Hydrazine, poly condensation with

Cyanopyrazine with dicyanodiamide [(NH2CN)2] gave the 2-(4, 6 -diamino-triazin-2 -yl)pyrazine (63), with o-phenylenediamine in the presence of poly-phosphoric acid at 250 gave 2-(benzimidazol-2 -yl)pyrazine, and with hydrazine gave 2-(C-hydrazino-C-iminomethyl)pyrazine, which condensed with benzil to 2-(5, 6 -diphenyl-as-triazin-3 -yl)pyrazine (64) (1441). 

Finally, syntheses of poly(arylene ether)s by modification of precursors should be mentioned. All the syntheses described in [271-273] were based on poly(ether ketone)s derived from phthaloyl bisfluorobenzene (172). The tertiary amine catalyzed condensation with benzylamine yielded the poly(isoquinoline ether)s (171), whereas condensation with hydrazine produced the polyphthalazines (173). High glass transitions and high thermostabilities are characteristic for all these poly(arylene ether)s. 

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