Racemic total synthesis of oxomaritidine by iodobenzene-catalyzed oxidative phenolic coupling under mild reaction conditions

A hypervalent iodine-catalyzed phenolic coupling reaction of norbelladine derivatives was examined with a catalytic amount of iodobenzene and meta-chloroperbenzoic acid as the terminal oxidant. The addition of acetic acid dramatically accelerated the reaction rate even at room temperature, and the cyclized products were successfully obtained under mild reaction conditions. The methods were applicable to the racemic total synthesis of oxomaritidine.