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Developing an efficient catalytic system using molecular oxygen as the oxidant for rhodium-catalyzed cross-dehydrogenative coupling remains highly desirable. Herein, rhodium-catalyzed oxidative annulation of 2- or 7-phenyl-1<i>H</i>-indoles with alkenes or alkynes to assemble valuable 6<i>H</i>-isoindolo[2,1-<i>a</i>]indoles, pyrrolo[3,2,1-<i>de</i>]phenanthridines, or indolo[2,1-<i>a</i>]isoquinolines using the atmospheric pressure of air as the sole oxidant enabled by quaternary ammonium salt has been accomplished. Mechanistic studies provided evidence for the fast intramolecular aza-Michael reaction and aerobic reoxidation of Rh(I)/Rh(III), facilitated by the addition of quaternary ammonium salt.