Golden carousel in catalysis: The cationic gold/propargylic ester cycle

Abstract

(Figure Presented) Round and round it goes: Propargylic esters are versatile substrates for Au-based catalysts. However, under typical conditions the starting Au-coordinated propargylic ester 1 is in rapid equilibrium with the gold vinylic carbenoid species 2 and with gold allene species 3. A number of factors dictate which intermediate is lower in energy and which type of products form. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.