反应详情

5,7-dichloro-3-{[2-methyl-3-(trifluoromethyl)phenyl]methyl}-3H-imidazo[4,5-b]pyridine (200 mg, 0.555 mmol) was suspended in Methanol (1.5 mL), sodium methoxide (0.150 mL, 0.656 mmol) was added and the mixture was irradiated in a microwave oven for 90 min at 110° C. Conversion to desired product was observed by LC/MS (5,7-dimethoxy product, 5-methoxy isomer and 7-OH-5-Cl derivative observed by mass as well). The mixture was diluted with water and the precipitate formed was collected by filtration, washed with water and dried. The solid was purified on silica gel (ISCO 0-60% EtOAc in hexanes) to give 5-chloro-7-(methyloxy)-3-{[2-methyl-3-(trifluoromethyl)phenyl]methyl}-3H-imidazo[4,5-b]pyridine (125 mg, 0.351 mmol, 63.3% yield) as a white powder. Additional material was prepared from 120 mg of 5,7-dichloro-3-{[2-methyl-3-(trifluoromethyl)phenyl]methyl}-3H-imidazo[4,5-b]pyridine, irradiated in a microwave for 30 min at 110° C. in the presence of NaOMe. After work-up, 5-chloro-7-(methyloxy)-3-{[2-methyl-3-(trifluoromethyl)phenyl]methyl}-3H-imidazo[4,5-b]pyridine (109 mg, 0.306 mmol, 55.2% yield) was obtained and carried on without further purification to the next step. MS (ES+) m/e 356 (MH+).