反应详情

A mixture of 102 parts of ethyl 4-(3-chloro-3-oxopropyl)-1-piperidinecarboxylate, 45 parts of 2,6-dimethylpyridine and 630 parts of tetrahydrofuran was hydrogenated at normal pressure and at room temperature with 5 parts of palladium-on-charcoal catalyst 10%. After the calculated amount of hydrogen was taken up, the catalyst was filtered off and the filtrate was evaporated. The reside was dissolved in 650 parts of dichloromethane. The solution was washed twice with 100 parts of a hydrochloric acid solution 5% and twice with 100 parts of water, dried filtered and evaporated. The residue was distilled, yielding 71.1 parts (81%) of ethyl 4-(3-oxopropyl)-1-piperidinecarboxylate; bp. 130°-135° C. at 133 Pa (int. 46).

1. filtrationthe catalyst was filtered off
2. customthe filtrate was evaporated
3. dissolutionThe reside was dissolved in 650 parts of dichloromethane
4. washThe solution was washed twice with 100 parts of a hydrochloric acid solution 5% and twice with 100 parts of water
5. customdried
6. filtrationfiltered
7. customevaporated
8. distillationThe residue was distilled