反应详情

To a solution (15 ml) of 3 g of methyl 21-(2-hydroxy-3,4-dimethoxy-6-methylbenzoyl)heneicosanoate in ethyl acetate are added 0.015 ml of 60% perchloric acid and 600 mg of 5% palladium-on-carbon, and catalytic reduction is carried out at a 70° C. using hydrogen gas at the pressure of 100 kg/cm2. The catalyst is filtered off and the filtrate is washed in sequence with ice water, a saturated aqueous sodium bicarbonate solution and a saturated aqueous sodium chloride solution, and dried over anhydrous sodium sulfate. Removal of the solvent by distillation under reduced pressure gives colorless crystals of methyl 22-(2-hydroxy-3,4-dimethoxy-6-methylphenyl)docosanoate. m.p. 71°-72.5° C.

1. customis carried out at a 70° C.
2. filtrationThe catalyst is filtered off
3. washthe filtrate is washed in sequence with ice water
4. dry with materiala saturated aqueous sodium bicarbonate solution and a saturated aqueous sodium chloride solution, and dried over anhydrous sodium sulfate
5. customRemoval of the solvent
6. distillationby distillation under reduced pressure