- Access to Cyclic Borates by Cu-Catalyzed Borylation of Unactivated Vinylcyclopropanes
Zhang, C.; Mazet, C.
Org. Lett. 2024, 26, 5386-5390
We report the copper-catalyzed borylation of unactivated vinylcyclopropanes to form six-membered cyclic borate salts. A copper complex bearing an N-heterocyclic ligand in combination with bis(pinacolato)diboron and LiOtBu catalyzes the ring-opening of the substrate under mild reaction conditions. The protocol can be applied to aryl- and heteroaryl-substituted vinylcyclopropanes and can be conducted on a gram scale. The synthetic utility of the lithium salts of the cyclic borate has been demonstrated through regioselective ring-opening functionalizations.