反应详情

A solution of ethyl 2-ethoxy-1-[[2′-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]benzimidazole-7-carboxylate (0.24 g) and 1N NaOH (1.5 ml) in ethanol (4 ml) was stirred at 80° C. for one hour. The reaction mixture was concentrated, and the concentrate was extracted with water and ethyl acetate. The aqueous layer was adjusted to pH 3–4 with 1N-HCl to give crystals. Recrystallization of the crystals from ethyl acetate-methanol afforded colorless crystals (0.15 g, 67%), m.p. 183–185° C.

1. concentrationThe reaction mixture was concentrated
2. extractionthe concentrate was extracted with water and ethyl acetate
3. customto give crystals
4. customRecrystallization of the crystals from ethyl acetate-methanol afforded colorless crystals (0.15 g, 67%), m.p. 183–185° C.