25660-37-1Relevant articles and documents
Boger synthesis of 2-azolyl-substituted pyridines
Bunev,Statsyuk,Ostapenko,Purygin
, (2014)
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NHC-containing manganese(I) electrocatalysts for the two-electron reduction of CO2
Agarwal, Jay,Shaw, Travis W.,Stanton, Charles J.,Majetich, George F.,Bocarsly, Andrew B.,Schaefer, Henry F.
, p. 5152 - 5155 (2014)
The synthesis and characterization of the first catalytic manganese N-heterocyclic carbene complexes are reported: MnBr(N-methyl-N'-2- pyridylbenzimidazol-2-ylidine)(CO)3 and MnBr(N-methyl-N'-2- pyridylimidazol-2-ylidine)(CO)3. Both new species mediate the reduction of CO2 to CO following two-electron reduction of the MnI center, as observed with preparative scale electrolysis and verified with 13CO2. The two-electron reduction of these species occurs at a single potential, rather than in two sequential steps separated by hundreds of millivolts, as is the case for previously reported MnBr(2,2'-bipyridine)(CO)3. Catalytic current enhancement is observed at voltages similar to MnBr(2,2'-bipyridine)(CO)3. Catalytic manganese N-heterocyclic carbene complexes have been synthesized and characterized: [MnBrL(CO)3] (see scheme; L=N-methyl-N'-2- pyridylbenzimidazol-2-ylidine or N-methyl-N'-2-pyridylimidazol-2-ylidine). Both species mediate the reduction of CO2 to CO following two-electron reduction of the MnI center at a single potential, as observed with preparative scale electrolysis and verified with 13CO2.
Re(I) NHC Complexes for Electrocatalytic Conversion of CO2
Stanton, Charles J.,Machan, Charles W.,Vandezande, Jonathon E.,Jin, Tong,Majetich, George F.,Schaefer, Henry F.,Kubiak, Clifford P.,Li, Gonghu,Agarwal, Jay
, p. 3136 - 3144 (2016)
The modular construction of ligands around an N-heterocyclic carbene building block represents a flexible synthetic strategy for tuning the electronic properties of metal complexes. Herein, methylbenzimidazolium-pyridine and methylbenzimidazolium-pyrimidi
Monodentate Benzo[d]imidazole-Based Iridium(III) Complexes and Their Dual Fluorescent and Phosphorescent Emissions
Ryu, Chan Hee,Kim, Mingi,Sohn, Changho,Hong, Ju Hyun,Im, Sehee,Kim, So Yeon,Lee, Kang Mun
, p. 176 - 183 (2020)
We herein reported the preparation of three heteroleptic iridium complexes possessing the monodentate benzo[d]imidazole ligand, namely IrBzH (bis[2-(4,6-difluorophenyl)pyridinato-C^N](1-pyridin-2-yl)-1H-benzo[d]imidazolate)iridium(III)), IrBzCN (bis[2-(4,6-difluorophenyl)pyridinato-C^N](2-(1H-benzo[d]imidazolate-1-yl)isonicotinonitrile)iridium(III)), and IrBzBr (bis[2-(4,6-difluorophenyl)pyridinato-C′N](1-(4-bromopyridin-2-yl)-1H-benzo[d]imidazolate)iridium(III)). The successful preparation of these complexes was confirmed by multinuclear NMR spectroscopy and elemental analysis, while the molecular structures were determined by X-ray diffraction. The photoluminescence spectra of all three complexes in toluene at ambient temperature exhibited a dual-emissive pattern in the high- and low-energy regions. For IrBzCN and IrBzBr, the emissions were simultaneous in accordance with the excitation energies (λem = 342 and 370 nm), indicating that exhibiting both fluorescent (in the high-energy region) and phosphorescent (in the low-energy region) emissions is an inherent property of these complexes. Time-dependent density functional theory calculations verified that each fluorescent emission of the Ir complexes is associated with a ligand-to-ligand charge transfer transition, and the phosphorescent emission can be attributed to typical triplet metal-to-ligand charge transfer transitions between Ir3+ and the difluorophenylpyridine ligand.
Functionalization of superparamagnetic Fe3O4@SiO2 nanoparticles with a Cu(II) binuclear Schiff base complex as an efficient and reusable nanomagnetic catalyst for N-arylation of α-amino acids and nitrogen-containing heterocycles with aryl halides
Sardarian,Kazemnejadi,Esmaeilpour
, (2020/10/20)
Fe3O4@SiO2 nanoparticles was functionalized with a binuclear Schiff base Cu(II)-complex (Fe3O4@SiO2/Schiff base-Cu(II) NPs) and used as an effective magnetic hetereogeneous nanocatalyst for the N-arylation of α-amino acids and nitrogen-containig heterocycles. The catalyst, Fe3O4@SiO2/Schiff base-Cu(II) NPs, was characterized by Fourier transform infrared (FTIR) and ultraviolet-visible (UV-vis) analyses step by step. Size, morphology, and size distribution of the nanocatalyst were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and dynamic light scatterings (DLS) analyses, respectively. The structure of Fe3O4 nanoparticles was checked by X-ray diffraction (XRD) technique. Furthermore, the magnetic properties of the nanocatalyst were investigated by vibrating sample magnetometer (VSM) analysis. Loading content as well as leaching amounts of copper supported by the catalyst was measured by inductive coupled plasma (ICP) analysis. Also, thermal studies of the nanocatalyst was studied by thermal gravimetric analysis (TGA) instrument. X-ray photoelectron spectroscopy (XPS) analysis of the catalyst revealed that the copper sites are in +2 oxidation state. The Fe3O4@SiO2/Schiff base-Cu(II) complex was found to be an effective catalyst for C–N cross-coupling reactions, which high to excellent yields were achieved for α-amino acids as well as N-hetereocyclic compounds. Easy recoverability of the catalyst by an external magnet, reusability up to eight runs without significant loss of activity, and its well stability during the reaction are among the other highlights of this catalyst.
N -Arylation of (hetero)arylamines using aryl sulfamates and carbamates via C-O bond activation enabled by a reusable and durable nickel(0) catalyst
Dindarloo Inaloo, Iman,Majnooni, Sahar,Eslahi, Hassan,Esmaeilpour, Mohsen
, p. 13266 - 13278 (2020/10/07)
An effective and general aryl amination protocol has been developed using a magnetically recoverable Ni(0) based nanocatalyst. This new stable catalyst was prepared on Fe3O4@SiO2 modified by EDTA and investigated by FT-IR, EDX, TEM, XRD, DLS, FE-SEM, XPS, NMR, TGA, VSM, ICP and elemental analysis techniques. The reaction proceeded via carbon-oxygen bond cleavage of (hetero)aryl carbamates and sulfamates under simple and mild conditions without the use of any external ligands. This method demonstrated functional group tolerance in the N-arylation of various nitrogen-containing compounds as well as aliphatic amines, anilines, pyrroles, pyrazoles, imidazoles, indoles, and indazoles with good to excellent yields. Furthermore, the catalyst could be easily recovered by using an external magnetic field and directly reused at least six times without notable reduction in its activity. This journal is
