Domino Reaction of Isatins with α‐Oxoketene‐N,S‐acetals: An Efficient Synthesis of Pyrrolo[3,4‐c]quinoline‐1,3‐diones and 2,3‐Dihydro‐1H‐pyrrolo[3,4‐c]quinolin‐1‐ones

Abstract

A straightforward synthesis of pyrrolo[3,4-c] quinoline-1,3-diones and 2,3-dihydro-1H-pyrrolo[3,4-c] quinolin-1-ones has been accomplished by the cascade reaction of isatins with α-oxoketene-N,S-acetals using BF 3 • Et 2 O in DMSO/toluene at 110 °C. The reaction offers an easy access to biologically important tricyclic N-heterocycles via CÀ C/CÀ X bond formation.