反应详情

To a 1-liter 3-necked round bottom flask, equipped with mechanical stirrer and two addition funnels, is added 30 g (0.2966 mole) of 3-hydroxypiperidine and 300 ml of water. The resulting solution is stirred and is cooled to ~0° C. with ice-salt bath. At this point benzyl chloroformate (51 ml, 0.356 mole) is added dropwise from one funnel and the 2N NaOH (178 ml) from the other funnel (at a slightly faster rate) during which time the temp. is maintained at ~0° C. After addition is complete, stir cold for 2 hr, then overnight at ambient temp. After this time an oily residue separates from the reaction solution, ethyl acetate is added (250 ml) to the reaction and is stirred for 1/2 hr. The phases are separated and the aqueous phase is extracted once more with EtOAc (250 ml). All organic phases are combined, washed with 1×150 ml saturated NaHCO3, 1×150 ml H20, 1×150 ml 10% HCl, 1×150 ml H20 and dried over MgSO4. The mixture is filtered and concentrated on roto-evap under reduced pressure to yield a viscous oil which is stored under vacuum to remove any residual solvents as 3-Hydroxy-1-piperidine-carboxylic Acid, Phenylmethyl Ester, a clear oil.

1. customTo a 1-liter 3-necked round bottom flask, equipped with mechanical stirrer
2. additiontwo addition funnels
3. temperatureis cooled to ~0° C. with ice-salt bath
4. temperatureis maintained at ~0° C
5. additionAfter addition
6. stirringstir cold for 2 hr
7. customovernight
8. customat ambient temp
9. customto the reaction
10. stirringis stirred for 1/2 hr
11. customThe phases are separated
12. extractionthe aqueous phase is extracted once more with EtOAc (250 ml)
13. washwashed with 1×150 ml saturated NaHCO3, 1×150 ml H20, 1×150 ml 10% HCl, 1×150 ml H20
14. dry with materialdried over MgSO4
15. filtrationThe mixture is filtered
16. concentrationconcentrated on roto-evap under reduced pressure
17. customto yield a viscous oil which
18. customto remove any residual solvents as 3-Hydroxy-1-piperidine-carboxylic Acid, Phenylmethyl Ester