27852-91-1Relevant articles and documents
Copper complexes of 1,4-diazabutadiene ligands: Tuning of metal oxidation state and, application in catalytic C-C and C-N bond formation
Mukherjee, Aparajita,Basu, Semanti,Bhattacharya, Samaresh
, (2019/11/11)
Reaction of 1,4-diazabutadiene (p-RC6H4N = C(H)(H)C = NC6H4R-p; R = OCH3, CH3, H and Cl; abbreviated as L-R) with CuCl2·2H2O in methanol at ambient temperature (25 °C) affords a group of doubly chloro-bridged dicopper complexes of type [{CuI(L-R)Cl}2], designated as 1-R. Similar reaction carried out in acetonitrile furnishes a family of doubly chloro-bridged dicopper complexes of type [{CuII(L-R)Cl2}2], designated as 2-R. Molecular structures of 1-OCH3 and 2-OCH3 have been determined by X-ray crystallography. While copper(I) is having a nearly tetrahedral N2Cl2 coordination sphere in 1-OCH3, the N2Cl3 coordination sphere around copper(II) is distorted square pyramidal in nature in 2-OCH3. Isolated 2-R complexes, on dissolution in methanol, are found to undergo facile reduction of the metal center to generate the corresponding 1-R complexes. The 1-R and 2-R complexes show intense absorptions in the visible and ultraviolet regions. Cyclic voltammetry on the 1-R and 2-R complexes shows both metal-centered and ligand centered redox responses. The 1-R complexes are found to efficiently catalyze C-N cross-coupling reactions between arylboronic acids and aryl amines; while the 2-R complexes display notable catalytic efficiency for nitroaldol reactions.
Synthesis, Characterization and Catalytic Activity of Magnetic KI@Fe3O4 Nanoparticles for Henry Reaction Under Solvent Free Conditions
Rokhum, Lalthazuala,Pathak, Gunindra
, p. 2887 - 2898 (2019/05/28)
Abstract: In this paper, we, for the first time reported the synthesis of KI loaded Fe3O4 nanoparticles (KI@Fe3O4 NPs) and investigated its applications in the synthesis of β-nitroalcohol via Henry reaction at room temperature under solvent-free conditions. The synthesized KI@Fe3O4 nanoparticle was characterized by SEM, HRTEM, XRD, XPS, EDX, VSM and FT-IR spectroscopy techniques. The XRD peaks at 2θ = 21.9, 25.65, 33.54, 36.35, 40.97, 42.81, 44.79, 54.43, 57.37, 58.83 and 63.13° corresponds to the formation of crystalline KI@Fe3O4 NPs. The activity of the catalyst by varying the amount of KI loading on Fe3O4 NPs was also investigated. Mild reaction conditions, good yield, short reaction time, solvent-free conditions, easy recoverability and recyclability of the nanocatalysts are the major advantages of our method. Graphical Abstract: [Figure not available: see fulltext.].
Microwave-assisted synthesis of urea-containing zirconium metal-organic frameworks for heterogeneous catalysis of Henry reactions
Zhang, He,Gao, Xue-Wang,Wang, Li,Zhao, Xinsheng,Li, Qiu-Yan,Wang, Xiao-Jun
, p. 1358 - 1362 (2019/03/04)
Here we report the facile preparation of a urea-containing UiO-68 isoreticular zirconium metal-organic framework (MOF) with mixed dicarboxylate struts by utilizing a microwave-assisted heating method. It can work as an efficient hydrogen-bond-donating heterogeneous catalyst for Henry reactions of benzaldehydes and nitroalkanes. This mixed strut MOF exhibits improved catalytic activity compared to the pure urea-functionalized linker based analogue.