反应详情

To a solution of 2-(dibenzylamino)-3-(difluoromethoxy)propanoic acid (335.4 mg, 1 mmol) and triethylamine (404.8 mg, 4 mmol) in THF (5 mL) at −5° C., isobutyl chloroformate (143.5 mg, 1.05 mmol) was added dropwise. After 20 minutes, 4-fluorobenzylamine (137.5 mg, 1.1 mmol) was added and the reaction mixture allowed to warm up to room temperature. The mixture then was diluted with ethyl acetate and washed with water, 0.5 N HCl and Brine. The organic layer was dried over magnesium sulphate, concentrated with silica gel and purified by column chromatography, eluting with 10˜20% ethyl acetate in hexanes, to give 2-dibenzylamino-3-difluoromethoxy-N-(4-fluorobenzyl)propionamide (395 mg, 89.2%) as a colorless oil. 1H NMR (300 MHz, CDCl3): δ(ppm) 7.56 (t, 1H), 6.98-7.32 (m, 14H), 6.35 (wt, 1H), 4.61 (dd, 1H), 4.41 (m, 3H), 3.86 (d, 2H), 3.70 (d, 2H) and 3.68 (m, 1H).

1. washwashed with water, 0.5 N HCl and Brine
2. dry with materialThe organic layer was dried over magnesium sulphate
3. concentrationconcentrated with silica gel
4. custompurified by column chromatography
5. washeluting with 10˜20% ethyl acetate in hexanes