反应详情

To a stirred solution of (S)-(−)-2-methyl-2-propanesulfinamide (854 mg, 7 mmol) and 1,4-dioxaspiro[4,5]decan-8-one (1 g, 6.40 mmol) in tetrahydrofuran (13 mL) was added titanium(IV) ethoxide (5.11 mL, 16 mmol). The mixture was stirred for 4 h at room temperature, poured over stirring saturated aqueous sodium bicarbonate (10 mL) and acetonitrile (10 mL), and stirred for 20 minutes. Magnesium sulfate was added and the mixture was stirred for 20 minutes, filtered over celite and concentrated. The residue was purified by column chromatography on silica gel (10:90 to 70:30 ethyl acetate:hexanes gradient) to afford N-(1,4-dioxaspiro[4.5]dec-8-ylidene)-2-methylpropane-2-sulfinamide (466 mg, 1.8 mmol, 28% yield) as a white solid. MS ESI: [M+H]+ m/z 260.

1. additionpoured
2. stirringstirred for 20 minutes
3. stirringthe mixture was stirred for 20 minutes
4. filtrationfiltered over celite and
5. concentrationconcentrated
6. customThe residue was purified by column chromatography on silica gel (10:90 to 70:30 ethyl acetate:hexanes gradient)