Dicarboxylic acid amides, mixed

Mixed dicarboxylic acid amides from dicarboxylic acid isoimides... [Pg.71]

An improved dissymmetrization of imidazole-4,5-dicarboxylic acid 869 for the synthesis of Ar,AT -disubstituted dicarboxamides 872 involves the preparation of pyrazine-dione diphenyl ester 870. Selective amide formation at the pyrazine carbonyl at low temperatures affords the mixed amide ester 871, which is subsequently converted into 872 (Scheme 213) <2002JOC7151>. [Pg.259]

Mixed dicarhoxylic acid amides dicarboxylic acid imides... [Pg.80]

To identify the most favorable reaction conditions factors such as time, temperature, rate of addition, concentration and solvent composition were investigated f53]. Only low molecular weight polyamides were obtained in the polycondensation of various types of phosphite-amides with dicarboxylic acids (Scheme XXIV). It was also shown that a side reaction like the formation of a mixed anhydride intermediate not only diminishes the yield and molecular weight of the polymer but might contribute also to racemization following Scheme XXIV consequently this method has been abandoned. [Pg.34]

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