5393-49-7Relevant articles and documents
α-Diimine synthesis via titanium-mediated multicomponent diimination of alkynes with C-nitrosos
Cheng, Yukun,Egger, Dominic T.,Frye, Connor W.,Kounalis, Errikos,Pearce, Adam J.,Tonks, Ian A.
, p. 1469 - 1477 (2022/02/11)
α-Diimines are commonly used as supporting ligands for a variety of transition metal-catalyzed processes, most notably in α-olefin polymerization. They are also precursors to valuable synthetic targets, such as chiral 1,2-diamines. Their synthesis is usually performed through acid-catalyzed condensation of amines with α-diketones. Despite the simplicity of this approach, accessing unsymmetrical α-diimines is challenging. Herein, we report the Ti-mediated intermolecular diimination of alkynes to afford a variety of symmetrical and unsymmetrical α-diimines through the reaction of diazatitanacyclohexadiene intermediates with C-nitrosos. These diazatitanacycles can be readily accessed in situ via the multicomponent coupling of TiNR imidos with alkynes and nitriles. The formation of α-diimines is achieved through formal [4 + 2]-cycloaddition of the C-nitroso to the Ti and γ-carbon of the diazatitanacyclohexadiene followed by two subsequent cycloreversion steps to eliminate nitrile and afford the α-diimine and a Ti oxo.
Ruthenium-Catalyzed Dehydrogenation Through an Intermolecular Hydrogen Atom Transfer Mechanism
Huang, Lin,Bismuto, Alessandro,Rath, Simon A.,Trapp, Nils,Morandi, Bill
supporting information, p. 7290 - 7296 (2021/03/01)
The direct dehydrogenation of alkanes is among the most efficient ways to access valuable alkene products. Although several catalysts have been designed to promote this transformation, they have unfortunately found limited applications in fine chemical synthesis. Here, we report a conceptually novel strategy for the catalytic, intermolecular dehydrogenation of alkanes using a ruthenium catalyst. The combination of a redox-active ligand and a sterically hindered aryl radical intermediate has unleashed this novel strategy. Importantly, mechanistic investigations have been performed to provide a conceptual framework for the further development of this new catalytic dehydrogenation system.
BIS-IMINE TITANIUM COMPLEX, CATALYTIC SYSTEM COMPRISING SAID BIS-IMINE TITANIUM COMPLEX AND PROCESS FOR THE (CO)POLYMERIZATION OF CONJUGATED DIENES
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Page/Page column 33; 34, (2019/04/26)
Bis-imine titanium complex having general formula (I): wherein: R1 and R2, mutually identical or different, represent a hydrogen atom; or are selected from linear or branched, optionally halogenated, C1-C20 alky
α-Diamine Nickel Catalysts with Nonplanar Chelate Rings for Ethylene Polymerization
Liao, Heng,Zhong, Liu,Xiao, Zefan,Zheng, Ting,Gao, Haiyang,Wu, Qing
, p. 14048 - 14055 (2016/09/21)
A series of novel α-diamine nickel complexes, (ArNH-C(Me)-(Me)C-NHAr)NiBr2, 1: Ar=2,6-diisopropylphenyl, 2: Ar=2,6-dimethylphenyl, 3: Ar=phenyl), have been synthesized and characterized. X-ray crystallographic analysis showed that the coordination geometry of the α-diamine nickel complexes is markedly different from conventional α-diimine nickel complexes, and that the chelate ring (N-C-C-N-Ni) of the α-diamine nickel complex is significantly distorted. The α-diamine nickel catalysts also display different steric effects on ethylene polymerization in comparison to the α-diimine nickel catalyst. Increasing the steric hindrance of the α-diamine ligand by substitution of the o-methyl groups with o-isopropyl groups leads to decreased polymerization activity and molecular weight; however, catalyst thermal stability is significantly enhanced. Living polymerizations of ethylene can be successfully achieved using 1/Et2AlCl at 35 °C or 2/Et2AlCl at 0 °C. The bulky α-diamine nickel catalyst 1 with isopropyl substituents can additionally be used to control the branching topology of the obtained polyethylene at the same level of branching density by tuning the reaction temperature and ethylene pressure.
METHOD OF PRODUCING ORGANIC SILICON COMPOUND
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Paragraph 0032, (2017/03/23)
PROBLEM TO BE SOLVED: To provide a method of producing an organic silicon compound efficiently by improving a catalyst for hydrosilylation reactions of alkenes and alkynes. SOLUTION: An organic silicon compound can be produced efficiently by using an iron
Potassium Tellurocyanate Mediated Coupling Reactions of N-(1-Chloroethylidene)Arylamines
Al-Jadaan, Shaker A.,Al-Masoudi, Wasfi A.,Saeed, Bahjat A.,Al-Rubaie, Ali Z.
, p. 1823 - 1830 (2015/11/02)
The reaction of potassium tellurocyanate (prepared in situ) with N-(1-chloroethylidene)arylamines (i.e., 4-RC6H4N = C(CH3)Cl, where R = H, Cl, CH3 and NO2) in DMSO solution gave unexpectedly, after hy
Highly active and cis-1,4 selective polymerization of 1,3-butadiene catalyzed by cobalt(II) complexes bearing α-diimine ligands
Jia, Xiangyu,Liu, Heng,Hu, Yanming,Dai, Quanquan,Bi, Jifu,Bai, Chenxi,Zhang, Xuequan
, p. 1560 - 1569 (2013/10/01)
A series of cobalt(II) complexes bearing α-diimine ligands were synthesized and characterized by elemental and spectroscopic analysis. These complexes had the general formulas [ArN=C(Me)-(Me)C=NAr]CoCl2 (Ar = C6H5, 3a; 4-M
A thermally robust amine-imine nickel catalyst precursor for living polymerization of ethylene above room temperature
Gao, Haiyang,Hu, Haibin,Zhu, Fangming,Wu, Qing
supporting information; experimental part, p. 3312 - 3314 (2012/04/23)
A bulky amine-imine nickel complex containing two 2,6-diisopropyl substituents after activation with MMAO or Et2AlCl can polymerize ethylene in a living fashion over a period of 120 minutes at room temperature or above. The Royal Society of Chemistry 2012.
In vitro bacteriostatic and DNA interaction studies of drug-based mixed-ligand complexes of cobalt(II)
Patel, Mohan,Chhasatia, Mehul,Bhatt, Bhupesh
experimental part, p. 220 - 230 (2012/03/10)
The dinuclear cobalt(II) complexes with ciprofloxacin and bidentate ligands were synthesized and characterized using infrared spectra, electronic spectra, magnetic measurements, elemental analyses, thermal investigation, and mass spectroscopy. Here in we
Antibacterial and DNA interaction studies of zinc(II) complexes with quinolone family member, ciprofloxacin
Patel, Mohan,Chhasatia, Mehul,Parmar, Pradhuman
experimental part, p. 439 - 446 (2010/04/02)
DNA binding and cleavage characteristics of Zn(II) complexes have been investigated. The DNA interaction property of the complexes has been investigated using absorption spectra, viscosity measurements, as well as gel electrophoresis studies. Intrinsic bi
