Preparation and thermal behaviour of some hydrazinium dicarboxylates

Hydrazinium hydrogendicarboxylates of pimelic, suberic, azelaic, sebacic, tartaric, a-ketoglutaric and iminodiacetic acids and dihydrazinium dicarboxylates of malic, aspartic and glutamic acids have been prepared by accomplishing neutralisation of aqueous hydrazine hydrate with the respective acids. Formation of these hydrazinium salts has been confirmed by analytical, IR spectral and thermal studies. All these salts are anhydrous except hydrazinium hydrogenpimelate and iminodiacetate which are monohydrated. IR spectra of the salts register N-N stretching frequencies of the hydrazinium ion in the region 955-1000 cm(-1). The thermal decomposition behaviour of these hydrazine derivatives have been studied by simultaneous TG and DTA. Among the salts prepared, the higher dicarboxylates decompose through their respective acid intermediates. Almost, all of the intermediates decompose exothermically with the complete elimination of the sample to gaseous products. (C) 1999 Elsevier Science B.V. All rights reserved.