Pd(II)-catalyzed C-H activation/aryl-aryl coupling of phenol esters

J Am Chem Soc. 2010 Jan 20;132(2):468-9. doi: 10.1021/ja909818n.

Abstract

Although nitrogen-containing group-directed cyclopalladation reactions have been well-known, Pd(II) insertion into C-H bonds promoted by coordination of an oxygen-only group to the palladium remains rather rare. In the present study, the first cyclopalladation complex formed from a simple phenol ester was characterized by X-ray crystallography. A promising protocol for the ortho C-H activation/aryl-aryl coupling of phenol esters that was not sensitive to moisture or air was then established. The utility of the reaction was demonstrated for the synthesis of useful phenol derivatives.