1866-39-3Relevant articles and documents
Preparation of high-magnetization Fe3O4-NH 2-Pd (0) catalyst for heck reaction
Ma, Mingliang,Zhang, Qiuyu,Yin, Dezhong,Dou, Jinbo,Zhang, Hepeng,Xu, Hailong
, p. 168 - 172 (2012)
A magnetically separable Fe3O4-NH2-Pd (0) catalyst was easily synthesized by immobilizing Pd nanoparticles on the surface of magnetic Fe3O4-NH2 microspheres. It was found that the combination of Fe3O4 and triethylene tetramine (TETA) could give rise to structurally stable catalytic sites. Furthermore, the high-magnetization Fe3O4-NH 2-Pd(0) catalyst can be recovered by magnet and reused for six runs for Heck reaction without significant loss in catalytic activity.
Synthesis, characterization, luminescence, antibacterial, and catalytic activities of a palladium(II) complex involving a Schiff base
Ma, De-Yun,Zhang, Le-Xin,Rao, Xuan-Ye,Wu, Tong-Liang,Li, Dong-Hao,Xie, Xiao-Qun
, p. 1486 - 1496 (2013)
A new Pd(II) complex of fluorine-containing Schiff base ligand, [Pd 2(L)2Cl2] (1) [L = N-(4-fluorobenzylidene)-2,6- diethylbenzenamine], has been synthesized using solvothermal method and characterized by elemental analysis, IR-spectroscopy, thermogravimetric analysis, powder X-ray diffraction, UV-vis absorption spectra, and single-crystal X-ray diffraction Complex 1 is a μ-chloro-bridged dinuclear cyclometallated Pd(II) complex Thermal analysis indicates that 1 is quite stable to heat 1 exhibits quadruple emissions in the solid state (λ max = 766 nm) and possesses fluorescence lifetimes (τ1 = 87.20 ns, τ2 = 190.45 ns, and τ3 = 1805.10 ns at 616 nm); broad structureless bands at 690-800 nm are tentatively assigned to an excimeric 3IL transition The Schiff base (L) and its palladium(II) compound (1) have been screened for their antibacterial activity against several bacteria, and the results are compared with the activity of penicillin Moreover, 1 has been shown to be highly effective in the Heck reaction of 4-bromotoluene with acrylic acid
Photocatalytic Oxidative [2+2] Cycloelimination Reactions with Flavinium Salts: Mechanistic Study and Influence of the Catalyst Structure
Hartman, Tomá?,Reisnerová, Martina,Chudoba, Josef,Svobodová, Eva,Archipowa, Nataliya,Kutta, Roger Jan,Cibulka, Radek
, p. 373 - 386 (2021/02/01)
Flavinium salts are frequently used in organocatalysis but their application in photoredox catalysis has not been systematically investigated to date. We synthesized a series of 5-ethyl-1,3-dimethylalloxazinium salts with different substituents in the positions 7 and 8 and investigated their application in light-dependent oxidative cycloelimination of cyclobutanes. Detailed mechanistic investigations with a coumarin dimer as a model substrate reveal that the reaction preferentially occurs via the triplet-born radical pair after electron transfer from the substrate to the triplet state of an alloxazinium salt. The very photostable 7,8-dimethoxy derivative is a superior catalyst with a sufficiently high oxidation power (E=2.26 V) allowing the conversion of various cyclobutanes (with Eox up to 2.05 V) in high yields. Even compounds such as all-trans dimethyl 3,4-bis(4-methoxyphenyl)cyclobutane-1,2-dicarboxylate can be converted, whose opening requires a high activation energy due to a missing pre-activation caused by bulky adjacent substituents in cis-position.
Amino Group Functionalized Hf-Based Metal-Organic Framework for Knoevenagel-Doebner Condensation
Das, Aniruddha,Anbu, Nagaraj,Gogoi, Chiranjib,Dhakshinamoorthy, Amarajothi,Biswas, Shyam
, p. 3396 - 3403 (2021/08/20)
A Hf(IV) metal-organic framework (MOF) with di-amino functionalized linker was obtained as a crystalline solid with UiO-67 topology under solvothermal reaction conditions. The guest free form of Hf(IV) MOF (1′) was efficiently employed as a heterogeneous catalyst to synthesize cinnamic acid derivatives via Knoevenagel-Doebner reaction for the first time. The catalyst (1′) was efficiently active to directly achieve cinnamic acid from benzaldehyde and malonic acid. The solid retained its activity up to 6th cycle with no decay in its activity. The noticeable advantages of the catalyst are its milder reaction conditions, high yield, high stability, recyclable nature towards catalysis and wide substrate scope as well as shape-selective behaviour. The possible mechanism of the reaction was also studied thoroughly with suitable control experiments.
