Ambient Intermolecular [2 + 2] Cycloaddition: An Example of Carbophilicity and Oxophilicity Competition in Au/Ag Catalysis

Abstract

The gold-catalyzed intermolecular [2 + 2] cycloaddition of propargyl esters was achieved with good stereoselectivity. The “silver-free” condition was critical for this transformation, while only a trace amount of [2 + 2] products were formed in the presence of silver under otherwise identical conditions