Novel synthetic strategy of carbolines via palladium-catalyzed amination and arylation reaction

Four parent carbolines and the corresponding 5- or 9-methylsulfonyl derivat ives were synthesized by the palladium-catalyzed intramolecular arylation r eaction of ortho-bromo-substituted anilinopyridines which were prepared by the palladium-catalyzed arnination reaction of iodobenzenes with aminopyrid ines. Carbazole and its 9-methylsulfonyl derivative were also synthesized b y the same method.