Insight into the palladium-catalyzed oxidative arylation of benzofuran: Heteropoly acid oxidants evoke a Pd(II)/Pd(IV) mechanism

Kyle C. Pereira, University of Rhode Island
Ashley L. Porter, University of Rhode Island
Shathaverdhan Potavathri, University of Rhode Island
Alexis P. Lebris, University of Rhode Island
Brenton Deboef, University of Rhode Island

Abstract

The effects of oxidant and organic acid additives on the oxidative cross-coupling reactions of electron rich heterocycles, such as benzofuran with benzene were studied. Both regioselectivity and reaction rate could be controlled by varying the condition parameters. Furthermore, mechanistic insight was achieved via kinetic studies, which indicate that reactions that are oxidized by the heteropoly acid H4PMo11VO40 operate via a Pd(II)/Pd(IV) mechanisms, while reactions oxidized by either AgOAc or Cu(OAc)2 operate by a Pd(II)/Pd(0) mechanism.© 2012 Elsevier Ltd. All rights reserved.