Gold(i)-catalyzed addition of carboxylic acids to internal alkynes in aqueous medium

Org Biomol Chem. 2017 Feb 21;15(7):1670-1679. doi: 10.1039/c6ob02800d. Epub 2017 Jan 27.

Abstract

We report herein the efficient hydro-oxycarbonylation of symmetrical and unsymmetrical internal alkynes with carboxylic acids in water at 60 °C, employing the catalytic system [AuCl(PPh3)]/AgOAc (5 mol%). This simple and eco-friendly protocol allows for the synthesis of a wide variety of trisubstituted enol esters (37 examples) in high yields and with complete Z-stereoselectivity. The use of microwave irradiation as an alternative energy source has also been evaluated.