Copper-catalyzed oxidative coupling of arylboronic acids with aryl carboxylic acids: Cu3(BTC)2 MOF as a sustainable catalyst to access aryl esters

Abstract

A convenient and sustainable method is demonstrated for the oxidative coupling of arylboronic acids with aryl carboxylic acids via C–O cross-coupling reaction catalyzed by the unsaturated coordination sites of copper present in the Cu₃(BTC)₂ MOF. Using air as an environment-friendly oxidant, the as-prepared Cu₃(BTC)₂ was employed in a MOF-based catalysis reaction with high efficiency and high chemoselectivity without the use of any external oxidants, ligands or additives. The present methodology avoids stoichiometric reagents and special reaction conditions, and shows excellent functional group tolerance with decent to excellent yields of aryl esters. The catalyst was found to exhibit high stability and reusability, without loss in activity even after several cycles, which was evident from the FT-IR, PXRD, and SEM characterizations of the reused catalyst.