反应详情

To a mixture of 4-nitrophenoxyacetic acid-2-hydroxyethyl ester 41 (100 g, 410 mmol) and 2-(4-nitrophenoxy)propionic acid 47 (95 g, 450 mmol ) in anhydrous dichloro-methane (1000 ml) under nitrogen atm. was added a solution of 1,3-dicyclohexylcarbodiimide (240 g, 1160 mmol) in anhydrous dichloromethane (600 ml) dropwise. The reaction mixture was stirred at room temperature for 12 hrs. The solids were filtered off and dichloromethane distilled off to get crude 55. The crude 55 was purified by column chromatography on silica gel using benzene as eluant to give pure 55 (53 g, 29%) as a yellow low melting solid.

1. filtrationThe solids were filtered off
2. distillationdichloromethane distilled off
3. customto get crude 55
4. customThe crude 55 was purified by column chromatography on silica gel