Gold-catalyzed transesterification of ortho-alkynylbenzoic acid esters: a novel protecting group for alcohols and phenols
Treatment of ortho-alkynylbenzoic acid esters with excess amounts of EtOH in the presence of a gold catalyst results in the liberation of alcohols or phenols in high yields under mild conditions. The protection of alcohols and phenols proceeds smoothly by use of ortho-alkynylbenzoic acid or ortho-iodobenzoyl chloride. Highly chemoselective deprotections are described.