A mixture of 4-(benzyloxy)aniline hydrochloride (2.21 g), 4-methylbenzenesulfonic acid hydrate (0.178 g), and (2-chloropyridin-3-yl)acetic acid (Journal of Medicinal Chemistry, 1990, 33, 2697-2706.) (1.61 g) in 1-pentanol (15 mL) was stirred at 140° C. for 24 h. After cooling to room temperature, the mixture was added to SiO2, and the mixture was concentrated and purified by column chromatography (silica gel, eluted with 0%-50% EtOAc in hexane) to give 1-[4-(benzyloxy)phenyl]-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one (1.39 g) as a pale yellow solid.
