94-97-3Relevant articles and documents
Synthesis of amino, azido, nitro, and nitrogen-rich azole-substituted derivatives of 1H-benzotriazole for high-energy materials applications
Srinivas, Dharavath,Ghule, Vikas D.,Tewari, Surya P.,Muralidharan, Krishnamurthi
, p. 15031 - 15037 (2012)
The amino, azido, nitro, and nitrogen-rich azole substituted derivatives of 1H-benzotriazole have been synthesized for energetic material applications. The synthesized compounds were fully characterized by 1H and 13C NMR spectroscopy, IR, MS, and elemental analysis. 5-Chloro-4-nitro-1H-benzo[1,2,3]triazole (2) and 5-azido-4,6-dinitro-1H-benzo[1, 2,3]triazole (7) crystallize in the Pca21 (orthorhombic) and P2 1/c (monoclinic) space group, respectively, as determined by single-crystal X-ray diffraction. Their densities are 1.71 and 1.77 g cm -3, respectively. The calculated densities of the other compounds range between 1.61 and 1.98 g cm-3. The detonation velocity (D) values calculated for these synthesized compounds range from 5.45 to 8.06 km s-1, and the detonation pressure (P) ranges from 12.35 to 28 GPa.
Making endo-cyclizations favorable again: A conceptually new synthetic approach to benzotriazoles via azide group directed lithiation/cyclization of 2-azidoaryl bromides
Ageshina, Alexandra A.,Chesnokov, Gleb A.,Topchiy, Maxim A.,Alabugin, Igor V.,Nechaev, Mikhail S.,Asachenko, Andrey F.
, p. 4523 - 4534 (2019/05/17)
Although benzotriazoles are important and ubiquitous, currently there is only one conceptual approach to their synthesis: bridging the two ortho-amino groups with an electrophilic nitrogen atom. Herein, we disclose a new practical alternative-the endo-cyclization of 2-azidoaryl lithiums obtained in situ from 2-azido-aryl bromides. The scope of the reaction is illustrated using twenty-four examples with a variety of alkyl, alkoxy, perfluoroalkyl, and halogen substituents. We found that the directing effect of the azide group allows selective metal-halogen exchange in aryl azides containing several bromine atoms. Furthermore, (2-bromophenyl)diazomethane undergoes similar cyclization to give an indazole. Thus, cyclizations of aryl lithiums containing an ortho-X = Y = Z group emerge as a new general approach for the synthesis of aromatic heterocycles. DFT computations suggested that the observed endo-selectivity applies to the anionic cyclizations of other functionalities that undergo "1,1-additions" (i.e., azides, diazo compounds, and isonitriles). In contrast, cyclizations with the heteroatomic functionalities that follow the "1,2-addition" pattern (cyanates, thiocyanates, isocyanates, isothiocyanates, and nitriles) prefer the exo-cyclization path. Hence, such reactions expand the current understanding of stereoelectronic factors in anionic cyclizations.
Does the partial molar volume of a solute reflect the free energy of hydrophobic solvation?
Szymaniec-Rutkowska, Anna,Bugajska, Ewa,Kasperowicz, S?awomir,Mieczkowska, Kinga,Maciejewska, Agnieszka M.,Poznański, Jaros?aw
, (2019/08/26)
Halogenated heterocyclic ligands are widely used as the potent and frequently selective inhibitors of protein kinases. However, the exact contribution of the hydrophobic solvation of a free ligand is rarely accounted for the balance of interactions contributing to the free energy of ligand binding. Herein, we propose a new experimental method based on volumetric data to estimate the hydrophobicity of a ligand. We have tested this approach for a series of ten variously halogenated benzotriazoles, the binding affinity of which to the target protein kinase CK2 was assessed with the use of thermal shift assay. According to the hierarchical clustering procedure, the excess volume, defined as the difference between the experimentally determined partial molar volume and the calculated in silico molecular volume, was found to be distant from any commonly used hydrophobicity descriptors of the ligand. The excess volume, however, properly predicts solute binding affinity. On the way, we have proved that the binding of halogenated benzotriazoles to the protein kinase CK2 is driven mostly by hydrophobic interactions.
