Quantum chemical studies of azoles 8. Effect of N(2)-methyl substituent on the calculated thermodynamic parameters of electrophilic substitution in tetrazole according to the elimination–addition scheme without preceding formation of N-protonated azolium salts

Thermodynamic characteristics of electrophilic substitution reactions of 2-methyltetrazole and 2H-tetrazole proceeding according to the elimination–addition pathway (with the HO– anion and hydroxonium ion as model agents) were compared on the basis of analysis of the results obtained by quantum chemical calculation performed using the DFT/B3LYP/6-31G(d,p) method and taking account of the specific solvation effects. Comparison with previous results for 1-methyltetrazole obtained by the same authors using the same method revealed probable reasons for the known lack of ability of 2-methyltetrazole to undergo electrophilic substitution reactions, particularly, the substantially lower polarity and HOMO and LUMO energies, that is, higher Mulliken electronegativity of 2-methyltetrazole compared with the 1-isomer.