Synthesis of Carbalexin B, Clausine A, Clauszoline M, and 2,8-Dihydroxy-3-methylcarbazole

Using a palladium(II)-catalyzed oxidative cyclization of an N , N -diarylamine, we have achieved the total synthesis of the 2,8-dioxygenated carbazole alkaloids carbalexin B, clausine A, clauszoline M, and 2,8-dihydroxy-3-methylcarbazole.