Efficient copper catalysts for C[sbnd]H bond arylation under microwave heating: Direct access to multi-substituted pivanilides

Abstract

We herein describe a parallel comparison between homogeneous and heterogeneous copper catalysts for microwave-assisted direct C[sbnd]H bond arylation. These catalytic systems feature enhanced catalytic activities, unique bulky ligand/base effects, mild conditions, and operational simplicity with reduced catalyst loadings and shortened reaction times. A wide range of synthetically challenging multi-substituted pivanilides was directly assembled. Remarkably, copper-exchanged beta-zeolite under ligand-free condition shows good recyclability demonstrating its potential as an efficient and reusable heterogeneous catalytic platform. © 2016 Elsevier B.V