First example of regiospecific intermolecular C-H insertion reactions of cyclic rhodium carbenoids: novel synthesis of 3-indol-3 '-yloxindoles

Facile regiospecific intermolecular C-H insertion reactions of cyclic rhodium carbenoids have been achieved using diazo carbonyl compounds 1 and indole or N-substituted indoles to afford 1,3-dihydro-1'H-[3,3]biindolyl-2-ones, 3a-o in an excellent yield.