反应详情

(a-4) To a stirred soluiton of 0.92 parts of sodium in 32 parts of ethanol were added 5.46 parts of ethyl 1-hydroxy-6-(hydroxymethyl)-1H-benzimidazole-2-carboxylate monohydrochloride. The whole was stirred for 10 minutes and concentrated. 18 Parts of methylbenzene were added and the mixture was evaporated. 13.5 Parts of N,N-dimethylformamide and a solution of 2.84 parts of iodomethane in 4.5 parts of N,N-dimethylformamide were added. After stirring for 30 minutes, the reaction mixture was evaporated. The residue was purified by column chromatography over silica gel using a mixture of trichloromethane and acetonitrile (80:20 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was crystallized from a mixture of 2-propanol and 2,2'-oxybispropane (1:4 by volume). The product was filtered off and dried, yielding 2.5 parts (50%) of ethyl 6-(hydroxymethyl)-1-methoxy-1H-benzimidazole-2-carboxylate; mp. 110.1° C. (int. 32).

1. concentrationconcentrated
2. addition18 Parts of methylbenzene were added
3. customthe mixture was evaporated
4. addition13.5 Parts of N,N-dimethylformamide and a solution of 2.84 parts of iodomethane in 4.5 parts of N,N-dimethylformamide were added
5. stirringAfter stirring for 30 minutes
6. customthe reaction mixture was evaporated
7. customThe residue was purified by column chromatography over silica gel using
8. additiona mixture of trichloromethane and acetonitrile (80:20 by volume) as eluent
9. customThe pure fractions were collected
10. customthe eluent was evaporated
11. customThe residue was crystallized from a mixture of 2-propanol and 2,2'-oxybispropane (1:4 by volume)
12. filtrationThe product was filtered off
13. customdried