X-ray Single Crystal Structure, Tautomerism Aspect, DFT, NBO, and Hirshfeld Surface Analysis of a New Schiff Bases Based on 4-Amino-5-Indol-2-yl-1,2,4-Triazole-3-Thione Hybrid

Four different new Schiff basses tethered indolyl-triazole-3-thione hybrid were designed and synthesized. X-ray single crystal structure, tautomerism, DFT, NBO Hirshfeld analysis explored. crystallographic investigations with the aid of calculations used to analyze molecular packing studied systems. The H···H, H···C, S···H, Br···C, O···H, C···C N···H interactions are most important in 3. In case 4, N···H, S···C contacts significant. results obtained from DFT indicated that thione tautomer is energetically lower than thiol one by 13.9545 13.7464 kcal/mol for 3 respectively. Hence, stable which agree reported structure. addition, compute electronic properties while natural bond orbital predict stabilization energies due conjugation effects. Both compounds polar where 4 (3.348 Debye) has a higher dipole moment (2.430 Debye).