One-pot tandem synthesis of carbazole-1,4-quinone from Fischer-Borsche ring using molecular iodine/periodic acid

An efficient method for the synthesis of carbazole-1,4-quinones has been achieved from the Fischer-Borsche ring using a combination of a catalytic amount of molecular iodine and periodic acid. The developed protocol displayed a broad range of substrate scope and good tolerance to a variety of substituents. The key step of the develop protocol involved double-oxidation of Fischer-Borsche ring. Moreover, the effectiveness of this method has been extended to the concise synthesis of bioactive Murrayaquinone A and Koeniginequinone A.