反应详情

温度

-5 °C

11.2 g of (2S)-S-benzoyl-3-mercapto-2-methylpropanoic acid and 5.1 g of triethylamine are dissolved in 100 ml of dehydrated tetrahydrofuran. To this solution, 6.8 g of isobutyl chloroformate is added dropwise while stirring at the temperature maintained -5° C. After the addition, the mixture is stirred at room temperature for 10 minutes. To this solution, 10.8 g of (4R)-2-(2-thienyl)-4-thiazolidinecarboxylic acid and 5.1 g of triethylamine dissolved in the mixed solution of 5 ml of tetrahydrofuran and 15 ml of water are added. The mixture is stirred at room temperature for 30 minutes. To this reaction mixture, 200 ml of water is added and the mixture is extracted with ethyl acetate. The aqueous layer is acidified with dilute hydrochloric acid and the produced oil is extracted with ethyl acetate. The ethyl acetate layer is washed with water, dried over anhydrous sodium sulfate, and concentrated in vacuo to give the titled compound, yield 10.3 g (49%), mp. 136°-137° C. (benzene, [α]D25 +79.6° (c=1.0, methanol).

1. additionAfter the addition
2. stirringthe mixture is stirred at room temperature for 10 minutes
3. additionare added
4. stirringThe mixture is stirred at room temperature for 30 minutes
5. extractionthe mixture is extracted with ethyl acetate
6. extractionthe produced oil is extracted with ethyl acetate
7. washThe ethyl acetate layer is washed with water
8. dry with materialdried over anhydrous sodium sulfate
9. concentrationconcentrated in vacuo