Synthesis of Two Mononuclear Schiff Base Metal (M = Fe, Cu) Complexes: MOF Structure, Dye Degradation, H₂O₂ Sensing, and DNA Binding Property

Abstract

O-Vanillin and ethylenediamine were used for the synthesis of N,N′-bis(O-vanillinidene)ethylenediamine (O-VEDH2) Schiff base ligand, which was characterized by UV–visible and 1H NMR spectroscopy. The Schiff base ligand O-VEDH2 has been employed to synthesize novel [C18H22FeN2O6]NO3 (1) and C18H16CuN2O5 (2) complexes by the simple slow evaporation method. The single crystals were characterized by X-ray crystallography, as well as Fourier-transform infrared and UV–visible spectroscopy techniques. Complexes 1 and 2 crystallize in monoclinic and orthorhombic space groups with P121/n1 (14) and Pnma (62) point groups, respectively, and both show metal–organic frameworks like structures. Complexes 1 and 2 have optical band gaps of 4.1 and 2.9 eV, respectively, indicating their semiconducting properties. The dye degradation activity and H2O2 sensing of the complexes 1 and 2 were determined in different conditions. The photocatalytic test was performed in the presence of sunlight, methylene blue (MB), and complexes 1 and 2. An interesting result was obtained that complex 2 has degradation ability against MB and the rate constant (K) is 5.46 × 10–5 s–1, whereas complex 1 has H2O2 sensing properties. Both complexes are bound to Calf-thymus DNA by intercalation binding mode, and binding constants (Kb) of complexes 1 and 2 are 3.77 × 103 and 1.49 × 104 M–1, respectively.

Green synthesis of copper nanoparticles using leaf extract of Ageratum houstonianum Mill. and study of their photocatalytic and antibacterial activities

“…Therefore, the biosynthesized AH-CuNPs may act as a stable and efficient green catalyst for the degradation of CR under sunlight. The electrons of AH-CuNPs were easily transitioned from Valence Band (VB) to Conduction Band (CV) in presence of sunlight, and degrade the CR with the degradation product as shown in figure 8(a) [64]. ESI-I indicates the possible mechanism for dye degradation by AH-CuNPs against CR.…”

The synthesis of a Cu(ii) Schiff base complex using a bidentate N2O2 donor ligand: crystal structure, photophysical properties, and antibacterial activities

“…9). The HOMO and LUMO energy levels of the HL ligand and the Cu(II) complex can be estimated from the onset oxidation potential (E onset ) and E ferrocene as follows: [38][39][40] HOMO The results are listed in Table 2. The HOMO and LUMO energy levels and the energy gap of the Cu(II) complex are lower than those of the HL ligand, and this indicates that the corresponding electron transition from HOMO to LUMO for the Cu(II) complex is easier than that for the HL ligand.…”

Data_Sheet_2.PDF

“…The Schiff base ligand N,N ′ -bis(o-vanillinidene) ethylenediamine (o-VEDH 2 ) was synthesized in the following procedure (Scheme 1) and also reported in our earlier publication (Ghosh et al, 2019b):…”

“…The H 2 O 2 detection protocol is already discussed in our previous article (Bera and Raj, 2013;Ghosh et al, 2019b). Initially, complexes were dissolved in CH 3 CN to obtain a suitable dilute solution for the initial of UV-visible spectrum.…”

“…and its purity was confirmed from the obtained absorbance ratio of A260/A280 in the range of 1.8 to 1.9. (Ghosh et al, 2019b).…”