Trifluoroacetic acid → HCID 89783902, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl 2-(3-(benzyloxy)-1-((tert-butoxycarbonyl)amino)propyl)-5-(3-(tert-butylamino)-2-methylquinoxalin-5-yl)-1H-pyrrole-3-carboxylate (1.28 g, 1.98 mmol) in 20 mL of DCM at RT was added TFA (5 mL) and the dark red solution was heated in an oil bath at 40° C. for 4 h. It was concentrated under reduced pressure. 5 mL of toluene was added to the residue and concentrated to dryness again. The brown amorphous solid was stirred in 15 mL of hexanes and the liquid was decanted. The brown residue was treated with 5 mL of DMF and 30 mL of DCM, cooled at 0° C., and added DIPEA (2.06 mL, 11.88 mmol) followed by (benzotriazol-1-yloxy)tripyrrolidinophosphonium hexafluorophosphate (1.28 g, 2.47 mmol). It was stirred at 0° C. for 10 min followed by RT for 15 min, then diluted with 50 mL of DCM. The mixture was washed sequentially with 5 mL of water, 5 mL of 0.5 N NaOH, and 5 mL of brine. The DCM solution was concentrated. The residue was purified on a silica gel column (50-100% EtOAc in DCM followed by 5% MeOH in DCM) to give 6-(2-(benzyloxy)ethyl)-2-(3-(tert-butylamino)-2-methylquinoxalin-5-yl)-5,6-dihydropyrrolo[3,4-b]pyrrol-4(1H)-one (0.65 g, 1.38 mmol, 70% yield) as a brown crystalline solid. m/z (ESI, +ve) 470.0 (M+H)+.

Provenance & Evidence