abstract |
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. |