反应详情

A solution of 2.30 g (RS)-4-{3-[(4-cyano-phenylamino)-ethoxycarbonyl-methyl]-5-ethoxy-2-fluoro-phenoxy}-piperidine-1-carboxylic acid tert-butyl ester in 40 ml dichloromethane was cooled to 0° C. and treated dropwise with 3.25 ml trifluoroacetic acid. The reaction mixture was warmed to r.t. within 3 hrs, then again cooled to 0° C. and treated with 20 ml of 10% Na2CO3 solution. The product was extracted with dichloromethane. The organic layer was dried over MgSO4, filtrated and evaporated to give 1.55 g (RS)-(4-cyano-phenylamino)-[5-ethoxy-2-fluoro-3-(piperidin-4-yloxy)-phenyl]-acetic acid ethyl ester as an off-white solid foam which was used for the next step without further purification. MS: 442.3 ([M+H]+).

1. temperatureagain cooled to 0° C.
2. extractionThe product was extracted with dichloromethane
3. dry with materialThe organic layer was dried over MgSO4
4. filtrationfiltrated
5. customevaporated