Formation of polymeric chain assemblies of transition metal complexes with a multidentate Schiff-base

Abstract

The new multidentate Schiff-base (E)-6, 6 0 -((1E,1 0 E)-(ethane-1,2-diylbis(azan-1-yl-1-ylidene))bis-(methan-1-yl-ylidene))bis(4-methyl-2-((E)(pyridine-2-ylmethylimino)methyl)phenol) H 2 L and its polymeric binuclear metal complexes with Cr(III), Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) are reported. The reaction of 2,6-diformyl-4-methyl-phenol with ethylenediamine in mole ratios of 2:1 gave the precursor 3,3 0 -(1E,1 0 E)-(ethane-1,2-diylbis(azan-1-yl-1ylidene))bis-(methan-1-yl-1-ylidene)bis(2-hydroxy-5-methylbenzaldehyde) W. Condensation of the precursor with 2-(amino-methyl)-pyridine in mole ratios of 1:2 gave the new N 6 O 2 multidentate Schiff-base ligand H 2 L. Upon complex formation, the ligand behaves as a dibasic octadentate species with the involvement of the nitrogen atoms of the pyridine groups in coordination for all complexes. The mode of bonding and overall geometry of the complexes were determined through physico-chemical and spectroscopic methods. These studies revealed octahedral geometries for Cr(III),

N,N′-Dipyridoxyl(1,8-diamino-3,6-dioxaoctane) Schiff-base: Synthesis, experimental and theoretical identification

“…For comparison, some structural parameters of the similar compounds are listed in Table 1. The DFT structural parameters of H 2 L are in agreement with the structural data reported for the similar Schiff-bases [1,2,[10][11][12][13][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40], confirming validity of the optimized geometry for the H 2 L Schiff-base. The optimized geometry of the H 2 L with atom labelling is shown in Figure 1.…”

Metal Complexes of Macrocyclic Schiff‐Base Ligand: Preparation, Characterisation, and Biological Activity

“…The doublet at 7.3 ppm is assigned to protons of aromatic rings. The appearance of these protons as a doublet is due to mutual coupling and/or a fluctuation behaviour generated by (–CH 2 CH 2 –) moieties [15]. In general, the spectrum showed broader peaks compared with that for the free ligand.…”

“…The magnetic moment values for the tetranuclear macrocyclic complexes at RT are lower than the predicted values, indicating the presence of some antiferromagnetic interactions. This may occur from metal-metal interactions through the phenolic oxygen atoms and/or extensive electron delocalisation, which may be related to the formation of layer structures [15, 19, 33]. …”

“…The resulting solution was refluxed for 30 min, and on treatment with distilled water (400 mL), a light orange precipitate was formed, which was stored overnight at 4°C. The orange product was isolated by filtration and washed in small amount of cold methanol to obtain 2,4,6-triformyl phenol (tfp) [15]. The yielded product (TFP) (59%, 10.5 g) was mixed with equimolar amounts of NaOH (2.35 g, 5.8 mmol) in ethanol (25 mL).…”

Effects of Potential Modes on Performances of Electrodeposited Poly[Ni(salen)]/MWCNTs Composite as Supercapacitor Electrode Material

“…17 The bands in the range of 3000-2835 cm ¹1 is assigned to CH 2 , and the appearance of protons as a doublet is due to mutual coupling or a fluctuation behavior generated by (-CH 2 H 2 C-) moieties. 18 Moreover, the C=N imine stretching band is observed at around 1632 cm…”