反应详情

To a mixture of 2-(4-nitrophenoxy) propionic acid 47 (25 grams, 118.5 mmol) and 2-(4-nitrophenoxy)propionic acid 2-hydroxyethyl ester 48 ( 25 grams, 108 mmol) in anhydrous dichloromethane (625 ml) under nitrogen atm. was added dropwise a solution of 1,3-dicyclohexyl carbodiimide (40 g, 194 mmol) in anhydrous dichloro-methane (250 ml). The reaction mixture was stirred at room temperature for 8 hours. The solids were filtered off and dichloromethane distilled off to get crude 49. The crude 49 was purified by column chromatography on silica gel using hexane as eluant to get pure 49 (17 g, 35.1%) as a white powder.

1. filtrationThe solids were filtered off
2. distillationdichloromethane distilled off
3. customto get crude 49
4. customThe crude 49 was purified by column chromatography on silica gel