Akademik Veri Yönetim Sistemi
Journal of Molecular Structure, cilt.1352, 2026 (SCI-Expanded)
Six novel dioxomolybdenum(VI) complexes of 2-hydroxy-5-chloro/methoxy benzlidene-S-allyl-N-phenyl/cyclohexyl/hexyl substituted thiosemicarbazones were synthesized and characterized by analytical and spectroscopic techniques. As a representative example, the molecular structure of complex 4 named cis-dioxo-(N1-2-hydroxy-5-methoxybenzylidene-N4-phenyl thiosemicarbazonato)-methanol-molybdenum(VI) was studied by single-crystal X-ray diffraction, revealing a distorted octahedral environment of the molybdenum center. The antioxidant activities of the synthesized compounds were evaluated using the cupric ion reducing antioxidant capacity (CUPRAC) assay, while cyclic voltammetry (CV) was employed to investigate their redox behaviour and its relationship to antioxidant capacity; in addition, the effects of different substitutions on activity were systematically compared. The presence of a methoxy substituent at the 5-position of the aromatic ring showed higher antioxidant activity compared to chloro substitution. The photophysical behaviours of the complexes were investigated by UV–visible absorption and fluorescence emission spectroscopy in different solvents. Additionally, thermogravimetric analysis (TGA) was conducted to assess thermal stability. DFT and TD-DFT calculations on complex 4, selected as a representative example, supported the experimental findings and clarified both absorption/emission properties and solvent-dependent photophysical behavior.