886-34-0Relevant academic research and scientific papers
A novel water-dispersible and magnetically recyclable nickel nanoparticles for the one-pot reduction-Schiff base condensation of nitroarenes in pure water
Ghamari Kargar, Pouya,Ravanjamjah, Asiye,Bagherzade, Ghodsieh
, p. 1916 - 1933 (2021/07/10)
In this work, a heterogeneous nanocatalyst called Ni-Fe3O4@Pectin~PPA ~ Piconal was first synthesized, which was investigated as a bifunctional catalyst containing nickel functional groups. On the other hand, this Ni-Fe3O4@Pectin~PPA ~ Piconal catalyst in aqueous solvents shows a very effective performance at ambient temperature for the nitroarene reduction reaction with sodium borohydride, for which NaBH4 is considered as a reducing agent. This is a novelty magnetic catalyst that was approved by various methods, including Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), Dynamic light scattering (DLS), Transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), Inductively coupled plasma (ICP), Energy-dispersive X-ray spectroscopy (EDX), and Field emission scanning electron microscopy (FESEM) analyses. From the satisfactory results obtained from the reduction of nitrogen, this catalytic system is used for a one-pot protocol containing a reduction-Schiff base concentration of diverse nitroarenes. It was corroborated with the heterogeneous catalytic experiments on the one-pot tandem synthesis of imines from nitroarenes and aldehydes. Finally, the novel Ni-Fe3O4@Pectin~PPA ~ Piconal catalyst could function as a more economically desirable and environmentally amicable in the catalysis field. The favorable products are acquired in good to high performance in the attendance of Ni-Fe3O4@Pectin~PPA ~ Piconal as a bifunctional catalyst. This catalyst can be recycled up to six steps without losing a sharp drop.
Simple synthesis of the novel Cu-MOF catalysts for the selective alcohol oxidation and the oxidative cross-coupling of amines and alcohols
Ghamari Kargar, Pouya,Aryanejad, Sima,Bagherzade, Ghodsieh
, (2020/09/11)
A novel porous metal–organic framework {Cu2(bbda)0.5(Hbbda)1.5(OAc)1.5.8H2O} (UoB-5) was synthesized under ultrasound irradiation by employing a new Schiff base ligand H2bbda (4,4'(1,4-phenylene bis (azanylylidene)) bis (methanylylidene))dibenzoic acid) and was fully characterized. The microporous nature of UoB-5 was confirmed by gas-sorption measurements. This framework acted as a highly effective heterogeneous catalyst for the alcohol oxidation reaction with tert-butyl hydroperoxide (t-BuOOH) as an oxidant. The presence of coordinatively unsaturated metal sites in UoB-5 could be the reason for high performance in this reaction. Furthermore, using the long linker with the free -NC group and uncoordinated -N atom on the wall of the pores created UoB-5 an excellent candidate for the catalytic activities without activation of the framework. It was confirmed with the heterogeneous catalytic experiments on the one-pot tandem synthesis of imines from benzyl alcohols and anilines. Eventually, the new Cu-MOF (UoB-5) could be an alternative catalyst as a more economically favorable and environmentally friendly in the catalysis field.
Influence of substituents on the structure of Schiff bases Cu(II) complexes
Xiao, Yan,Cao, Chenzhong
, (2020/02/29)
The relationship between molecular conformation and substituent effects of salicylaldehyde Schiff-base Cu(II) complexes was explored. For this study, eight samples of the complexes Cu(Sal-X)2 (X = OMe, Me, H, F, Cl, Br, CF3 and CN) w
Synthesis, spectroscopic characterization and computational studies of Schiff base complexes of tin(IV) chloride
Jaiswal, Nitesh,Kushwaha, Ajeet Kumar,Singh, Avadhesh Pratap,Dubey, Raj Kumar
, p. 28 - 36 (2019/06/24)
Reaction of anhydrous tin(IV) chloride with mono functional bidentate Schiff bases (sbnH), in 1:2 molar ratios, gives complexes of the type, [(sbn)2SnCl2] (1-4) (where, n=1-4; sb=2-(((4-chlorophenyl)imino)methyl
Effect of substituents on the UV spectra of supermolecular system: Silver nanoparticles with bi-aryl Schiff bases containing hydroxyl
Cao, Chao-Tun,Cheng, Shimao,Zhang, Jingyuan,Cao, Chenzhong
, (2018/11/25)
Effect of substituents on the ultraviolet (UV) spectra of supermolecular system involving silver nanoparticles (AgNPs) and Schiff bases was investigated. AgNPs and 49 samples of model compounds (MC), bi-aryl Schiff bases containing hydroxyl (XBAY, involving 4-OHArCH?NArY, 2-OHArCH?NArY, XArCH?NAr-4′-OH, and XArCH?NAr-2′-OH), were synthesized. The size of AgNPs was characterized by transmission electron microscopy (TEM), and the UV absorption spectra of AgNPs, XBAYs, and MC-AgNPs mixed solutions were measured, respectively. The results show that (1) the size of AgNPs is larger in MC-AgNPs solutions than that in AgNPs solution due to the distribution of MC molecules on the surface of AgNPs; (2) the UV absorption wavelength of XBAYs changes in the action of AgNPs and their wavelength shift exists limitation between XBAY and MC-AgNPs solutions; and (3) the wavelength shift limit of MC-AgNPs (λWSL) is influenced by the substituents X and Y and the position of hydroxyl OH. The wavenumber ΔνWSL of λWSL can be quantified by employing the excited-state substituent constant σexCC and Hammett constant σ of substituents X and Y. Comparing with the 4-OH, the 4′-OH makes the ΔνWSL a red shift, whereas the 2′-OH, comparing with the 2-OH, makes the ΔνWSL a blue shift.
Copper-Catalyzed Asymmetric Annulation Reactions of Carbenes with 2-Iminyl- or 2-Acyl-Substituted Phenols: Convenient Access to Enantioenriched 2,3-Dihydrobenzofurans
Liang, Xin-Shen,Li, Rui-Dong,Wang, Xiao-Chen
supporting information, p. 13885 - 13889 (2019/08/26)
We have developed a method for the highly diastereo- and enantioselective construction of 2,3-dihydrobenzofurans bearing tetrasubstituted carbon stereocenters by means of annulation reactions between carbenes and 2-iminyl- or 2-acyl-substituted phenols through catalysis by readily accessible copper(I)/bisoxazoline catalysts under mild conditions. These reactions feature a unique mechanism in which the copper catalyst serves a dual function: first it reacts with the diazo compound to generate a metal carbene, and second, upon formation of an oxonium ylide, it acts as a Lewis acid to activate the imine or ketone for diastereo- and enantioselective cyclization.
Substituent effects on the absorption and vibrational spectra of some 2-hydroxy Schiff bases: DFT/TDDFT, natural bond orbital and experimental study
Elroby,Aboud,Aziz,Hilal
, p. 414 - 427 (2015/08/06)
The electronic structure of salicylideneaniline (SA) and some of its derivatives are investigated both experimentally and theoretically. The equilibrium geometric structures of the studied compounds are determined at the B3LYP/6-311++Glevel of theory. A set of 12 substituted SA derivatives is considered in the present work. The choice of these substituents aims to create a push-pull system on the SA basic structure which would shade light onto its photo physics. The electronic absorption spectra of SA are recorded in the UV-VIS region, in both polar and nonpolar solvents. Assignments of the observed electronic transitions are facilitated via time-dependent density functional theory (TDDFT) computations at the same level of theory. Electronic configurations contributing to each excited state are identified and the relevant MOs are characterized. The extent of delocalization and intramolecular charge transfer are estimated and discussed in terms of natural bond orbitals (NBO) analysis and second order perturbation interactions between donor and acceptor MOs. Solvent effects on the electronic absorption spectra are discussed in terms of the difference in polarizabilities of the ground and excited states. FTIR spectra of SA and its derivatives are measured in KBr platelets. Detailed vibrational assignments are given based on the calculated potential energy distributions. "IR marker bands" that characterize the SA framework are identified. The effect of substituents, the nature of the characteristic "marker bands", and intensity quenching of some bands are discussed.
Synthesis and distinct urease enzyme inhibitory activities of metal complexes of Schiff-base ligands: Kinetic and thermodynamic parameters evaluation from TG-DTA analysis
Ikram, Muhammad,Rehman, Sadia,Faridoon,Baker, Robert J.,Rehman, Hanif Ur,Khan, Ajmal,Choudhary, Muhammad Iqbal,-Rehman, Saeed-Ur
, p. 72 - 80 (2013/04/23)
Transition metal [Co, Ni, Cu and Zn(II) acetates] complexes of salicylaldehyde derived Schiff bases, 2-{(E)-[(4-chlorophenyl)imino]methyl} phenol (CIMP) and 2-{(E)-[(4-bromophenyl)imino]methyl}phenol (BIMP) were synthesized and characterized by various analytical and spectroscopic studies. The Schiff base ligands and their metal complexes were also screened for their urease, α-chymotrypsin, acetylcholinesterse and butyrylcholinesterase inhibition activities. The ligands were found active against α-chymotrypsin with IC50 ± S.E.M. = 305.0 ± 3.2 and 330.6 ± 1.6 μM respectively. The copper complexes of both the ligands were found active in inhibiting urease enzyme with IC50 ± S.E.M. = 10.7 ± 0.2 and 5.0 ± 0.1 μM respectively, as compared to standard inhibitor. Structure activity relationship (SAR) was evaluated using autodock programme. It was found that the active complexes block the entrance cavity to the enzyme. All the complexes were evaluated for their thermal degradation studies using TG-DTA analytical methods in static air. Thermodynamic and kinetic parameters were evaluated from the TG/DTA curves using Horowitz-Metzger method.
Synthesis and biological activity of some 3-aryl-3,4-dihydro-2h-benz[e]-1, 3-oxazines/6-bromo-3-aryl-3,4-dihydro-2h-benz[e]-1,3-oxazines
Shukla, Davender Kumar,Rani, Manju,Khan, Arif Ali,Tiwari, Kavita,Gupta, Rajinder K.
, p. 5921 - 5924 (2013/07/26)
N-(2-Hydroxy)-benzyl-arylamine (1) gives substantially pure 3-aryl-3,4-dihydro-2H-benz[e]-1,3-oxazines/6-bromo-3-aryl-3,4-dihydro-2H-benz[e] -1,3-oxazines (2) on cyclization with formaldehyde in methanol within 0.5-1.0 h at 65-68 C in excellent yields. Th
An efficient route for the synthesis of 3-(4-bromophenyl)-2-phenyl-3,4- dihydro-2 H-benzo[ e ][,32,]oxazaphosphinine, its P-chalcogenides and metal complexes
Shukla, Davender Kumar,Rani, Manju,Khan, Arif Ali
, p. 1088 - 1094 (2013/09/02)
2-[(4-bromophenylamino)-methyl]-phenol (1) gave substantially pure 3-(4-bromophenyl)-2-phenyl-3,4-dihydro-2H-benzo[e][1,3,2]- oxazaphosphinine (2) on cyclization with phenyldichlorophosphine in toluene at 0 °C. Reaction of 2 with H2O2 in dichloromethane gave selectively 3. P-chalcogenides (4 and 5) were prepared by reacting 2 with elemental S and Se powder in toluene, whereas the tungsten pentacarbonyl complex 6 was prepared by reacting 2 with [W(CO)5(CH3CN)] in tetrahydrofuran at 25°C. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures.
