反应详情

3.2 34.7 ml of aqueous 1 N sodium hydroxide solution are added to a solution of 10.1 g (about 20.5 mmol) of ethyl [2-(5-chlorothiophen-2-yl)-1H-benzimidazol-5-yl]acetate in 70 ml of methanol, and the mixture is stirred at room temperature for 3 days. The reaction mixture is evaporated, and the residue is taken up in 25 ml of water. A pH of 4.5 is set by addition of conc. hydrochloric acid. The resultant precipitate is filtered off, washed with water and dried, giving [2-(5-chlorothiophen-2-yl)-1H-benzimidazol-5-yl]acetic acid as a yellowish solid; ESI 293.

1. customThe reaction mixture is evaporated
2. additionA pH of 4.5 is set by addition of conc. hydrochloric acid
3. filtrationThe resultant precipitate is filtered off
4. washwashed with water
5. customdried