反应详情

温度

0 °C

To a solution of 7.38 g (RS)-(4-cyano-phenylamino)-(5-ethoxy-2-fluoro-3-hydroxy-phenyl)-acetic acid ethyl ester described in example 3.5 in 220 ml THF were added 1.68 ml (S)-(+)-3-hydroxy-tetrahydrofurane and 6.48 g triphenylphosphine. The mixture was cooled to 0° C. Subsequently, 3.84 ml of diethyl azodicarboxylate were added. The solution was stirred for 3 hrs at room temperature, then evaporated. The crude product was purified by chromatography on silica gel (cyclohexane/EtOAc) to give 6.53 g of (RS)-(4-cyano-phenylamino)-[5-ethoxy-2-fluoro-3-[(R)-tetrahydro-furan-3-yloxy]-phenyl]-acetic acid ethyl ester as an off-white solid.

1. customevaporated
2. customThe crude product was purified by chromatography on silica gel (cyclohexane/EtOAc)