Expedient synthesis of pyrroloquinolinones by Rh-catalyzed annulation of n -carbamoyl indolines with alkynes through a directed C-H functionalization/C-N cleavage sequence

A Rh-catalyzed redox-neutral C-H functionalization of N-carbamoyl indolines with various internal alkynes has been developed. The reaction, which involves the sequential cleavage of the C-H bond of the indoline at the C7-position and the C-N bond of the urea motif, provides a divergent protocol to rapidly assemble fused-ring pyrroloquinolinone analogues by using a direct alkenylation/annulation strategy with high efficiency and selectivity.