DMAP-stabilized bis(silyl)silylenes as versatile synthons for organosilicon compounds.

DMAP-stabilized silylenes 1a-c are obtained from the reductive debromination of the corresponding dibromosilanes in the presence of DMAP. Their distinctly different thermal isomerization reactions via C-H bond activation, dearomative ring expansion and silyl migration are discussed. Furthermore, complexes 1 dissociate at elevated temperatures, providing the corresponding free silylenes in situ , which are even capable of single-site activation of H 2 . Additionally, a potassium-substituted silicon-centered radical 2 is isolated from overreduction of ( t Bu 3 Si) 2 SiBr 2 .