Water-initiated hydrocarboxylation of terminal alkynes with CO2 and hydrosilane

Abstract

This work discloses a Cu(II)–Ni(II) catalyzed tandem hydrocarboxylation of alkynes with polysilylformate formed from CO₂ and polymethylhydrosiloxane that affords α,β-unsaturated carboxylic acids with up to 93% yield. Mechanistic studies indicate that polysilylformate functions as a source of CO and polysilanol. Besides, a catalytic amount of water is found to be critical to the reaction, which hydrolyzes polysilylformate to formic acid that induces the formation of Ni–H active species, thereby initiating the catalytic cycle.