A novel fiber-supported cooperative catalyst for the carboxylation of terminal alkynes through CO2 utilization

Abstract

Herein, a novel fiber-supported N-heterocyclic carbene (NHC) precursor and copper(I) composite (EIMBr-PANFTA@CuI), capable of acting as a cooperative catalyst for cleaner carboxylation of terminal alkynes from CO2, is presented. The EIMBr-PANFTA@CuI was synthesized systematically, and the resulting fiber samples from preparation and utilization processes were characterized detailedly. Moreover, the unique fiber-supported composite structure as a cooperative catalyst exhibited the synergistic effect on the activation of CO2 and terminal alkyne, which corporately contributed to the high catalytic performance on carboxylation for producing a series of alkyl 2-alkynoates in acetonitrile under ambient conditions. Furthermore, EIMBr-PANFTA@CuI was stable to air and moisture, and could be easily recovered with a tiny pair of tweezers and recycled with good activity over 10 runs. In addition, this protocol was convenient and effective for gram-scale experiments and thereby was prospective in practical applications.