Cationic Gold(<scp>I</scp>) Complexes: Highly Alkynophilic Catalysts for the <i>exo</i>‐ and <i>endo</i>‐Cyclization of Enynes

Abstract

As good as gold: Alkynophilic cationic gold(I) complexes are very active catalysts for reactions of enynes that proceed exclusively through cyclopropyl carbene complexes as intermediates (see scheme). With such catalysts, the first examples of endocyclic skeletal rearrangements under mild conditions have been observed.