反应详情

温度

-45 °C

A solution of (trans)-1-benzoyl-4-hydroxy-L-proline methyl ester prepared as described in Example 1 Part A(2) (6 g, 24.1 mmole) was dissolved in dichloromethane and cooled to -45° C. under an argon atmosphere. To the above solution diethylaminosulfur trifluoride (5.2 ml, 42 mmole) was added dropwise. The resulting solution was stirred and warmed to -35° C. To the above solution pyridine was added dropwise (9 ml, 116 mmole). The reaction was allowed to stir overnight while warming to room temperature. The solvent was removed in vacuo and the oily residue treated with ethyl acetate and 1N HCl. The mixture was transferred to a separatory funnel, the aqueous layer removed, and the organic layer washed with additional 1N HCl, then water and saturated sodium bicarbonate solution. The organic solution was dried over sodium sulfate, filtered and concentrated to a yellow oil. The crude product was chromatographed on silica gel using 1:1 ethyl acetate:hexane as eluent. Combination and concentration of product containing fractions produced 3.9 gm (64%) of title compound as an oil.

1. temperaturewarmed to -35° C
2. stirringto stir overnight
3. temperaturewhile warming to room temperature
4. customThe solvent was removed in vacuo
5. additionthe oily residue treated with ethyl acetate and 1N HCl
6. customThe mixture was transferred to a separatory funnel
7. customthe aqueous layer removed
8. washthe organic layer washed with additional 1N HCl
9. dry with materialThe organic solution was dried over sodium sulfate
10. filtrationfiltered
11. concentrationconcentrated to a yellow oil
12. customThe crude product was chromatographed on silica gel using 1:1 ethyl acetate
13. additionCombination and concentration of product containing fractions