75350-14-0Relevant academic research and scientific papers
Exceptionally high lactide polymerization activity of zirconium complexes with bridged diketiminate ligands
El-Zoghbi, Ibrahim,Whitehorne, Todd J. J.,Schaper, Frank
, p. 9376 - 9387 (2013)
A cyclohexanediyl-bridged, bis(N-xylyl) diketiminate ligand, (±)-C6H10(nacnacXylH)2, LH2 (Xyl = 2,6-dimethylphenyl), was obtained from the reaction of [(2,6-dimethylphenyl)amino]-pent-3-en-2-one first
β-Enaminone Synthesis from 1,3-Dicarbonyl Compounds and Aliphatic and Aromatic Amines Catalyzed by Iron Complexes of Fused Bicyclic Imidazo[1,5-a]pyridine Derived N-Heterocyclic Carbenes
Prakasham,Gangwar, Manoj Kumar,Ghosh, Prasenjit
, p. 295 - 313 (2019/01/24)
A series of Fe–NHC complexes (1–2)c of the fused bicyclic imidazo[1,5-a]pyridine framework of the type [CpFe(2-R-imidazo[1,5-a]pyridin-3-ylidene)(CO)2]BF4 {R = mesityl (1c), nPr (2c)} successfully carried out the synthesis of β-enamino ketones (3–10) and (17–27) and β-enamino esters (11–16) and (28–36) by the condensation of acyclic and cyclic 1,3-dicarbonyl compounds and various aliphatic and aromatic amines in the presence of light irradiation. Quite significantly, the catalytically relevant substrate adduct species of the type [CpFe(NHC)(acac)] (2e) and the product adduct species of the type [CpFe(NHC)(β-enaminone)] (2f) of the Fe–NHC precatalyst (2c) have been detected by mass spectrometry study. The [CpFe(2-R-imidazo[1,5-a]pyridin-3-ylidene)(CO)2]BF4 {R = mesityl (1c), nPr (2c)} complexes were obtained from their respective N–heterocyclic carbene precursors namely, the 2-R-imidazo[1,5-a]pyridin-2-ium chloride {R = mesityl (1a), nPr (2a)} by the reaction with CpFe(CO)2I in the presence of KN(SiMe3)2 followed by the salt metathesis reaction with AgBF4.
Bimetallic Ag-Cu alloy nanoparticles as a highly active catalyst for the enamination of 1,3-dicarbonyl compounds
Rout, Lipeeka,Kumar, Aniket,Dhaka, Rajendra S.,Dash, Priyabrat
, p. 49923 - 49940 (2016/06/15)
Bimetallic nanoparticles, particularly those based on copper, have recently attracted a great deal of attention for the development of low cost and highly active catalysts due to the synergistic interaction between individual metal components. In this work, bimetallic Ag-Cu alloy nanoparticles were explored as a highly active and reusable catalyst for the enamination of 1,3-dicarbonyls using diverse amines. The nanocatalysts were intensively characterized by ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), high-resolution transmission electron microscopy-energy-dispersive spectroscopy (HRTEM-EDS) and valence band and core level X-ray photoelectron spectroscopy (XPS) to study the effect of the bimetallic structure and composition. In comparison to monometallic Ag and Cu nanoparticles, the alloyed Ag-Cu nanoparticles showed a high catalytic performance and the resultant catalytic activity was dependant on the Ag to Cu ratio. This enhanced catalytic activity should be related to the electronic interaction between Ag and Cu nanoparticles formed due to the intimate contact between them. Our study may serve as a foundation for designing efficient alloyed nanocatalysts for fine chemical synthesis via enamination reactions.
Aluminum methyl and isopropoxide complexes with ketiminate ligands: Synthesis, structural characterization and ring-opening polymerization of cyclic esters
Altaf, Cigdem Tuc,Wang, Haobing,Keram, Maryam,Yang, Yang,Ma, Haiyan
, p. 11 - 20 (2014/07/07)
Mono(ketiminate) aluminum dimethyl complexes 1a-5a and bis(ketiminate) aluminum methyl complex 2b were synthesized via the reactions of AlMe 3 with various N-aryl substituted ketimine compounds in a 1:1 or 1:2 molar ratio, respectively. The rea
Zirconium and hafnium complexes supported by linked bis(β- diketiminate) ligands: Synthesis, characterization and catalytic application in ethylene polymerization
Gong, Shaogang,Ma, Haiyan,Huang, Jiling
scheme or table, p. 8237 - 8247 (2010/03/04)
Zirconium and hafnium complexes bearing new 1,2-ethanediyl- or 1,3-propanediyl-linked bis(β-diketiminate) ligands, [{CnH 2n-(BDIAr)2}MCl2] (Ar = 2,6-Me 2-C6H3, 2,6-Cl2-C6H 3, 2,6-iPr2-C6H3; M = Zr, n = 2 (4a-c), n = 3 (5a-c); M = Hf, n = 2 (6b)), were synthesized via the reaction of MCl4·2THF and one equivalent of dilithium salt of the corresponding ligand. Distorted trigonal prismatic and octahedral coordination geometries as well as C1-symmetric structures are found for zirconium complexes 4c and 5c in the solid state. Variable temperature 1H NMR spectra indicated the fluxional nature of 4a and 5a in solution. Upon activation with methylaluminoxane (MAO), all these complexes except hafnium complex 6b displayed moderate catalytic activities for ethylene polymerization. 1,2-Ethanediyl-linked complexes 4a and 4b are generally more active than their 1,3-propanediyl-linked analogues. The substituents at the ortho-positions of the phenyl rings have different effect on the catalytic activities of 1,2-ethanediyl-linked series or 1,3-propanediyl-linked series. It is noteworthy that even at a low Al/Zr molar ratio of 500, the catalytic activities of these zirconium complexes could be retained. Polyethylenes with broad molecular weight distributions (MWD = 15.3-20.3) were produced, which might result from the fluxional character of the zirconium complexes. The linear structure of obtained polyethylenes was further determined by 13C NMR spectroscopy and DSC analysis. The Royal Society of Chemistry 2009.
Imidoylketene Imines, III. Preparation and Conformation of Vinylogous Ureas
Goerdeler, Joachim,Lindner, Christian
, p. 2499 - 2508 (2007/10/02)
A number of new β-aminocroton- and cinnamamides (3), often with 2-cyano, -keto, or -ester groups, were prepared by addition of the corresponding secondary enamines 1 to isocyanates.In the case of tert-butyl isocyanate the use of zinc chloride was helpful.
