Identification of the Stereoisomers of 1,2,3,4-tetramethyl-1,2,3,4-tetraphenylcyclotetrasilanes.

摘要

The configuration of three synthetically available stereoisomers (tttt, ttcc, and tctc) of 1,2,3,4-tetramethyl-1,2,3,4-tetraphenylcyclotetrasilane have been unambiguously assigned using spin labeling techniques and by preparing chemical derivatives. 1JC-Si, 2JC-Si, and 3JC-Si values were determined for the three stereoisomers with 13C labeled methyl groups. The dominating isomer resulting from the synthesis possesses an all-trans structure and can be isolated in up to 95% purity.