反应详情

3-(3,4-Dimethoxyphenylsulfonyl)-2,2-dimethyl-7-phenylheptanoic acid (0.5 g, 1.2 mmol) is dissolved in CH2Cl2 (6 mL), cooled in ice and 2 M oxalyl chloride in CH2Cl2 (1.7 mL, 3.5 mmol) is added. The reaction is warmed to room temperature and after 4 hours the solvent is removed in vacuo and the residue azeotroped twice with chloroform. The residue is dissolved in CH2Cl2 (4 mL) and trimethylsilylhydroxylamine (0.42 mL, 3.6 mmol) is added. The reaction is stirred 15 minutes and then the solvent is removed in vacuo, CH2Cl2 (10 mL) added and the solution washed with 1 N HCl. The organic layer is dried over MgSO4 and the solvent removed in vacuo to yield 3-(3,4-dimethoxybenzenesulfonyl)-2,2-dimethyl-7-phenylheptanoic acid hydroxyamide (0.34 g, 83%): 1H NMR (300 MHz, CD3OD) δ 7.45 (dd, J=8.3, 2.0 Hz, 1H), 7.38 (d, J=2.2 Hz, 1H), 7.21-7.05 (m, 4H), 6.98-6.95 (m, 2H), 3.89 (s, 3H), 3.88 (s, 3H), 3.86-3.84 (m, 1H), 2.38-2.33 (m, 2H), 1.93-1.84 (m, 1H), 1.69-1.64 (m, 1H), 1.43 (s, 3H), 1.34-1.23 (m, 3H), 1.23 (s, 3H), 0.98-0.85 (m, 1H); MS (FAB) m/e 450 (M+H)+.

1. temperaturecooled in ice
2. customis removed in vacuo
3. customthe residue azeotroped twice with chloroform
4. dissolutionThe residue is dissolved in CH2Cl2 (4 mL)
5. customthe solvent is removed in vacuo, CH2Cl2 (10 mL)
6. additionadded
7. washthe solution washed with 1 N HCl
8. dry with materialThe organic layer is dried over MgSO4
9. customthe solvent removed in vacuo