Organosilicon chalcogenides with trisilane units – bicyclo[3.3.1]nonanes, bicyclo[3.2.2]nonanes and spiro[4.4]nonanes

Abstract

Treatment of 1,2,3-trichloropentamethyltrisilane ( 1) with H 2S/NEt 3 results in the formation of a mixture of two isomers of (Me 5Si 3) 2S 3 with a bicyclo[3.3.1]nonane ( 2a) and a bicyclo[3.2.2]nonane ( 2b) skeleton, while the reaction of 1 with Li 2Se yields one product only, (Me 5Si 3) 2Se 3 ( 3a), with a bicyclo[3.3.1]nonane structure. Besides 1H, 13C, 29Si and 77Se NMR spectroscopy 3a has also been characterized by a crystal structure analysis. Compounds Si(SiMe 2EMR 2E) 2 ( 5a– h: MR 2: SiMe 2 ( 5a, c, d), SiPh 2 ( 5b), GeMe 2 ( 5e, f), SnMe 2 ( 5g, h); E=S ( 5a, b, e, g), Se ( 5c, f, h), Te ( 5d)) with a spiro[4.4]nonane skeleton have been obtained in mixture with varying amounts of the corresponding six-membered rings (R 2ME) 3 by reactions of mixtures of 1,2,2,3-tetrachlorotetramethyltrisilane ( 4) and diorganodichlorosilanes, Me 2GeCl 2 or Me 2SnCl 2, with H 2S/NEt 3, Li 2Se or Li 2Te and have been characterized in situ by multinuclear NMR spectroscopy ( 1H, 13C, 29Si, 119Sn, 77Se, 125Te) and GC-MS.