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Journal of Thermal Analysis and Calorimetry
Authors: Liang Xue, Feng-Qi Zhao, Xiao-Ling Xing, Zhi-Ming Zhou, Kai Wang, Hong-Xu Gao, Jian-Hua Yi, Si-Yu Xu, and Rong-Zu Hu

Introduction Triazole is a five-membered heterocyclic compound, which contains three nitrogen atoms. The three nitrogen atoms are on position 1,2,4 or 1,2,3 of a five-membered heterocycle. Triazole derivative has proven to be a

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Journal of Thermal Analysis and Calorimetry
Authors: Liang Xue, Feng-Qi Zhao, Xiao-Ling Xing, Zhi-Ming Zhou, Kai Wang, Hong-Xu Gao, Jian-Hua Yi, and Rong-Zu Hu

. Recently, many studies in developing energetic salts and energetic ionic liquids based on 1,2,3-triazole and 1,2,4-triazole as cations and nitrates, perchlorates, and dinitramides as anions have been made [ 4 – 6 ]. On the thermal aspect, kinetic and

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Journal of Flow Chemistry
Authors: Anne-Catherine Bédard, Jeffrey Santandrea, and Shawn K. Collins

The continuous-flow synthesis of a series of 11- to 26-membered macrocycles via copper-catalyzed azide-alkyne cycloaddition is reported. The approach employs homogeneous catalysis to promote formation of triazole-containing macrocycles in good to excellent yields (65–90%) at relatively high concentration (30–50 mM) using a phase separation strategy.

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Abstract  

A series of new complexes with mixed ligands of the type [ML(C3H3O2)2nH2O (((1) M=Mn, n=1; (2) M=Co(II), n=2; (3) M=Ni(II), n=4; (4) M=Cu(II), n=1.5; (5) M=Zn(II), n=0; L=3-amino-1,2,4-triazole and (C3H3O2)=acrylate anion) were synthesized and characterised by chemical analysis and IR data. In all complexes the 3-amino-1,2,4-triazole acts as bridge while the acrylate acts as bidentate ligand except for complex (5) where it is found as unidentate. The thermal behaviour steps were investigated in nitrogen flow. The thermal transformations are complex processes according to TG and DTG curves including dehydration, acrylate ion and 3-amino-1,2,4-triazole degradation respectively. The final products of decomposition are the most stable metal oxides, except for complex (4) that leads to metallic copper.

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Abstract  

In order to obtain a better understanding of thermal substituent effects in 1,2,4-triazole-3-one (TO), the thermal behavior of 1,2,4-triazole, TO, as well as urazole and the decomposition mechanism of TO were investigated. Thermal substituent effects were considered using thermogravimetry/differential thermal analysis, sealed cell differential scanning calorimetry, and molecular orbital calculations. The onset temperature of 1,2,4-triazole was higher than that of TO and urazole. Analyses of evolved decomposition gases were carried out using thermogravimetry–infrared spectroscopy and thermogravimetry–mass spectrometry. The gases evolved from TO were determined as HNCO, HCN, N2, NH3, CO2, and N2O.

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Summary  

Two 1,2,3-triazole anticonvulsants, 1-(4-methylsulfone-phenyl)-5-(4-fluoro-phenyl)-5-[14C]-1,2,3-triazole and 1-(4-sulfonamide-phenyl)-5-(4-fluoro-phenyl)-5-[14C]-1,2,3-triazole, both labeled with carbon-14 in the 5-position were prepared from para-fluoro-benzonitrile-[cyano-14C].

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Journal of Flow Chemistry
Authors: Sara Sadler, Meaghan M. Sebeika, Nicholas L. Kern, David E. Bell, Chloe A. Laverack, Devan J. Wilkins, Alexander R. Moeller, Benjamin C. Nicolaysen, Paige N. Kozlowski, Charlotte Wiles, Robert J. Tinder, and Graham B. Jones

Abstract

A facile and benign route to N-heterocycles, including triazoles and triazolopyrimidines, has been developed. Using continuous-flow microreactor technology, organic azides are prepared in situ and reacted with cyanoacetamide in a [3+2] cycloaddition to produce a variety of substituted 1,2,3-triazoles, which can be elaborated into useful building blocks. A benzyl-substituted triazole was further functionalized to an analog of the core structure of the antiplatelet agent Brilinta®. The methodology lends itself well to flow chemistry, where reaction volumes are minimized, heating and mixing are consistent, and the need for intermediate azide isolation bypassed. The scope of the process is wide, and the efficiency is high, suggesting this as a practical, green route for the production of triazolo-based heterocycles.

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useful strategy to construct such supramolecular frameworks is to employ appropriate organic linker capable of binding metal centers through direct bond formation. 1,2,4-Triazole and its derivatives are very interesting polydentate building blocks because

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Abstract  

1,2,4-triazole-3-one (TO) and guanidine nitrate (GN) have the potential to be used as alternative gas-generating agents. To obtain a better understanding of thermal decomposition properties of TO/GN mixtures, sealed cell differential scanning calorimetry, thermogravimetry–differential thermal analysis–infrared spectroscopy (TG–DTA–IR), and thermogravimetry–differential thermal analysis–mass spectrometry (TG–DTA–MS) were carried out. The endothermic peak and onset temperatures of TO/GN mixtures were lower than those of individual TO and GN. TG–DTA–IR and TG–DTA–MS showed that the mass of TO/GN mixtures decreased with heat generation and N2 evolved as the major gas during thermal decomposition. The interaction between TO and nitric acid from the dissociation of GN is proposed for the thermal decomposition of TO/GN mixtures.

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Abstract  

Thermoanalytical study of the pesticide 3-amino-1,2,4-triazole (ATA) has been carried out, using simultaneous DTA-TG in nitrogen flow, in order to know its thermal behaviour and stability. These techniques have been further complemented using evolved gas analysis and mass spectroscopy (EGA-MS). Two different stages of ATA decomposition were observed: after the first decomposition step, a mixture of compounds is obtained, according to MS data, being the principal component a compound of molecular weight 126. It is formed by a first order reaction mechanism, according to the kinetic study, withE a=124±8 kJ·mol−1. The second decomposition step takes place about 735°C, with evolution of HCN and NH3, being the final weight loss 96%.

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