Lewis acid-assisted oxidative cross-coupling of 2-naphthol derivatives with copper catalysts

The oxidative coupling reactions between 2-naphthol and 3-hydroxy-2-naphthoic acid derivatives using a copper catalyst under an O2 atmosphere in the presence of a catalytic amount of the Lewis acid, such as Yb(OTf)3, were carried out. A highly cross-coupling selective or specific reaction effectively proceeded to give a C1 symmetrical BINOL derivative.