反应详情

NaOH (3.56 mL, 7.11 mmol) was added to a stirred suspension of methyl 8-(1-hydroxyethyl)-2-((R)-2-methylmorpholino)-4-oxo-4H-chromene-6-carboxylate (988 mg, 2.84 mmol) in MeOH (10 mL)/water (10 mL). The resulting mixture was stirred at RT for 1 hour then acidified to pH 2-3 with a 2N aq. HCl (7.68 mL, 7.68 mmol). The resulting precipitate was collected by filtration, washed with diethyl ether and dried to afford 8-(1-hydroxyethyl)-2-((R)-2-methylmorpholino)-4-oxo-4H-chromene-6-carboxylic acid (900 mg, 95%) as a grey solid, which was used without further purification. Mass Spectrum: M+H+ 334.

1. filtrationThe resulting precipitate was collected by filtration
2. washwashed with diethyl ether
3. customdried