beta-Trimethyisilyl allenes have been prepared in fair to good yields
from allylsilanes by successive dibromocarbene addition and rearrangem
ent of the cyclopropylidenes. In the case of 3,6-bis(trimethylsilyl)cy
clohexa-1,4-diene, insertion of dibromocarbene occurs in the silicon-c
arbon bond leading to alpha-bromobenzyltrimethylsilane. (C) 1997 Publi
shed by Elsevier Science Ltd.