Rh-catalyzed [3+3]-annulation of quinolines with cyclopropenones: access to functionalized 2-quinolones

Abstract

Rh-catalyzed weak-directing-group-facilitated sequential C–H/C–C functionalization of quinoline N-oxides with cyclopropenones has been accomplished to furnish functionalized 2-quinolones. The reaction sequence involves a cascade C–C/C–N bond formation and oxygen atom transfer from water. The substrate scope, functional group tolerance and H₂O¹⁸ labelling experiment are the important practical features.