A general, versatile synthesis of 2H-pyrrolo(3,4-c)quinolines via tosylmethylisocyanide reaction

A new synthetic procedure for obtaining 2H-pyrrolo(3,4-c)quinolines is reported. The synthetic pathway utilizes TosMIC reaction to prepare appropriate nitroarylpyrrylcarboxylic esters, which on treatment with Fe-AcOH undergo reduction of nitro group with concomitant intramolecular cyclization to give title derivatives. The procedure proved general and more profitable than those previously reported in the literature. The synthesis of still unknown parent compound 4 via TosMIC is described. 2H-Pyrrolo(3,4-c)quinolines substituted at 1 and 3 positions have been obtained by making use of methyl-TosMIC.