CARBOXYLATION MADE SIMPLE

Abstract

A STRAIGHTFORWARD and environmentally friendly technique uses carbon dioxide to convert acidic C—H bonds in aromatic compounds into acid and ester groups. The reaction could make aromatic acids and esters more readily available for use in organic synthesis, drug discovery, and other applications. The reaction uses N-heterocyclic carbene (NHC) gold(I) catalysts, which are stable and recyclable and require no special handling. It was developed by postdoctoral fellow Ine I. F. Boogaerts and chemistry professor Steven P. Nolan of the University of St. Andrews, in the U.K. ( J. Am. Chem. Soc., DOI: 10.1021/ja103429q). Unlike existing ways to carboxylate aromatic C—H bonds, the reaction proceeds at room temperature and moderate pressure, and its only by-product is water. “This is probably the first example of taking an unactivated C—H bond and directly converting it into a carboxylic acid group,” comments Tomislav Rovis of Colorado State University, a specialist in NHC and transition-metal catalysis. “It’s surp...