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Thermal stability of N-heterocycle-stabilized iodanes - a systematic investigation.

ABSTRACT: The thermal stability of pseudocyclic and cyclic N-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-?³-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. Peak decomposition temperatures (T _peak) were observed within a wide range between 120 and 270 °C. Decomposition enthalpies (?H _dec) varied from -29.81 to 141.13 kJ/mol. A direct comparison between pseudocyclic and cyclic NHIs revealed high T _peak but also higher ?H _dec values for the latter ones. NHIs bearing N-heterocycles with a high N/C-ratio such as triazoles show among the lowest T _peak and the highest ?H _dec values. A comparison of NHIs with known (pseudo)cyclic benziodoxolones is made and we further correlated their thermal stability with reactivity in a model oxygenation.

SUBMITTER: Boelke A

PROVIDER: S-EPMC6774080 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Thermal stability of N-heterocycle-stabilized iodanes - a systematic investigation.

Boelke Andreas A Vlasenko Yulia A YA Yusubov Mekhman S MS Nachtsheim Boris J BJ Postnikov Pavel S PS

Beilstein journal of organic chemistry 20190927

The thermal stability of pseudocyclic and cyclic N-heterocycle-stabilized (hydroxy)aryl- and mesityl(aryl)-λ3-iodanes (NHIs) through thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) is investigated. Peak decomposition temperatures (T peak) were observed within a wide range between 120 and 270 °C. Decomposition enthalpies (ΔH dec) varied from -29.81 to 141.13 kJ/mol. A direct comparison between pseudocyclic and cycl ...[more]

PMID: 31598183

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