反应详情

To a solution of (R)-thiazolidine-4-carboxylic acid (20.0 g) in a mixture of water (100 ml) and tetrahydrofuran (100 ml) was added a solution of 4-nitrobenzyloxycarbonyl chloride (32.4 g) in tetrahydrofuran (60 ml) under ice-cooling with stirring, keeping the pH between 8.5 and 9.0 with 4N aqueous sodium hydroxide. After stirring for 30 minutes, the mixture was adjusted to pH 1 with concentrated hydrochloric acid, extracted with ethyl acetate, dried over magnesium sulfate, and evaporated under reduced pressure to give (R)-3-(4-nitrobenzyloxycarbonyl)thiazolidine-4-carboxylic acid (54.5 g) as a crude syrup.

1. temperaturecooling
2. stirringAfter stirring for 30 minutes
3. extractionextracted with ethyl acetate
4. dry with materialdried over magnesium sulfate
5. customevaporated under reduced pressure