Synthesis, structural and computational studies of new tetrazole derivatives

Herein, we report a synthesis of two new disubstituted tetrazoles, 2-(2,4-dinitrophenyl)-5-methyl-2H-tetrazole (2) and 1-(2,4-dinitrophenyl)-5-methyl-1H-tetrazole (3). The products were characterized by H-1 and C-13 NMR spectroscopy, as well as single-crystal X-ray diffraction. The intermolecular interactions in the crystals were investigated by Hirshfeld surface analysis, 2D fingerprint plots, and noncovalent interaction analysis (NCI). Tetrazole rings of both compounds were found to be involved in both strongest attractive and repulsive intermolecular interactions. DFT calculations were performed using the PW6B95-D3(BJ)/def2-TZVP level of theory in order to obtain information about the molecular electrostatic potential (MEP), and global and local reactivity (dual descriptor) indices of the studied tetrazoles. The calculated molecular electrostatic potentials correlated well with the Hirshfeld surface and NCI plots. The 1,5-disubstituted tetrazole exhibited lower kinetic stability and was slightly more electrophilic than the 2,5-regioisomer. The dual descriptor index was used to reveal electrophilic and nucleophilic sites for both molecules. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

A synthesis of two new disubstituted tetrazoles was reported, characterized by various analysis methods. Both tetrazole rings were found to be involved in the strongest intermolecular interactions in the crystals. The molecular electrostatic potentials correlated well with the Hirshfeld surface and NCI plots, revealing differences in stability and reactivity between the two regioisomers.