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84. The Influence of Solvents and Catalysts on the Thermal Behavior of Azidohetarenes in DSC Measurements
Stadlbauer W., Hojas G., in Proceedings of ECSOC-5, The Fifth International Electronic Conference on Synthetic Organic Chemistry (ECSOC-5), 2001; C.O. Kappe, P. Merino, A. Marzinzik, H. Wennemers, T. Wirth, J.-J. Vanden Eynde and S.-K. Lin, (Ed), MPDI (Switzerland); CD-ROM edition, ISBN 3-906980-06-5, 2001.

Abstract: The reaction temperatures obtained from DSC measurements did in several cases not agree with the experimentally obtained results in synthetic reactions. In most cases it was found that lower temperatures were necessary. So we studied the influence of solvents on the reaction or decomposition temperatures of a number of azides in order to obtain data which are comparable with the real experimental results of decomposition reactions under synthetic conditions.

A further point of interest was to obtain information not only about different solvents but also about catalysts. So we performed some thermal reactions in DSC crucibles using different acid catalysts to study the effects on the thermal behavior of the samples.

The results obtained in this study show that solvent effects on the thermolysis of azidohetarenes without reactive ortho substituents in diphenylether have mainly the effect to give a uniform decomposition temperature of 140-160 oC. With acid catalysts, the reaction temperatures were up to 90 oC lower than without catalysts, which must be considered in reactions with such catalysts. Azidohetarenes with reactive ortho substituents such as 8 show in solution a reaction temperature which is about 60 oC lower than in the solid state. This result is important in planning thermal strain of azides.v

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