Structure of an η¹ Nickel <i>O</i>-Enolate:  Mechanistic Implications in Catalytic Enyne Cyclizations

Abstract

Two metallacycles derived from the oxidative cyclization of nickel(0) with an alkynyl enal have been isolated and fully characterized. The metallacycles obtained possess an η 1 nickel O -enolate motif within the metallacyclic framework.