Unexpected cycloisomerizations of nonclassical carbocation intermediates in gold(I)-catalyzed homo-rautenstrauch cyclizations

摘要

An unexpected gold(I)-catalyzed homo-Rautenstrauch rearrangement of 1-cyclopropyl propargylic esters to cyclohexenones is disclosed. This rearrangement represents new evidence for the recently discussed gold-stabilized nonclassical carbocation character of intermediates in gold catalysis. A mechanistic study proved partial chirality transfer from optically active propargyl acetates.