反应详情

486 mg of NaBH4 are added, in portions, to a suspension of 4.57 g of 4-[4-{[(benzyloxy)carbonyl]amino}-3-(propan-2-yloxy)phenyl]-3-methoxy-1-methylpyridinium iodide in 100 ml of ethanol brought to 5° C. The reaction medium is stirred for 1 h 30 at ambient temperature. 50 ml of water, 50 ml of a saturated aqueous sodium bicarbonate solution and 100 ml of ethyl acetate are added. The two phases are separated, and the aqueous phase is washed with twice 50 ml of ethyl acetate. The combined organic phases are dried over magnesium sulfate, filtered and evaporated. Purification is carried out by flash chromatography on silica gel (40-63 μm), elution being carried out with a mixture of dichloromethane and (MeOH+10% NH4OH) (99/1 to 90/10). 1.87 g of benzyl [4-(5-methoxy-1-methyl-1,2,3,6-tetrahydropyridin-4-yl)-2-(propan-2-yloxy)phenyl]carbamate are obtained in the form of an orangey-coloured oil.

1. custombrought to 5° C
2. customThe two phases are separated
3. washthe aqueous phase is washed with twice 50 ml of ethyl acetate
4. dry with materialThe combined organic phases are dried over magnesium sulfate
5. filtrationfiltered
6. customevaporated
7. customPurification
8. washis carried out by flash chromatography on silica gel (40-63 μm), elution
9. additionbeing carried out with a mixture of dichloromethane and (MeOH+10% NH4OH) (99/1 to 90/10)