反应详情

温度

25 °C

A solution of (3S)-3-ethyl-7-fluoro-4-[(4-methoxyphenyl)sulfonyl]-1-methyl-3,4-dihydroquinoxalin-2(1H)-one (0.27 g, 0.7 mmol)) and tetrabutylamonium iodide (0.77 g, 2.09 mmol) in methylene chloride (20 mL) was cooled to −78° C. and treated with a 1M solution of boron trichloride in methylene chloride (3.5 mL, 3.5 mmol) via syringe. The cooling bath was removed and the solution was stirred at 25° C. for 3 hours. The reaction was quenched with a saturated aqueous solution of ammonium chloride. The organic phase was separated, dried over magnesium sulfate and concentrated in vacuo. The crude oil was purified via flash column chromatography (SiO2, 40% ethyl acetate:hexane) to afford 0.2 g (78%) of (3S)-3-ethyl-7-fluoro-4-[(4-hydroxyphenyl)sulfonyl]-1-methyl-3,4-dihydroquinoxalin-2(1H)-one as white solid. MS (ESI) m/z 365 ([M+H]+); MS (ESI) m/z 363 ([M−H]−); Anal. Calcd for C17H17FN2O4S: C, 56.03; H, 4.70; N, 7.69. Found: C, 56.12; H, 4.03; N, 7.45.

1. customThe cooling bath was removed
2. customThe reaction was quenched with a saturated aqueous solution of ammonium chloride
3. customThe organic phase was separated
4. dry with materialdried over magnesium sulfate
5. concentrationconcentrated in vacuo
6. customThe crude oil was purified via flash column chromatography (SiO2, 40% ethyl acetate:hexane)