反应详情

4-Dimethylaminopyridine (1.21 g) and p-toluenesulfonyl chloride (1.51 g) were added to a solution of N-tert-butoxycarbonyl-cis-4-hydroxy-D-proline methyl ester (A, 971 mg) in dichloromethane (20 mL). After stirrng at room temperature for 4 hr, the solvent was removed in vacuo. The residue was diluted with ethyl acetate, and washed with 10% citric acid, water, and brine. The organic layer was dried over anhydrous sodium sulfate and evaporated in vacuo. The residue was purified by silica gel column chromatography (chloroform then chloroform:ethyl acetate=1:50, v/v) to give the title compound (1.65 g) as a colorless oil.

1. customthe solvent was removed in vacuo
2. additionThe residue was diluted with ethyl acetate
3. washwashed with 10% citric acid, water, and brine
4. dry with materialThe organic layer was dried over anhydrous sodium sulfate
5. customevaporated in vacuo
6. customThe residue was purified by silica gel column chromatography (chloroform