反应详情

A mixture of 79 parts of 1,3-dihydro-1-{2-[4-(phenylmethyl)-1-piperazinyl]ethyl}-2H-benzimidazol-2-one and 320 parts of methanol is hydrogenated at normal pressure and at room temperature with 10 parts of palladium-on-charcoal catalyst 10%. After the calculated amount of hydrogen is taken up, the catalyst is filtered off and the filtrate is evaporated. The oily residue is alkalized with ammonium hydroxide and a small amount of water is added. The product is extracted with trichloromethane. The extract is dried, filtered and evaporated. The oily residue solidifies on triturating in 4-methyl-2-pentanone. The product is filtered off and dried, yielding 1,3-dihydro-1-[2-(1-piperazinyl)ethyl}-2H-benzimidazol-2-one; mp. 122.6° C.

1. filtrationthe catalyst is filtered off
2. customthe filtrate is evaporated
3. additiona small amount of water is added
4. extractionThe product is extracted with trichloromethane
5. customThe extract is dried
6. filtrationfiltered
7. customevaporated
8. customon triturating in 4-methyl-2-pentanone
9. filtrationThe product is filtered off
10. customdried