反应详情

To a stirred solution of compound 1H (500 mg, 2.2 mmol) in CH2Cl2 (5 mL) was added a solution of O-mesitylenesulfonylhydroxylamine (650 mg, 3 mmol) in CH2Cl2 (2 mL) at −10° C., and the stirring was continued for 20 min between −10 to 0° C. It was concentrated, added to a mixed solvent of benzene and methanol (30 mL, 3:1) followed by a slurry of basic alumina (25 g) in methanol (20 mL). The reaction mixture was stirred at RT overnight, and alumina solid was removed by filtration. Purification by silica gel chromatography (5% to 100% EtOAc in hexanes, then 5% methanol in EtOAc) provide mixtures of the title compounds 1I and 1J (total 360 mg) as a yellow oil. MS (ES) m/z 246 [M+H]+.

1. concentrationIt was concentrated
2. additionadded to a mixed solvent of benzene and methanol (30 mL, 3:1)
3. customalumina solid was removed by filtration
4. customPurification by silica gel chromatography (5% to 100% EtOAc in hexanes