反应详情

4.9 g (0.12 mole) of sodium borohydride was suspended at room temperature in a solution of 24.9 g (0.10 mole) of isobutyl (R)-(+)-2-(1-isobutoxyethoxy)propionate dissolved in 100 ml of 1,2-dichloroethane. Thereto was dropwise added slowly 24.0 ml (0.60 mole) of methanol with stirring so that the internal temperature of the reaction system could be kept at 40° C. After the completion of the dropwise addition, the resulting mixture was stirred at room temperature with the disappearance of the raw material being monitored by GC, to give rise to a reaction. 20 hours were necessary. Then, 50 ml of water was added, followed by stirring for 0.5 hour. The organic layer was separated. The water layer was subjected to extraction with 50 ml of toluene. The two organic layers were combined and washed with 30 ml of water and 30 ml of a saturated aqueous sodium chloride solution in this order. The washed solution was dried over anhydrous sodium sulfate and then subjected to vacuum distillation to remove the solvent. The resulting concentrate was subjected to distillation to obtain 16.3 g (yield: 92.6%) of an oily title compound (diastereomixture).

1. customcould be kept at 40° C
2. additionAfter the completion of the dropwise addition
3. customto give rise
4. customto a reaction
5. custom20 hours
6. stirringby stirring for 0.5 hour
7. customThe organic layer was separated
8. extractionThe water layer was subjected to extraction with 50 ml of toluene
9. washwashed with 30 ml of water and 30 ml of a saturated aqueous sodium chloride solution in this order
10. dry with materialThe washed solution was dried over anhydrous sodium sulfate
11. distillationsubjected to vacuum distillation
12. customto remove the solvent
13. concentrationThe resulting concentrate
14. distillationwas subjected to distillation