3159-01-1Relevant articles and documents
New chiral α-diimine nickel(II) complexes bearing ortho-sec-phenethyl groups for ethylene polymerization
Wang, Fuzhou,Yuan, Jianchao,Song, Fengying,Li, Jing,Jia, Zong,Yuan, Bingnian
, p. 319 - 327 (2013)
A series of new α-diimine nickel(II) catalysts bearing bulky chiral sec-phenethyl groups have been synthesized and characterized. The molecular structure of representative chiral ligand, bis[N,N′-(4-methyl-2,6-di-sec- phenethylphenyl)imino]-1,2-dimethylethane rac-1c and chiral complexes, {bis[N,N′-(4-methyl-2-sec-phenethylphenyl)imino]-2,3-butadiene} dibromidonickel rac-2a and bis{bis[N,N′-(4-methyl-2-sec-phenethylphenyl) imino]-2,3-butadiene}dibromidonickel rac-2b, were confirmed by X-ray crystallographic analysis. Complex rac-2c bearing two chiral sec-phenethyl groups in the ortho-aryl position and a methyl group in the para-aryl position, activated by diethylaluminum chloride (DEAC), showed highly catalytic activity for the polymerization of ethylene [4.12 × 106 g PE (mol Ni.h.bar)-1], and produced highly branched polyethylenes under low ethylene pressure (branching degree: 104, 118 and 126 branches/1000 C at 20, 40 and 60°C, respectively). Chiral 20-electron bis-α-diimine Ni(II) complex rac-2b also exhibited high activity toward ethylene polymerization [1.71 × 106 g PE (mol Ni · h · bar)-1]. The type and amount of branches of the polyethylenes obtained were determined by 1H and 13C NMR. Copyright
On the Superior Activity of In(I) versus In(III) Cations Toward ortho-C-Alkylation of Anilines and Intramolecular Hydroamination of Alkenes
Li, Zhilong,Yang, Shengwen,Thiery, Guillaume,Gandon, Vincent,Bour, Christophe
, p. 12947 - 12959 (2020/11/23)
An efficient ortho-C-alkylation of unprotected anilines with a variety of styrenes and alkenes using a univalent cationic indium(I) catalyst is reported. Mechanistic studies revealed that the reaction likely proceeds via a tandem hydroamination/Hofmann-Martius rearrangement. The high compatibility between the cationic indium(I) complex and primary anilines led us to develop an In(I)+-catalyzed hydroamination of alkenes using unprotected primary and secondary alkenylamines. Computations support the catalytic activity of naked In(I)+ ions, with an outer sphere mechanism for the C-N bond formation and a potentially inner sphere protodemetallation.
New nickel(II) diimine complexes bearing phenyl and sec-phenethyl groups: Synthesis, characterization and ethylene polymerization behaviour
Wang, Fuzhou,Yuan, Jianchao,Li, Qingshan,Tanaka, Ryo,Nakayama, Yuushou,Shiono, Takeshi
, p. 477 - 483 (2014/07/07)
A series of nickel(II) catalysts containing phenyl and chiral sec-phenethyl groups, {[(4-R1-2-R2C6H2-Rfnet C)2Nap]NiBr2} (Nap: 1,8-naphthdiyl, R1=Me, R2=Ph (3a); R1=Me, R2=sec-phenethyl (3b); R1=Cl, R2=sec-phenethyl (3c); R1=Me, R 2=Me (3d) were synthesized and characterized. All organic compounds were fully characterized by FT-IR and NMR spectroscopy and elemental analysis. The single crystal for X-ray crystallography was isolated from 3a in CH 2Cl2/n-hexane under air; the crystal structure showed a binuclear complex 3a, in which each nickel atom was six-coordinate. The two nickel atoms together with two bromine atoms form a planar four-membered ring, with a bromine and H2O axial ligands. These complexes, activated by diethylaluminum chloride and chiral nickel pre-catalysts rac-3c, exhibited good activities (up to 2.85×106g PE (mol Ni h bar)-1) for ethylene polymerization, and produced polyethylene products with a high degree of branching (up to 117 branched per 1000 carbons) at high temperature. The type and amount of branches of the polyethylenes obtained were determined by 1H and 13C NMR spectroscopy. Copyright
