Synthesis of Polyamides with [(1,2,3-Benzotriazine-4-one)-3-Yl] Diphenyl Phosphate as a New Activating Agent

Abstract

Abstract A new activating reagent for amide condensation [(1,2,3-benzotriazine-4-one)-3-yl] diphenyl phosphate (BTDP), was prepared in good yield (88%) by the reaction of 3-hydroxy-1,2,3-benzotriazine-4-one with diphenyl phosphorochloridate in the presence of triethylamine (TEA) in tetrahydrofuran. Benzanilide was readily prepared with this reagent from benzoic acid and aniline at room temperature in a model reaction. The polycondensation of several aromatic dicarboxylic acids with aromatic diamines that have electron-donating substituents with BTDP in the presence of TEA in N-methyl-2-pyrrolidone proceeded at room temperature to form polyamides with inherent viscosities of 0.33–1.14 dL/g. However, polyamides from aliphatic dicarboxylic acids and diamines that carry electron-withdrawing substituents showed lower inherent viscosities than those from aromatic acids and amines with electron-donating substituents.