在酸催化下，氰基可以醇解直接生成酯。通常使用的催化剂是浓硫酸或氯化氢，只适用于伯醇，因为叔醇和仲醇在硫酸作用下会生成烯，硫酸和释放出的氨成盐。
腈的醇解，醇兼作溶剂，其用量比较大，一般是理论量的4～5倍；硫酸的用量也要超过理论用量的0.5～1倍。
1-(4-Cyanoenyl)-piperazine (11 mmol) was dissolved in 5 N a solution concentrated sulfoc and methanol (15 ml) and stirred in a sealed tubeat 110℃for 3 h. After evaporationof the solvent, the residue was dissolved in water and extracted with ethylacetate. of sodium carbonate to the water phase until pH 9 results inthe precipitation of a white solid which was filtered off and dried (vacuum). Awhite powder with Rf 0.59 (CH2Cl2/MeOH = 9:1)was obtained. 4-piperazin-1-yl-benzoic acid methyl 。
【 Patent; Mwassbach, Martin; Publ.: US2001/16207A1 (2001/08/23), Appl.: US2001-778302 (2001/02/07)】
1-,2-Bis(4-cyanobenzylthio)ethyl]-1H-imidazole hydrochloride (1.43 g)was added to methanol (50 mL) which had been saturated with hydrogen chlorideat 0℃. The resulting solutionwas stirred under reflux for 20 h and then concentrated. The gummy residue was partitioned between CH2Cl2and aqueous NaHCO3, and the CH2Cl2 layer waswashed with brine and dried over Na2SO4. Removal of the CH2Cl2left a gum which was hromatographed on silicic acid (60 g) with CH2Cl2/CH3OH (95:5), to afford 1.1 g of the free base of the titlecompound as a viscous oil. Treatment of a solution of the base in CH3OH-etherwith hydrogen chloride provided colorless crystals of 1-[2,2-Bis(4-carbomethoxybenzylthio)ethyl]-1H-imidazoleHydrochloride.
【Patent; Brwastol-MyersCompany; Publ.: US4458079 A1 (1984/07/03), Appl.: US1980-176422 (1980/08/08)】
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