The Schiff bases H₃dfmp(L)₂ obtained by the condensation of 2,6-diformyl-4-methylphenol and hydrazones [L = isonicotinoylhydrazide (inh), nicotinoylhydrazide (nah) and benzoylhydrazide (bhz)] are prepared and characterized. By reaction of [V^IVO(acac)₂] and the H₃dfmp(L)₂ in methanol the V^IVO-complexes [V^IVO{Hdfmp(inh)₂}(H₂O)] (1), [V^IVO{Hdfmp(nah)₂}(H₂O)] (2) and [V^IVO{Hdfmp(bhz)₂}(H₂O)] (3) were obtained. Upon their aerial oxidation in methanol [V^VO(OMe)(MeOH){Hdfmp(inh)₂}] (4), [V^VO(OMe)(MeOH){Hdfmp(nah)₂}] (5) and [V^VO(OMe)(MeOH){Hdfmp(bhz)₂}] (6) were isolated. In the presence of KOH, oxidation of 1–3 results in the formation of [V^VO₂{H₂dfmp(inh)₂}]_n·5H₂O (7), K[V^VO₂{Hdfmp(nah)₂}] (8) and K[V^VO₂{Hdfmp(bhz)₂}] (9). All compounds are characterized in the solid state and in solution, namely by spectroscopic techniques (IR, UV-Vis, EPR, ¹H, ¹³C and ⁵¹V NMR), and DFT is also used to calculate the V^IV hyperfine coupling constants of V^IV-compounds and ⁵¹V NMR chemical shifts of several V^V-species and assign them to those formed in solution. Single crystal X-ray analysis of [V^VO(OMe)(MeOH){Hdfmp(bhz)₂}] (6) and [V^VO₂{H₂dfmp(inh)₂}]_n·5H₂O (7) confirm the coordination of the ligand in the dianionic (ONO²⁻) enolate tautomeric form, one of the hydrazide moieties remaining non-coordinated. In the case of 7 the free N(pyridine) atom of the inh moiety coordinates to the other vanadium center yielding a polynuclear complex in the solid state. It is also demonstrated that the V^VO₂-complexes are catalyst precursors in the oxidative bromination of styrene by H₂O₂, therefore acting as functional models of vanadium dependent haloperoxidases. Plausible intermediates involved in the catalytic process are established by UV-Vis, ⁵¹V NMR and DFT studies.

An eco-friendly magnetic mesoporous silica iron oxide (MS@Fe ₃ O ₄ ) nanoparticles with a high surface area was fabricated using a colloidal chemical method.

The florescent carbon dot conjugated chitosan nanoparticles are developed for the cellular imaging and delivery of poorly water soluble drug telmisartan (TEL).

Two monomeric copper complexes [Cu^II(sal-ppzH)Cl₂] (1) and [Cu^II(hyap-ppzH)Cl₂] (2) were synthesized by reacting CuCl₂·2H₂O with the monobasic tridentate Schiff-base ligands [Hsal-ppz] (I) and [Hyap-ppz] (II) (derived by reacting 1-(2-aminoethyl) piperazine with salicylaldehyde and 2-hydroxyacetophenone) respectively. Elemental analysis, IR, UV-Vis, ¹H NMR and ¹³C NMR data confirm the structures of the ligands and those of the complexes. Both complexes are monomeric in nature in the solid state and in solution as well. Single crystal XRD data suggest a distorted square pyramidal geometry for 1 crystallized in the P space group. DFT studies established a similar molecular structure for 2. The synthesized metal complexes [Cu^II(sal-ppzH)Cl₂] (1) and [Cu^II(hyap-ppzH)Cl₂] (2) successfully catalyzed the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC) in methanol in the presence of H₂O₂ with high K_cat values of 1.182 × 10⁴ mmol h⁻¹ and 2.880 × 10⁴ mmol h⁻¹, respectively. [Cu^II(sal-ppzH)Cl₂] (1) and [Cu^II(hyap-ppzH)Cl₂] (2) were also anchored into the polymeric matrix of chloromethylated polystyrene and were analyzed by TGA, atomic absorption spectroscopy (AAS), EPR, scanning electron microscopy (SEM) as well as energy dispersive X-ray (EDX) analysis. The polymer grafted metal complexes were used as catalyst precursors in the oxidative bromination of salicylaldehyde in the presence of H₂O₂, KBr and HClO₄. Under optimized reaction conditions, both catalysts show nearly quantitative oxidative bromination of salicylaldehyde, with the order of % products formed being 5-bromosalicylaldehyde > 3,5-dibromosalicylaldehyde > 3-bromosalicylaldehyde. Plausible reactive species involved in the catalytic cycle are identified by UV-Vis spectroscopy, pH metric titration, ESI-MS, EPR and DFT studies.