Factors influencing the thermal stability of azo and bisazo compounds

  • Masoud Kazem-RostamiEmail author


The present study investigates the effects of substituents, structural rigidity, tautomerism, hydrogen bonding interaction, and spatial hindrance on the thermal stability of some azo compounds including bisazo Tröger base analogs (BATBAs). The relatively large structures of BATBAs allow assessing their thermal stability before reaching the sublimation or boiling point. BATBAs carry two identical azo groups per molecule resulting in an intense and detectable sign of decomposition. Unlike most azo dyes, BATBAs are not ionic and prevent the complexity of decomposition associated with simultaneous dehydration. A few commercial azo dyes are also analyzed to evaluate the generality of the conclusion.

Graphic abstract


Azo Bisazo Thermal stability Thermal decomposition Thermolysis Tröger base 



Dr Sadegh Faramarzi (University of Minnesota, USA), Mr Masahiro Kouno (Osaka University, Japan), Mr Mark Tran and Mr Tony Wong (Macquarie University, Australia) are appreciated for their invaluable help with computational chemistry, Japanese translation, and access to the thermoanalytical facilities, respectively. The author gratefully acknowledges the Australian Government for providing him with a Research Training Program Scholarship (IPRS-2014004) and Macquarie University for HDR (43010477) and PGRF (2016R2-1672525) funds in 2014–2017.

Supplementary material

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Supplementary material 1 (PDF 1734 kb)


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© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Faculty of Science and EngineeringMacquarie UniversityNorth RydeAustralia

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