We report a simple method for copper-catalyzed benzylic C–H alkynylation that uses alkynylboronic esters as nucleophilic coupling partners. The catalytic system is readily available and the reaction takes place under mild conditions. Different substrates for the C–H functionalization, as well as various alkynylboronic ester nucleophiles, were evaluated. Finally, three examples of enantioselective C–H alkynylations are presented.
Bibliographical noteS.K. is deeply appreciative of financial support from the Lundbeck Foundation (grant no. R250-2017-1292), the Independent Research Fund Denmark (grant no. 0171-00018B), and the Villum Foundation (grant no. 35812). Z.L. thanks the National Natural Science Foundation of China (21901168), the ‘1000-Youth Talents Plan’, Sichuan Science and Technology Program (2021YJ0395), and Sichuan University for generous financial support.
- C–H functionalization
- copper catalysis
- homogeneous catalysis
- boronic esters