Enantioselective Propargylic C(sp³)-H Acyloxylation Enabled by Photoexcited Copper Catalysis

Direct C-H bond functionalization is an efficient method for modifying organic molecules. However, achieving high enantioselectivity and regioselectivity in asymmetric C-H functionalization, particularly of C(sp³)-H bonds, remains challenging. This study introduces an enantioselective propargylic C(sp³)-H acyloxylation using photoexcited copper catalysis. The reaction demonstrated tolerance for various alkynes and peroxides, producing chiral propargyl esters in high yields and enantiomeric excess. Furthermore, the method was successfully extended to a diverse array of carboxylic acids in the presence of di-tert-butyl peroxide (DTBP), significantly broadening its applicability.