Coupling phenols and allylic alcohols

Abstract

Although chemists have plenty of ways to add carbon atoms to alkenes—including the Nobel Prize-winning Heck reaction—they have fewer options when working with heteroatom nucleophiles, such as alcohols. Now, Matthew S. Sigman and his group at the University of Utah report an intermolecular oxa-Heck reaction that allows them to couple phenols with allylic alcohols in an enantioselective manner (J. Am. Chem. Soc. 2016, DOI: 10.1021/jacs.6b11486). The reaction, which is catalyzed by palladium in the presence of a chiral pyridine oxazoline ligand, creates building blocks that would be tough to make using more common synthetic reactions, such as a Michael addition (example shown). Sigman’s team selected allylic alcohols as the alkene in the reaction in order to influence which hydrogen would be removed during the β-elimination to form the chiral product. The chemists show the reaction works with a broad scope of allylic alcohols and phenols, and even successfully swaps the