2-(5-Methyl-7-nitro-1-indolinyl)benzoic acid → 4-Methyl-1,2-dihydrobenzo[c]pyrrolo[1,2,3-ef][1,5]benzodiazepin-7-one

Participants

Reaction Steps

To a solution of 2-(5-methyl-7-nitroindolin-1-yl)benzoic acid (9 g, 0.03 mole), conc. hydrochloric acid (several drops) and ethanol (200 ml) was added 5% palladium-charcoal (1.5 gm). The mixture was shaked under hydrogen (58 psi) for 30 hours. The solvent was removed and the residue was loaded onto a silica gel flash chromatography column (800 g, 230-400 mesh), packed and eluted with dichloromethane (4 l) and 2% methanol in dichloromethane (4 l). The fractions containing product were pooled and evaporated to yield 5 g (66%) of product. Recrystallization from chloroform gave the analytical sample, mp 222°-224° C.

Provenance & Evidence