反应详情

28.3 G. (0.129 moles) of 1-cyclohexyl-1-butyl chloroformate is added over a period of 20 minutes at a temperature of 20° C to a stirred suspension of 25.1 g. (0.125 moles) of 2-(4-thiazolyl)-benzimidazole and 200 ml. of pyridine. A clear solution initially results which is followed by the precipitation of pyridine hydrochloride. The reaction mixture is then stirred for 16 hours at room temperature filtered and the filtrate evaporated to dryness in vacuo. The product is extracted from the residue with 250 ml. of methylene chloride which is filtered and the filtrate washed twice with 250 ml. of 0.25 N-hydrochloric acid and 200 ml. of saturated sodium bicarbonate solution. The methylene chloride is dried, treated with charcoal, filtered and evaporated to dryness in vacuo. The residual oil is chromatographed on a column of silica gel eluting with benzene affording 21.6 g. (45%) of a pale yellow viscous oil. Thin layer chromatography demonstrates that the oil is pure material which analyzes as 1-(1-cyclohexylbutoxycarbonyl)-2-(4-thiazolyl)-benzimidazole.

1. customA clear solution initially results which
2. customis followed by the precipitation of pyridine hydrochloride
3. filtrationfiltered
4. customthe filtrate evaporated to dryness in vacuo
5. extractionThe product is extracted from the residue with 250 ml
6. filtrationof methylene chloride which is filtered
7. washthe filtrate washed twice with 250 ml
8. dry with materialThe methylene chloride is dried
9. additiontreated with charcoal
10. filtrationfiltered
11. customevaporated to dryness in vacuo
12. customThe residual oil is chromatographed on a column of silica gel eluting with benzene affording 21.6 g