DFT-BASED INVESTIGATION OF TAUTOMERIC TRANSITION IN AN ORGANIC MOLECULE: TRANSITION STATE AND ELECTRONIC STRUCTURE ANALYSIS

Yıl 2025, Cilt: 1 Sayı: 1, 1 - 10, 26.12.2025

Tuncay Karakurt

https://izlik.org/JA84WW95NN

Öz

The molecular structure of 3-(p-chlorobenzyl)-4-(pfluorobenzylideneamino)-4,5-dihydro-1H-1,2,4-triazol-5-one,
previously determined by single-crystal X-ray diffraction, exhibits
characteristic features suitable for tautomeric isomerism. In this study, two
possible tautomeric forms of the compound were optimized in the gas phase
using density functional theory (DFT) at the B3LYP/6-31G(d) level. To
explore the potential energy surface between the two structures and confirm the nature of the transition state, Intrinsic Reaction Coordinate (IRC)
calculations were performed. Theoretical results reveal a distinct energy
difference, demonstrating that one tautomer is considerably more stable in
the gas phase compared to the alternative form. Structural parameters, bond
lengths, and dihedral angles were carefully examined to highlight the
geometrical changes associated with the tautomerization process. This
theoretical investigation provides valuable insights into the tautomeric
behavior of triazole-based systems and complements previous
crystallographic findings. Moreover, the results underline the importance of
integrating experimental and theoretical approaches to obtain a deeper
understanding of structure–property relationships in heterocyclic
compounds.

Anahtar Kelimeler

İzomerizm , DFT , IRC

Kaynakça

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