Cu(I)/Pd(II)-Catalyzed Intramolecular Hydroamidation and C-H Dehydrogenative Coupling of ortho-Alkynyl-N-arylbenzamides for Access to Isoindolo[2,1-a]Indol-6-Ones

An efficient, atom-economic and one-pot synthesis of isoindolo[2,1-a]indol-6-ones via CuI/Pd(OAc)(2)-catalyzed intramolecular hydroamidation of alkynyl group, and C-H dehydrogenative coupling of ortho-alkynyl-N-arylbenzamides has been developed. This transformation occurs with the use of oxygen as the oxidant, and water is the only by-product. The reaction shows a high tolerance to a variety of functional groups, and affords isoindolo[2,1-a]indol-6-ones in good to high yields.