The invention describes an improved process for the manufacture of a Flecainide intermediate viz N-(pyridin-2-ylmethyl)-2,5-bis(2,2,2-trifluoroethoxy)benzamide (II). It consists of reacting 2,5-bis(2,2,2-trifluoroethoxy)benzoic acid with an acid chloride in a solvent mixture in presence of a base at −10 to −50° C. The resulting mixed anhydride is then condensed with 2-aminomethylpyridine at −10 to −40° C. and the resulting product after aqueous workup is purified by crystallization. This affords the intermediate II in vastly improved yields and quality. The intermediate II on catalytic hydrogenation affords N-(2-piperidinylmethyl)-2,5-bis(2,2,2-trifluoroethoxy)benzamide (Flecainide), isolated as its acetate.
本发明描述了一种改进的方法,用于制造一种Flecainide中间体,即N-(
吡啶-2-甲基)-2,5-双(2,2,2-三
氟乙氧基)苯甲酰胺(II)。该方法包括在溶剂混合物中,在碱的存在下,将
2,5-双(2,2,2-三氟乙氧基)苯甲酸与酸
氯化物反应,在-10至-50℃下进行。然后将所得的混合酸酐与2-
氨甲基吡啶在-10至-40℃下缩合,经
水工作后,通过结晶纯化得到所述的中间体II,其产率和质量得到了极大的提高。在催化氢化后,中间体II得到N-(2-
哌啶基甲基)-2,5-双(2,2,2-三
氟乙氧基)苯甲酰胺(Flecainide),并以其
醋酸盐的形式分离。