Copper(II)-Mediated O-Arylation of Protected Serines and Threonines

An effective protocol toward the O-arylation of beta-hydroxy-alpha-amino acid substrates serine and threonine has been developed via Chan-Lam cross-coupling. This Cu(II)-catalyzed transformation involves benign open-flask conditions that are well-tolerated with a variety of protected (Boc., Cbz-, Tr-, and Fmoc-) serine and threonine derivatives and various potassium organotrifluoroborates and boronic acids.