Hydrochloric Acid → methyl 2-(1-benzyl-4-(4-chlorophenyl)-6-methyl-7-oxo-6,7-dihydro-1H-pyrrolo[2,3-c]pyridin-5-yl)acetate

Participants

Reaction Conditions

Reaction Steps

A suspension of 2-(1-benzyl-4-(4-chlorophenyl)-6-methyl-7-oxo-6,7-dihydro-1H-pyrrolo[2,3-c]pyridin-5-yl)acetonitrile (3 g, 7.04 mmol) in Ethanol (60 mL) and Water (20 mL) was treated with KOH (3.95 g, 70.4 mmol) and then heated to 140° C. in a sealed tube for 24 hours. The mixture was cooled to 0° C. and then treated with 4N HCl until pH<2. The mixture was partly concentrated and then extracted with Ethyl acetate. The combined extracts were washed with brine, dried over sodium sulfate, filtered and then concentrated. The residue was dissolved in Methanol (60.0 mL), cooled to 0° C. and then treated with TMS-diazomethane (35.2 mL, 70.4 mmol). The mixture was warmed to ambient temperature and then stirred for 20 minutes. Upon reaction completion, the mixture was cooled to 0° C., quenched with acetic acid and then concentrated. The residue was purified on silica gel (0-70% ethyl acetate/hexanes) to afford methyl 2-(1-benzyl-4-(4-chlorophenyl)-6-methyl-7-oxo-6,7-dihydro-1H-pyrrolo[2,3-c]pyridin-5-yl)acetate (2.3 g, 5.46 mmol, 78% yield) as a white solid. 1H NMR (400 MHz, CHLOROFORM-d) ppm 7.40-7.44 (m, 2H) 7.25-7.35 (m, 7H) 7.00-7.04 (m, 1H) 5.88-5.94 (m, 1H) 5.80-5.88 (m, 2H) 3.74 (s, 3H) 3.63 (s, 2H) 3.59 (s, 3H); LCMS (m/z) ES+=421 (M+1).

Provenance & Evidence