Ag(I)-Catalyzed C–H Carboxylation of Thiophene Derivatives

Abstract

CO2 utilization is an attractive aspect as it allows the direct conversion of CO2 into valuable chemicals. In this regard, direct incorporation of CO2 into the C–H bond of heteroaromatic compounds is important due to the ubiquitous structural motifs of the heteroaromatic carboxylic acids. Herein, we report the Ag-catalyzed C–H carboxylation of thiophene derivatives. This new catalytic system involving a phosphine ligand and lithium tert-butoxide enables the direct carboxylation of thiophenes under mild reaction conditions. Experimental studies revealed that the use of tert-butyl alkoxide is critical for the exergonic formation of an arylsilver intermediate, and the results were further supported by density functional theory calculations.