Gold(I)-Catalyzed Reactions between <i>N</i>-(<i>o</i>-Alkynylphenyl)imines and Vinyldiazo Ketones to Form 3-(Furan-2-ylmethyl)-1<i>H</i>-indoles via Postulated Azallyl Gold and Allylic Cation Intermediates

Abstract

This work describes gold-catalyzed additions of vinyldiazo ketones to <i>N</i>-(<i>o</i>-alkynylphenyl)imines to yield 3-(furan-2-ylmethyl)-1<i>H</i>-indoles involving skeletal rearrangement; these new catalytic reactions are applicable to a wide range of substrates. We postulate a new mechanism involving an initial addition of diazo ketones to azomethine ylide intermediates to yield gold-containing <i>N</i>-alkylated indole intermediates that undergo proton-induced 1,3-group migrations, generating azallyl gold and allylic cation pairs.