Cu(OAc)<sub>2</sub>-Promoted Oxidative Cross-Dehydrogenative Coupling Reaction of α-Acylmethyl Malonates with Indole Derivatives to Access 3-Functionalized Indoles and Polycyclic Indoles
A Cu(OAc)2-promoted oxidative cross-dehydrogenative coupling reaction of α-acylmethyl malonates with indole derivatives was developed. In the case of indoles, the regioselective coupling products were formed through a sequential dehydrogenation–addition–dehydrogenation process. When a second nucleophilic center was located in the 2-position of indoles, further successive nucleophilic cyclization occurred