Verbindung die Zinnatome die Koordinationszahl 4. Dies konnte auf Grund einer Röntgenstrukturanalyse ermittelt werden. S4N4O2Sn2(CH3)6 · 1/2 C6H6 kristallisiert in der Raumgruppe P21/c mit a = 1396,0(4), b = 1190,3(4), c = 1256,7(3) pm und β = 103,46(2)°. Es wird gezeigt, daß die Koordinationsfähigkeit am Zinnatom von der Elektronendichte abhängig ist. Das magnetische Verhalten von S4N4O2 und S8N8O4 wurde nach der Faraday-Methode bestimmt. Der gefunden hohe Diamagnetismus in diesen Ringverbindungen wird durch die π-Elektronen verursacht.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 125 (1992), S. 825-831 
    ISSN: 0009-2940
    Keywords: Zirconium amides, imides ; Hafnium amides, imides ; Amides ; Imides ; ZrN double bond ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Structures of (Monoorganyl)amides and -imides of Zirconium and HafniumThe tetrahalides MCl4 (M = Zr 1 a, Hf 1 b) react with LiNHtBu with elimination of LiCl to yield [(tBuNH)2MNtBu]2 (3) (M = Zr 3a, Hf 3b). Compounds 3 are thermally instable and oli-gomerise above 100 °C with elimination of H2NtBu. The reactions of (η5-C5Me5)MCl3 (M = Zr 1 c, Hf 1 d) with LiNHR (R = tBu 2 a,2,4,6-Me3C6H2 2 b, 2, 6-iPr2C6H3 2 c) lead to (η5-C5Me5)M(NHR)3 (4) (R = tBu, M = Zr 4 a, Hf 4 b; R = 2, 4,6-Me3C6H2, M = Zr 4 c, Hf 4 d; R = 2,6-iPr2C6H3, M = Zr 4 e, Hf 4 f). Compounds 4 are thermally very stable and melt without decomposition. When 1 c and 1 d react with LiNHPh (2 d), dimers of composition [(η5-C5Me5)M(NHPh)NPh]2 (M = Zr 5 a, Hf 5 b) are obtained. The complexes (η5-C5Me5)2MCl2 (M = Zr 1 e, Hf 1 f) react with 2 b to form (η5-C5Me5)2M(NHR)2 (6) (M = Zr 6 a, Hf 6 b). Pyridine reacts with 4 e at 85 °C and replaces one molecule of 2,6-iPr2C6H3NH2 to give (η5-C5Me5)Zr-(NHR)NR · Py (7). The single crystal X-ray structures of 4 a, 4 f, 5 b and 7 are described.
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