反应详情

To a solution of 2-methyl-5-nitro-benzenesulfonic acid, 2,2-dimethylpropyl ester, Example 24 (1.0 g, 3.48 mmol) in dry carbon tetrachloride (50 mL) was added 126 mg (0.52 mmol) of benzoyl peroxide and 712 mg (4.0 mmol) of recrystallized N-bromosuccinimide. A reflux condensor was attached and the mixture was heated to reflux and stirred overnight. After cooling to room temperature the reaction mixture was diluted with ethyl acetate (250 mL) and washed with water, followed by saturated sodium bicarbonate, and then brine. The organic layer was dried (MgSO4) and concentrated to dryness on a rotary evaporator. Purification by flash column chromatography using 10% ethyl acetate in hexanes gave 560 mg (44%) of the title compound as a white solid: 1HNMR (CDCl3): d 8.83 (d, J=2 Hz, 1H), 8.48 (dd, J=2 Hz, 9 Hz, 1H), 7.92 (d, J=9 Hz, 1H), 4.96 (s, 2H), 3.85 (s, 2H), 1.0 (s, 9H); MS (ES-NEG): [M−H] 364/366; Anal. Calc. for C12H16BrNO5S: C, 39.35; H, 4.40; N, 3.82. Found: C, 39.88; H, 4.16; N, 3.85.

1. temperaturethe mixture was heated
2. temperatureto reflux
3. washwashed with water
4. dry with materialThe organic layer was dried (MgSO4)
5. concentrationconcentrated to dryness on a rotary evaporator
6. customPurification by flash column chromatography