17082-32-5Relevant academic research and scientific papers
Preparing magnetic multicomponent catalysts via a bio-inspired assembly for heterogeneous reactions
Song, Wentong,Tao, Shengyang,Yu, Yongxian,Du, Xuanlu,Wang, Shuo
, p. 69909 - 69918 (2016)
This article reports a facile synthetic approach for preparing magnetic porous catalysts, on which various inorganic compounds are alternately loaded using a pyrogallic acid (PG)-assisted layer-by-layer (LbL) coating. The PG forms an adhesion and reductive layer on the surface of hierarchically porous silica, and Pd, Al2O3, ZrO2, or FeOx can then be introduced on the surface of the material. Compared with the conventional impregnation method, the PG layer obviously improves the dispersion of catalysts and greatly reduces the blocking of the pores, which is caused by the formation of metal oxide catalysts. At the same time, the reduction properties of the layer help to reduce the diameter of the Pd nanoparticles to 5 ± 1.3 nm. The Fe3+ ions are partially reduced into Fe2+ by the PG layer to form Fe3O4, which endows the porous catalysts with a magnetic separation property. The synthesized multicomponent catalysts show excellent catalytic activity for various reactions, including the Suzuki Miyaura coupling, reduction, Knoevenagel condensation and Friedel-Crafts alkylation reactions. The TOF values show an improvement of 2 to 4 times over those of the catalysts prepared by the traditional impregnation method. The multicomponent magnetic catalysts also exhibit superior catalytic performance for many one-pot multistep cascade reactions.
Cascade Knoevenagel condensation-chemoselective transfer hydrogenation catalyzed by Pd nanoparticles stabilized on amine-functionalized aromatic porous polymer
Puthiaraj, Pillaiyar,Yu, Kwangsun,Baeck, Sung-Hyeon,Ahn, Wha-Seung
, p. 298 - 307 (2019/09/13)
An aromatic porous polymer incorporated with carbonyl functionality (APP) was prepared via a facile route of Friedel-Crafts reaction. Subsequent reaction with diethylenetriamine via Schiff-base chemistry produced the amine-functionalized porous polymer (D
Chemoselective Hydrazine-mediated Transfer Hydrogenation of Nitroarenes by Co3O4 Nanoparticles Immobilized on an Al/Si-mixed Oxide Support
Reddy, P. Linga,Tripathi, Mohit,Arundhathi,Rawat, Diwan S.
, p. 785 - 791 (2017/04/13)
Cobalt oxide nanoparticles (size 2 to 3.5 nm) were successfully impregnated on an alumina–silica (mixed oxide) support through an experimentally viable and easily reproducible protocol. The prepared material was well characterized by XRD, HR-TEM, BET surface area, EDX and XPS analyses. Porous alumina–silica having a high surface area served as a protective heterogeneous support on which the well-dispersed Co3O4 nanoparticles served as an active catalytic species for the hydrazine-mediated transfer hydrogenation of nitroarenes. About 2 mol % of the active catalyst in ethanol at 60 °C was adequate for a successful conversion. Moreover, transfer hydrogenation of nitroarenes by the catalyst was found to take place chemoselectively in the presence of other labile functional groups such as halide, alkene, nitrile, carbonyl, and ester. This inexpensive catalyst was also able to catalyze the reaction on a gram scale reaction and found to be robust and recyclable up to eight runs.
Core-shell palladium nanoparticle@metal-organic frameworks as multifunctional catalysts for cascade reactions
Zhao, Meiting,Deng, Ke,He, Liangcan,Liu, Yong,Li, Guodong,Zhao, Huijun,Tang, Zhiyong
supporting information, p. 1738 - 1741 (2014/03/21)
Uniform core-shell Pd@IRMOF-3 nanostructures, where single Pd nanoparticle core is surrounded by amino-functionalized IRMOF-3 shell, are prepared by a facile mixed solvothermal method. When used as multifunctional catalysts, the Pd@IRMOF-3 nanocomposites exhibit high activity, enhanced selectivity, and excellent stability in the cascade reaction. Both experimental evidence and theoretical calculations reveal that the high catalytic performance of Pd@IRMOF-3 nanocomposites originates from their unique core-shell structures.
A Simple and Clean Synthesis of Polysubstituted 2,6-Dicyanoanilines Catalyzed by KF/alumina
Jain, Shubha,Keshwal, Balwant S.,Rajguru, Deepika,Bhagwat, Vasant W.
, p. 712 - 715 (2013/03/29)
A simple and clean synthesis of polysubstituted 2,6-dicyanoanilines has been developed via the reaction of arylidenemalonodinitriles with 1-arylethylidenemalonodinitriles in ethanol catalyzed by KF/ alumina. Use of non-hazardous solid base as a catalyst,
Molecular rotors: synthesis and evaluation as viscosity sensors
Sutharsan, Jeyanthy,Lichlyter, Darcy,Wright, Nathan E.,Dakanali, Marianna,Haidekker, Mark A.,Theodorakis, Emmanuel A.
experimental part, p. 2582 - 2588 (2010/05/01)
It has been shown that compounds containing the p-N,N-dialkylaminobenzylidene cyanoacetate motif can serve as fluorescent non-mechanical viscosity sensors. These compounds, referred to as molecular rotors, belong to a class of fluorescent probes that are
A novel reductive cyclization of arylmethylidenemalononitrile promoted by low-valent titanium
Shi, Daqing,Zhao, Hong,Wang, Xiangshan,Yao, Changsheng,Zhou, Longhu
, p. 3311 - 3317 (2007/10/03)
The intermolecular and intramolecular reductive coupling reactions of arylmethylidenemalononitriles induced by low-valent titanium have been studied. A possible reaction mechanism is proposed.
Structure-activity relationship of new organic NLO materials based on push-pull azodyes. 1: Synthesis and molecular properties of the dyes
Tirelli,Altomare,Solaro,Ciardelli,Meier,Bosshard,Guenter
, p. 122 - 128 (2007/10/03)
Several new push-pull azobenzene dyes were synthesized by diazonium salt coupling of electron-poor anilines with N,N-dialkylanilines. Their dipole moments and first-order hyperpolarizabilities were evaluated respectively from the concentration dependence of the dielectric constant of solutions in apolar solvents and by the electric-field-induced-second-harmonic-generation (EFISH) technique. Investigation of the influence of both nature and steric hindrance of the electron-withdrawing group allowed to highlight a significant deviation from linearity in the relationship between dipole moments and first-order hyperpolarizabilities. This effect was particularly noticeable when multiple electron withdrawing groups pointing in different directions were present on the same phenyl ring. Johann Ambrosius Barth 1998.
