0000000001306063
AUTHOR
Yanping Ma
Enhancing performance of α‐diiminonickel precatalyst for ethylene polymerization by substitution with the 2,4‐bis(4,4'‐dimethoxybenzhydryl)‐6‐methylphenyl group
High activities in ethylene polymerization predetermine α‐diiminonickel precatalysts for potential industrial applications. In our study, we have synthesized and characterized a series of unsymmetrical 1‐(2,4‐bis(4,4′‐dimethoxybenzhydryl)‐6‐MeC6H2N)‐2‐arylimino‐acenaphthylene nickel(II) halides. The single‐crystal X‐ray diffraction study of representative compounds reveals distorted tetrahedral geometry. On activation with either Me2AlCl or modified methylaluminoxane, these nickel complexes exhibit high activities of the order of 106 g of PE (mol of Ni)−1 h−1 and produce polyethylene of generic application characterized by high molecular weight, narrow molecular weight distribution, and mod…
The chloro‐substituent enhances performance of 2,4‐bis (imino)pyridylchromium catalysts yielding highly linear polyethylene
The five unsymmetrical 2‐[1‐(2,4‐dibenzhydryl‐6‐chlorophenylimino)ethyl]‐6‐[1‐(arylimino)ethyl]pyridine compounds (aryl: 2,6‐Me2Ph L1 , 2,6‐Et2Ph L2 , 2,6‐i Pr2Ph L3 , 2,4,6‐Me3Ph L4 and 2,6‐Et2–4‐MePh L5 ) were prepared and characterized with FT‐IR and 1H/13C NMR spectroscopy as well as elemental analysis. The treatment of L1 – L5 with CrCl3·3THF affords the corresponding chromium chloride complexes (Cr1 – Cr5 ) in excellent yields. The molecular structures of Cr2 and Cr3 characterized by X‐ray diffraction show a distorted octahedral geometry with three nitrogen atoms and three chlorine atoms around the metal center. On activation with either MAO or MMAO, Cr1 – Cr5 collectively display hig…
2-(N,N-Diethylaminomethyl)-6,7-trihydroquinolinyl-8-ylideneamine-Ni(ii) chlorides: application in ethylene dimerization and trimerization
A series of Ni(II) complexes with the general formula [2-((NEt2)Me)-8-{N(Ar)}C9H8N]NiCl2, where Ar = 2,6-Me2C6H3 in Ni1, 2,6-Et2C6H3 in Ni2, 2,6-i-Pr2C6H3 in Ni3, 2,4,6-Me3C6H2 in Ni4, 2,6-Et2-4-MeC6H2 in Ni5, and 2,4,6-t-Bu3C6H2 in Ni6, has been prepared using a one-pot reaction of 2-(N,N-diethylaminomethyl)-6,7-dihydroquinolin-8(5H)-one with the corresponding aniline and nickel dichloride hexahydrate. The resultant complexes were characterized using elemental analysis and FT-IR spectroscopy, while the mononuclear Ni1 and Ni3 were also the subject of single-crystal X-ray diffraction study. On activation with MMAO, the complexes Ni1–Ni6 displayed good activity in ethylene oligomerization, f…
Ethylene oligomerization with 2-hydroxymethyl-5,6,7-trihydroquinolinyl-8-ylideneamine-Ni(II) chlorides
Abstract A series of Ni complexes of the general formula [2-(MeOH)-8-{N(Ar)}C9H8N]NiCl2, where Ar = 2,6-Me2C6H3 in Ni1; 2,6-Et2C6H3 in Ni2; 2,6-i-Pr2C6H3 in Ni3; 2,4,6-Me3C6H2 in Ni4; 2,6-Et2-4-MeC6H2 in Ni5 and 2,4,6-t-Bu3C6H2 in Ni6 has been synthesized and characterized by elemental analysis and IR spectroscopy. On activation with MMAO or Et2AlCl, these complexes showed high activity in ethylene oligomerization, reaching 2.23 × 106 g·mol–1 (Ni) h–1 at 30 °C with the Al/Ni ratio of 5500 and 9.11 × 105 g·mol–1 (Ni) h–1 with the Al/Ni of 800, respectively. Moreover, the content of α-C4 indicated high selectivity exceeding 99% in the Ni/Et2AlCl system. Comparing with the previous report by o…
Activity and Thermal Stability of Cobalt(II)-Based Olefin Polymerization Catalysts Adorned with Sterically Hindered Dibenzocycloheptyl Groups.
Five examples of unsymmetrical 2-(2,4-bis(dibenzocycloheptyl)-6-methylphenyl- imino)ethyl)-6-(1-(arylyimino)ethyl)pyridine derivatives (aryl = 2,6-Me2C6H3 in L1
Enhancing Performance of a Bis(arylimino)pyridine‐Iron Precatalyst for Ethylene Polymerization by Substitution with a 2,4‐Bis(4,4′‐dimethoxybenzhydryl)‐6‐methylphenyl Group
A series of unsymmetrical 2-(2,4-bis(bis(4-methoxyphenyl)methyl)-6-MeC6H2N)-6-(1-(arylimino)ethyl)pyridine-iron halides has been synthesized and characterized. The molecular structure of two representative species was determined by the single-crystal X-ray diffraction. Activated with either MAO or MMAO, the precatalysts displayed high activity, reaching 2.19×107 g PE (mol Fe)−1 h−1 at 60 °C in ethylene polymerization. The microstructural analysis of the polymers obtained indicates highly linear polyethylene containing a vinyl chain end.
Nickel(II) complexes with sterically hindered 5,6,7-trihydroquinoline derivatives selectively dimerizing ethylene to 1-butene
A series of nickel complexes bearing N,N-bidentate ligands has been synthesized and characterized by elemental analysis and infrared (IR) spectroscopy. High ethylene dimerization activity, reaching 2.43 × 106 g mol−1(Ni)h−1, was achieved by using these complexes as precatalysts activated with Me2AlCl. Moreover, the selectivity to obtain α-C4 was high (93%–96%). Comparing with the previous report by our group, the higher activity and selectivity may be attributed to the substituent at the 2-position within the ligand, creating the steric hindrance around the metal atom.
CCDC 2124204: Experimental Crystal Structure Determination
Related Article: Wenhua Lin, Ming Liu, Lei Xu, Yanping Ma, Liping Zhang, Zygmunt Flisak, Xinquan Hu, Tongling Liang, Wen‐Hua Sun|2022|Appl.Organomet.Chem.|36|e6596|doi:10.1002/aoc.6596
CCDC 1979970: Experimental Crystal Structure Determination
Related Article: Shi‐Fang Yuan, Zhe Fan, Qiuyue Zhang, Zygmunt Flisak, Yanping Ma, Yang Sun, Wen‐Hua Sun|2020|Appl.Organomet.Chem.|34 |e5638|doi:10.1002/aoc.5638
CCDC 2063053: Experimental Crystal Structure Determination
Related Article: Shi‐Fang Yuan, Zhe Fan, Mingyang Han, Yi Yan, Zygmunt Flisak, Yanping Ma, Tongling Liang, Wen‐Hua Sun|2021|Eur.J.Inorg.Chem.|2021|1571|doi:10.1002/ejic.202100145
CCDC 2005997: Experimental Crystal Structure Determination
Related Article: Jiaxin Li, Yanping Ma, Xinquan Hu, Zygmunt Flisak, Liang Tongling, Wen-Hua Sun|2020|New J.Chem.|44|17047|doi:10.1039/D0NJ04003G
CCDC 1979969: Experimental Crystal Structure Determination
Related Article: Shi‐Fang Yuan, Zhe Fan, Qiuyue Zhang, Zygmunt Flisak, Yanping Ma, Yang Sun, Wen‐Hua Sun|2020|Appl.Organomet.Chem.|34 |e5638|doi:10.1002/aoc.5638
CCDC 2063054: Experimental Crystal Structure Determination
Related Article: Shi‐Fang Yuan, Zhe Fan, Mingyang Han, Yi Yan, Zygmunt Flisak, Yanping Ma, Tongling Liang, Wen‐Hua Sun|2021|Eur.J.Inorg.Chem.|2021|1571|doi:10.1002/ejic.202100145
CCDC 2124203: Experimental Crystal Structure Determination
Related Article: Wenhua Lin, Ming Liu, Lei Xu, Yanping Ma, Liping Zhang, Zygmunt Flisak, Xinquan Hu, Tongling Liang, Wen‐Hua Sun|2022|Appl.Organomet.Chem.|36|e6596|doi:10.1002/aoc.6596
CCDC 1905876: Experimental Crystal Structure Determination
Related Article: Muhammad Zada, Liwei Guo, Yanping Ma, Wenjuan Zhang, Zygmunt Flisak, Yang Sun, Wen-Hua Sun|2019|Molecules|24|2007|doi:10.3390/molecules24102007
CCDC 1951481: Experimental Crystal Structure Determination
Related Article: Badral Gansukh, Qiuyue Zhang, Zygmunt Flisak, Tongling Liang, Yanping Ma, Wen‐Hua Sun|2020|Appl.Organomet.Chem.|34|e5471|doi:10.1002/aoc.5471
CCDC 1951482: Experimental Crystal Structure Determination
Related Article: Badral Gansukh, Qiuyue Zhang, Zygmunt Flisak, Tongling Liang, Yanping Ma, Wen‐Hua Sun|2020|Appl.Organomet.Chem.|34|e5471|doi:10.1002/aoc.5471
CCDC 1905877: Experimental Crystal Structure Determination
Related Article: Muhammad Zada, Liwei Guo, Yanping Ma, Wenjuan Zhang, Zygmunt Flisak, Yang Sun, Wen-Hua Sun|2019|Molecules|24|2007|doi:10.3390/molecules24102007
CCDC 2005998: Experimental Crystal Structure Determination
Related Article: Jiaxin Li, Yanping Ma, Xinquan Hu, Zygmunt Flisak, Liang Tongling, Wen-Hua Sun|2020|New J.Chem.|44|17047|doi:10.1039/D0NJ04003G