QUANTUM-CHEMICAL AND EXPERIMENTAL STUDY OF NUCLEOPHILIC SUBSTITUTION REACTIONS OF N-ALKYL-3-NITRO-1,2,4-TRIAZOLES
Abstract
Reactions of nucleophilic substitution of nitro group in N-alkyl-3-nitro-1,2,4-triazoles have been studied both experimentally and theoretically using DFT method. The standard enthalphy and Gibbs free energy of alkoxylation reactions of N-alkyl-3-nitro-1,2,4-triazoles in gas phase and aqueous solution have been calculated. The calculation results show that nucleophilic substitution reactions of N-alkyl-3-nitro-1,2,4-triazoles with alcohols and alcoholate anions are thermodynamically possible both in gas phase and in aqueous solution. Computed activation energies for reactions of N-alkyl-3-nitro-1,2,4-triazoles with methanol decrease in the series of ΔG≠S(for 1-isomer) >> ΔG≠S(for 4-isomer) > ΔG≠S(for 2-isomer). The calculation results are in good agreement with experimental data.