反应详情

To a stirred solution of 152 parts of sodium hydroxide in 1000 parts of water was added a solution of 249.5 parts of 4-piperidinepropanoic acid acetate (1:1) in 900 parts of water. 270 Parts of tetrahydrofuran were added. After cooling in a 2-propanone/CO2 -bath, a solution of 119.4 parts of ethyl carbonochloridate in 270 parts of tetrahydrofuran was added dropwise. Upon completion, stirring was continued for 3 hours at a temperature between 0°-5° C. The whole was washed twice with 420 parts of 1,1-oxybisethane. The aqueous phase was acidified with concentrate hydrochloric acid. The product was extracted three times with 520 parts of dichloromethane. The whole was evaporated. The oily residue was suspended five times in 210 parts of petroleumether and the latter was decanted each time. The residue was evaporated to dry, yielding 200 parts (93%) of 1-(ethoxycarbonyl)-4-piperidinepropanoic acid as an oily residue (int. 44).

1. washThe whole was washed twice with 420 parts of 1,1-oxybisethane
2. extractionThe product was extracted three times with 520 parts of dichloromethane
3. customThe whole was evaporated
4. customthe latter was decanted each time
5. customThe residue was evaporated
6. customto dry