Inductive Effect of Bioactive Intermolecular Hydrogen Bonding Complex of 1,2,4,5 –Tetrazine and Inorganic Acid by NMR and QTAIM

In this paper, NMR and QTAIM analysis for three substituted of T2SA complex was investigated in the gas and four solvents at DFT level. Intermolecular O–H…N hydrogen bonds between 1,2,4,5-Tetrazine and Sulphurous acids enhance the stability of complex.1,2,4,5-Tetrazine is a highly reactive diene for [4+2] inverse-Diels–Alder cycloaddition processes and an excellent precursor to attain the pyridazine ring. 1,2,4,5-Tetrazines have been very widely utilized for the highly effective synthesis of natural products, bioactive compounds and ligands. The comparison between the donor and attractive group on hydrogen bonding intermolecular systems is discussed. The deshielding effects on hydrogen nucleus of this compound in solvents are referred to intermolecular hydrogen bonds which are controlled by dielectric constants. Dielectric constant increased the hydrogen atoms are deshielded, in the DMSO and water, the changes is small, because in theses polarity of solvent is very high. When donor group is substituted in this complex electron density is increased. The QTAIM results show that in the DMSO and water, the changes is small, because in theses polarity of solvent is very high. The NMR and QTAIM results are harmonious together in all cases. All calculations were performed using B3LYP method and 6-311++G** basis set in GAUSSIAN09W and AIM2000 programs.