Papers by Keyword: Schiff-Base

Abstract: Used seven different aldehyde besides salicylaldehyde, respectively, reacted with the amino acid in the ethanol ratio of 1:1 has prepared seven Schiff base;then used 2(2(4-chlorobenzeneyl) methyl)tin and 2(4-on cyanoacrylate benzylidene)2 chloride tin reacted with above seven Schiff base in anhydrous ethanol, has prepared a series of new organo tin (IV) Schiff base complexes . The synthesis process was used the new technology of microwave and all the compounds were characterized.

Abstract: Some functional Schiff base derivatives with azobenzene substituted groups have been designed and synthesized from the reaction of aminoazobenzene with different aromatic aldehydes. It has been found that depending on the size of aromatic groups, the formed Schiff base derivatives showed different properties, indicating distinct regulation of molecular skeletons. UV and IR data confirmed commonly the formation of Schiff base as well as aromatic segment in molecular structures. Thermal analysis showed that the thermal stability of Schiff base molecules with naphthalene segment increased slightly in comparison with other derivatives. The difference of thermal stability is mainly attributed to the formation of Schiff base group and aromatic substituent groups in molecular structure. The present results have demonstrated that the special properties of Schiff base derivatives can be turned by modifying molecular structures of objective compounds with proper substituted groups, which show potential application in functional material field.

Abstract: In order to investigate the supramolecular assembly and intermolecular hydrogen bonding of special amphiphiles, two bolaform amphiphilic Schiff bases (GN1 and GN2) with different hydrophilic spacers were designed, and their supramolecular assembly and interaction properties were investigated by spectral measurements. It was found that both the Schiff bases showed hydrogen bonding interaction with barbituric acid. In addition, it was interesting to note that the spacer groups of the molecules had effect on the molecular ratio in the hydrogen-bonded complexes. Due to the directionality and strong matching of hydrogen bond, one barbituric acid molecule can be encapsulated into the intramolecular area of GN1, while two barbituric acid molecules were trapped into the GN2 molecule through intermolecular H-bonds for GN2 due to the long spacer and flexible structure. A rational complex mode was proposed.

Abstract: A novel synthesis method on solvent-free reaction using improved jet milling was described. Synthesis of a schiff base derived from p-hydroxybenzaldehyde and p-aminobenzoic acid had been achieved by solvent-free reaction using improved jet milling, and the structure of the compound have been characterized by Fourier transform infrared spectrometer, 1H nuclear magnetic resonance techniques and mass spectrometry. Differential thermal analysis of reaction process shown that the reaction was complete within 6 min. The scanning electron microscopy shown that the particles of the schiff base were regular and the size of the most particles was 0.5~1 μm. At the same time, the theoretical analysis about reaction process of solvent-free reaction using improved jet milling was preliminary studied. This solvent-free reaction using improved jet milling not only involves mild conditions, a simple operation and short reaction time, but also gives quantitative yield without waste producing work-up procedures. Simultaneously, the investigation also showed this reaction method was feasible, and of benefit to environment.

Abstract: The Self-assembled monolayers (SAMs) of Schiff base had been formed on oxidized surfaces of copper. Schiff base used in this paper is N-2-hydroxyphenyl- (3-methoxy-salicylidenimine), designated V-bso. X-ray photoelectron spectroscopy (XPS), polarization curves, electrochemistry impedance spectroscopy (EIS) and the interface capacitance measurements have been employed to investigate the structure, formation and composition of these monolayers. XPS analysis show that the valence of the copper in the surface films is +2. The polarization curves and the EIS results indicate that the films of CuO, V-bso, and V-bso modified oxidized copper all have good corrosion inhibition efficiency. The IE of the V-bso modified oxidized copper is higher than that of the V-bso modified copper and the oxidized copper layer, just because the former has two layers. The results of the interface capacitance show that the self-assemble films of the V-bso on the oxidized copper surface have good potential stability.

Abstract: As a result of the Schiff base condensation the gadolinium macroacyclic and macrobicyclic Schiff base complexes have been synthesized and investigated by infrared spectroscopy (IR) and electron paramagnetic resonance (EPR). Both electron ionization and electron spray Molecular Spectroscopy spectra confirmed the [1:1] proportion of a ligand to metal in gadolinium macrocyclic and mocrobicyclic Schiff base complex samples. The thermogravimetrydifferential thermal analysis (TG-DTA) indicated the presence of two water molecules in the innersphere of the macrobicyclic complex and confirmed no water coordination of the metal ion in the macroacyclic complex. The temperature dependence of the integrated intensity of the EPR spectra enabled the magnetic interactions in the spin system of these compounds to be revealed.