Cyclisierungsreaktionen von Diazoalkenyl-phosphonsäureestern Synthese von Pyrazolyl- und 2,3-Benzodiazepinylphosphonsäureestern

Tosylhydrazones3 and4 of dialkyl 3-oxo-1-alkenylphosphonates1 and 1-oxo-2-alkenylphosphonates2, respectively, react with aqueous sodium carbonate to give the pyrazoles7 in excellent yields. Under analogous conditions the tosylhydrazone9 of diethylo-vinylbenzoyl phosphonate (8) affords diethyl 2-hydroxy-1-indanyl phosphonate (10). Upon thermolysis of the sodium salt12 generated from9 in anhydrousD M E, one obtains, depending on the reaction conditions, either the 1-H-benzodiazepinyl derivative14 or its 5H-isomer15. At room temperature the diazo compound13 cyclizes slowly to give14, which can be isomerized to15 by action of base.

     

Synthese und Eigenschaften von 6-Desoxy-6-halogen-Derivaten der L-Ascorbinsäure

Synthesis and Properties of 6-Deoxy-6-halogeno-Derivatives of L -Ascorbic Acid 6-Deoxy-6-chloro-, -6-bromo-, -6-iodo- and -6-fluoro derivatives of L -ascorbic acid have been synthesized and characterized. The physiological properties of the chloro derivative have been investigated. It shows a high antiscurvy activity. The chloro- and bromo-derivatives have been reduced to the corresponding deoxy compound, which is an interesting chiral intermediate for the preparation of rare ω-deoxy sugars.     

Synthese und Eigenschaften von neuen aromatischen-aliphatischen Copolyimiden

Ohne Zusammenfassung     

Synthese,Eigenschaften und Kristallstrukturen von Magnesium-Diazadien-Komplexen

Synthesis, Properties and Crystal Structures of Magnesium Diazadiene Complexes Reactions of phenyl-substituted 1,4-diaza-1,3-butadienes (DAD) RN?CPh? CPh?NR (R = C₆H₅) 1a , C₆H₄-4-CH₃ 1b , C₆H₄-4-OCH₃ ( 1c ) with magnesium in dimethoxyethan lead to complexes of the type [Mg(DAD)₂(DME)] 2a–c , with DAD ligands in form of radical anions. Furthermore, highly reactiv complexes of the composition [Mg(DAD)(DME)₂] 3a–c could be obtained. The crystal structures of 2a, 3a and 3c were determined.     

Synthese und Eigenschaften der Furo- und Thieno-Analogen von PQQ-Triester

Synthesis and Characterization of the Furo and Thieno Analogues of the Triester of PQQ We report here the synthesis and properties of the furo and thieno analogues of 4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f]quinoline-2,7,9- tricarboxylic acid ( = PQQ), i.e. the furo- and thieno[2,3-f]quinoline-4,5-quinone (FQQ and TQQ, resp.) derivatives B and C , obtained as triesters. The triester of PQQ derivative A is much more stable than the triesters of B or C , and only the triester of A shows strong activity in nonenzymatic catalytic oxidations.     

Synthese und Eigenschaften von Dimolybdän-μ-nitrido-heptachlorid Mo2NCl7

Synthesis and Properties of Di-molybdenum-μ-nitrido-heptachloride, Mo₂NCl₇ Mo₂NCl₇ was prepared by the reaction of molybdenum pentachloride with the bromide of Millon's base, [Hg₂N]Br, in boiling CCl₄. It forms a moisture sensitive, dark green crystal powder, the magnetic moment at 20°C (μ_eff = 0.95 B.M.) being strongly reduced. With acetonitrile the μ-nitrido complex Mo₂NCl₇ · 3CH₃CN is formed, with phosphoryl chloride the donor acceptor complex Mo₂NCl₇ · 2POCl₃, respectively. Partial oxidation of the latter complex with chlorine leads to very unstable Mo₂NCl₈ · 2POCl₃, from which (PPh₄)₃[Mo₃NCl₁₀] can be obtained by the reaction with PPh₄Cl. For the complex (PPh₄)₃[Mo₂NCl₁₀] is also found a reduced paramagnetism of μ_eff = 1.47 B.M. at 20°C. All complexes are characterized by i.r. spectroscopy.     

Synthese von Arsensäureestern

Zusammenfassung Es wird die Umsetzung von Benzylhalogeniden und substituierten Benzylhalogeniden mit Ag₃AsO₄, AgH₂AsO₄, Ag₂HAsO₄ und PbHAsO₄ beschrieben. Im Zuge dieser Arbeit wurden der Arsensäuretribenzylester, der Arsensäure-tri-p-chlorbenzylester und der Arsensäuretri-p-brombenzylester erstmalig dargestellt.

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The reaction of benzyl halides and substituted benzyl halides with Ag₃AsO₄, AgH₂AsO₄, Ag₂HAsO₄ and PbHAsO₄ is described. Tribenzyl, tri-p-chlorobenzyl and tri-p-bromobenzyl arsenate were prepared for the first time.

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Herrn Prof. Dr.E. Philippi zum 80. Geburtstag gewidmet.