Synthesis, Spectroscopic Characterization, and Thermal Behavior Studies of 2-Anilino-N-[(1E)-(2-Hydroxyphenyl)Methylene] Acetohydrazide Metal Complexes

Abstract

Novel complexes of Ru(III), Pd(II), Th(IV), UO₂(VI), and Sn(IV) of 2-anilino-N[(1E)(2-hydroxyphenyl)methylene] acetohydrazide (H₂L) have been synthesized and characterized by elemental analyses, spectral (FT-IR, ¹H NMR, and MS) studies, molar conductivity measurements, and thermal analysis (DTA/TG) techniques. Spectral studies show that the ligand displays different coordination mode with metal ions. Thermal studies reveal that Pd(II) complex has higher thermal stability than UO₂(VI), Sn(IV), Th(IV), and Ru(III) complexes. The kinetic and thermodynamic activation parameters of decomposition processes of metal complexes, namely activation energy (E*), enthalpy (ΔH*), entropy (ΔS*), and Gibbs free energy (ΔG*), were evaluated graphically from TG curve by employing the Coats–Redfern relation.

Keywords:

• complexes
• ¹H NMR
• kinetic and thermodynamic activation parameters
• thermal analysis (DTA/TG)