反应详情

To a magnetically stirred mixture of 4-methyl-4-phenyl-tetrahydro-pyran (1.10 g, 6.24 mmol) in dry methylene chloride (50 mL) cooled in an ice bath was added 2.07 mL of chlorosulfonic acid (3.64 g, 31.2 mmol) dropwise under dry nitrogen. The reaction was stirred overnight at room temperature; the reaction was added to ice and the product was extracted with methylene chloride (3×100 mL). The organic layer was washed with saturated brine, dried (MgSO4), filtered and concentrated. e product was chromatographed on silica gel using ethyl acetate-hexane mixtures (2-20% hexane). Removal of solvent provided pure product as a colorless syrup which crystallized on standing: 1H NMR (CDCl3) δ 7.99 (d, 2H, J=8.8 Hz), 7.56 (d, 2H, J=8.8 Hz), 3.79 (ddd, 1H, J=11.7 Hz, J=8.4 Hz, J=3.3 Hz), 3.70 (ddd, 1H, J=11.7 Hz, J=6.0 Hz, J=3.8 Hz), 2.11 (ddd, 1H, J=13.8 Hz, J=8.4 Hz, J=3.8 Hz), 1.81 (dm, 1H, J=13.8 Hz), 1.35 (s, 3H). MS: m/z 275 (M++1).

1. temperaturecooled in an ice bath
2. additionthe reaction was added to ice
3. extractionthe product was extracted with methylene chloride (3×100 mL)
4. washThe organic layer was washed with saturated brine
5. dry with materialdried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated
8. custome product was chromatographed on silica gel
9. customRemoval of solvent
10. customprovided pure product as a colorless syrup which
11. customcrystallized