One Pot Synthesis, Characterization, DFT Studies and AIM Analyses of Ethyl-1-aryl-1H-tetrazole-5-carboxylate

Abstract

A new series of bis/mono ethyl-1-aryl-1H-tetrazole-5-carboxylate has been synthesized by treating respective tetrazole with ethyl chloroformate in THF and DIPEA as a catalyst. The structure of the novel molecule is characterized by FT-IR, 1H-NMR, 13C-NMR, and mass spectra. After conforming the structure, bis/mono ethyl-1-aryl-1H-tetrazole-5-carboxylate was subjected to hydrolysis under both acidic and basic conditions. The hydrolysis reaction did not occur; to know the relevant reason, we move to theoretical studies. DFT B3LYP method was used to determine the optimized structure and HOMO & LUMO energies of the title molecule. The energy was found to be from 4.23-5.31 eV. Energy gap was related to hardness and reactivity. Additionally, we provide the reason with respect to AIM analysis, which was performed for one molecule. The synthesized title molecules were characterized by IR, 1H & 13C NMR, mass and elemental analysis. Theoretical studies such as DFT and AIM analysis were also performed. All the synthesized compounds were verified by analytical data such as IR, NMR, elemental analysis, mass spectra and theoretical studies such as DFT and AIM analysis. The HOMO & LUMO energy was found to be from 4.5 eV to 5.2 eV. More energy gap results in enriched hardness in the molecule and decreased reactivity. From the AIM analysis result, we found that there is a formation of a weak bond between the oxygen of the carbonyl group and carbon of the phenyl group. Due to these reasons, the title molecule did not undergo hydrolysis reaction under both acidic and basic conditions. We report on the synthesis and characterization of bis/mono ethyl-1-aryl-1H-tetrazole-5- carboxylate. HOMO & LUMO energy were found to be 4.5 – 5.2 eV. High energy will increase the hardness of the molecule which will result in decreased reactivity of the molecule. Additionally, we provide AIM analysis done for the compound 6a and there is formation of a weak bond between the oxygen of the carbonyl group and carbon of the phenyl group. Oxygen used its lone pair of electron in the formation of a weak bond with carbon and hence oxygen become unreactive and so the hydrolysis reaction did not happen.