Facile synthesis of enol ethers via Zn(OTf)2-mediated formal alkyne hydration-Smiles rearrangement

Abstract

An efficient protocol involving commercially available zinc trifluoromethanesulfonate was able to transform a terminal alkyne to an enol ether via a formal tandem Markovnikov hydration-Smiles type rearrangement. The chemoselective reaction was able to work with a range of heteroaromatic tethers such as diazine, pyridine, benzimidazole and benzothiazole.