Elimination of a-halosilanes: A mild approach to benzylic carbenes

by Allison, Neil T.; Loeschel, Christian M.

The generation of carbenes is usually done under either strongly basic conditions or through unstable and potentially explosive intermediates. Herein we report a study of carbenes from a-bromosilanes under mild conditions. Upon treatment of 1 with tetra-Bu ammonium fluoride at room temp., the corresponding dimer 2 is readily obsd. The mechanism of this dimerization reaction that is believed to proceed through a carbene intermediate will be presented. The scope and limitations of this method of generating carbenes will also be discussed.