反应详情

The [2-(1,4-benzodioxan-2-yl)-2-hydroxyethyl]amine prepared in Preparation A' (50 g) and piperidone (85 g) are dissolved in 500 ml of ethanol. Seventy-five grams of sodium cyanoborohydride is added, and the mixture is maintained at room temperature for 12 hours and cooled and evaporated. The product is recovered by adding aqueous ammonia to the residue and extracting with methylene chloride. Three 100 ml portions of methylene chloride are used which are combined, washed twice with 50 ml of water and evaporated to a semi-solid. Upon addition of ether, the product crystallizes and is recovered by filtration. The resulting crude mixture is boiled gently in 100 ml of diethyl ether and then evaporated to a residue and triturated with hexane to yield pure material, 4-{[2-(1,4-benzodioxan-2-yl)-2-hydroxyethyl]amino}piperidine.

1. temperaturecooled
2. customevaporated
3. customThe product is recovered
4. additionby adding aqueous ammonia to the residue
5. extractionextracting with methylene chloride
6. washwashed twice with 50 ml of water
7. customevaporated to a semi-solid
8. additionUpon addition of ether
9. customthe product crystallizes
10. filtrationis recovered by filtration
11. customevaporated to a residue
12. customtriturated with hexane