The reaction of tert-butyldiphenylsilylcuprates with allenes

Abstract
Bis(tert-butyldiphenylsilyl)cuprate 1 reacts with allenes to form allyl- and vinyl-silanes. With allene itself the cuprate reagent shows a different regiochemistry from that of bis(phenyldimethylsilyl)cuprate. The regiochemistry can be controlled by choosing an appropriate reaction temperature. The intermediate cuprate 4 resulting from the addition of 1 to allene reacts with a wide variety of electrophiles giving functionalised allylsilanes. Phenylallenes isomerise to acetylenes.