反应详情

To a mixture of 4-aminophenoxyacetic acid methyl ester 15 (20 g, 110.5 mmol) and benzyloxyacetic acid (20.4 g, 123 mmol) in anhydrous dichloromethane (200 ml) under nitrogen atm. was added dropwise a solution of 1,3-dicyclohexylcarbodiimide (63.2 g, 306 mmol) in anhydrous dichloromethane (80 ml). The reaction mixture was stirred at room temp. for 12 hrs. The solids were filtered off, the dichloromethane solution was washed with 5% sodium bicarbonate solution (100 ml), water (100 ml), dried over sodium sulphate, and distilled to get crude 66. The crude 66 was purified by column chromatography on silica gel using benzene as eluant to get pure 66 (25 g, 68.9%) as a white powder. M.p: 76-77.5° C.

1. filtrationThe solids were filtered off
2. washthe dichloromethane solution was washed with 5% sodium bicarbonate solution (100 ml), water (100 ml)
3. dry with materialdried over sodium sulphate
4. distillationdistilled
5. customto get crude 66
6. customThe crude 66 was purified by column chromatography on silica gel