Synthese,Struktur und Reaktivität eines 2,4-Diphosphino-1,3-diphospha-2,4-disilacyclobutans

Synthesis, Structure, and Reactivity of a 1,3-Diphosphino-2,4-diphospha-1,3-disilacyclobutane Pentamethylcyclopentadienyltrichlorosilane reacts with Li[Al(PH₂)₄] to give the stable 1,3-diphosphino-2,4-diphospha-1,3-disilacyclobutane 4 . Treatment of 4 with Lithium alkyls affords the Lithium phosphide 5 via regiospecific metalation of a ring phosphorus atom, and reaction with t-Bu₂Hg proceeds via oxidative P? P bond formation to yield the 1,4-disila-2,3,5,6-tetraphospha-bicyclo[2,1,1]-hexane 6 . Cleavage of pentamethylcyclopentadiene is observed during thermolysis of 4 at 200°C. 4–6 were characterised by NMR-spectroscopy, and 4 by an additional crystal structure determination.     

Synthese und ungewöhnliche Reaktivität eines Cyclotrisilans

Reductive coupling of dichlorosilane 1 with magnesium yields the stable, highly moisture sensitive cyclotrisilane 2a. The hydrolysis products, 1,3-siloxanediol 3 and disilane 4 corroborate the proposed structure of 2a. The reaction with typical silylene trapping agents like benzyl, benzophenone or 2,2′-bipyridyl results in cleavage of all three endocyclic bonds of 2a, yielding the formal silylene addition products 8, 9 and 10.     

Synthese und Charakterisierung von 1,3-dithia-2-boryl-[3]ferrocenophanen

The 1,3-dithia-2-boryl[3]ferrocenophanes (I-VIII) are obtained from the reaction of ferrocene-1,1′-dithiol (A) with dihalogenorganylboranes by elimination of the hydrogenhalides. I-VIII can be also prepared by starting from Fe(C₅H₄SLi)₂ · 2THF (B) inplace of A, but in lower yields. The air-sensitive [3] ferrocenophanes have been characterized analytically and spectroscopically (MS; NMR: ¹H, ¹¹B, ¹³C).     

Silylen-Reaktionen mit Selenophen und einem Tellurophen: Bildung und Strukturen eines 1,3-Diselena-2,4-disiletans und eines 1,3-Ditellura-2,4-disiletans [1]

Silylene Reactions with Selenophene and a Tellurophene: Formation and Structures of a 1,3-Diselena-2,4-disiletane and a 1,3-Ditellura-2,4-disiletane [1] Di-tert-butylsilylene, generated by photolysis of hexa-tert-butylcyclotrisilane, reacts with selenophene or 2,5-dimethyltellurophene by chalcogen abstraction to furnish the 1,3-diselena-2,4-disiletane 6 and 1,3-ditellura-2,4-disiletane 7 ring systems. The X-ray structure analyses of 6 and 7 reveal strictly planar four-membered rings with the smaller endocyclic angles at the chalcogen and the larger angles at the silicon atoms.     

Synthese,Charakterisierung und Magnetische Eigenschaften eines tetranuklearen,Thiacalix[4]aren‐stabilisierten Mangankomplexes

Synthesis, Characterization and Magnetic Properties of a Tetranuclear, Thiacalix[4]aren stabilized Manganese Complex Synthesis, characterization and magnetic properties of the compound [(TCA)(TCAH)Mn₄(acac)] ( 1 ) are reported, the first tetranuclear thiacalix[4]aren stabilized manganese complex synthesized under conventional conditions.