Chan-Evans-Lam Cu(II)-Catalyzed C–O Cross-Couplings: Broadening Synthetic Access to Functionalized Vinylic Ethers

We report a general
and effective Cu(OAc)2-catalyzed
C–O cross-coupling synthesis of di- and trisubstituted vinylic
ethers, using a combination of N-isopropylimidazole
ligand and dicumyl peroxide as stoichiometric oxidant. This method
couples functionalized vinylic pinacolboronates with various 1°
and 2° alcohols to provide single-step syntheses of novel and
structurally complex vinylic ethers. The optimized conditions do not
require excess alcohol reactant and substantially suppress competing
side reactions.