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Thermally Stable and Highly Efficient N,N,N-Cobalt Olefin Polymerization Catalysts Affixed with N-2,4-Bis(Dibenzosuberyl)-6-Fluorophenyl Groups. Catalysts 2022. [DOI: 10.3390/catal12121569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The cobalt(II) chloride N,N,N-pincer complexes, [2-{(2,4-(C15H13)2-6-FC6H2)N=CMe}-6-(ArN=CMe)C5H3N]CoCl2 (Ar = 2,6-Me2C6H3) (Co1), 2,6-Et2C6H3 (Co2), 2,6-i-Pr2C6H3 (Co3), 2,4,6-Me3C6H2 (Co4), 2,6-Et2-4-MeC6H2 (Co5), and [2,6-{(2,4-(C15H13)2-6-FC6H2)N=CMe}2C5H3N]CoCl2 (Co6), each containing at least one N-2,4-bis(dibenzosuberyl)-6-fluorophenyl group, were synthesized in good yield from their corresponding unsymmetrical (L1–L5) and symmetrical bis(imino)pyridines (L6). The molecular structures of Co1 and Co2 spotlighted their distorted square pyramidal geometries (τ5 value range: 0.23–0.29) and variations in steric hindrance offered by the dissimilar N-aryl groups. On activation with either MAO or MMAO, Co1–Co6 all displayed high activities for ethylene polymerization, with levels falling in the order: Co1 > Co4 > Co5 > Co2 > Co3 > Co6. Indeed, the least sterically hindered 2,6-dimethyl Co1 in combination with MAO exhibited a very high activity of 1.15 × 107 g PE mol−1 (Co) h−1 at the operating temperature of 70 °C, which dropped by only 15% at 80 °C and 43% at 90 °C. Vinyl-terminated polyethylenes of high linearity and narrow dispersity were generated by all catalysts, with the most sterically hindered, Co3 and Co6, producing the highest molecular weight polymers [Mw range: 30.26–33.90 kg mol−1 (Co3) and 42.90–43.92 kg mol−1 (Co6)]. In comparison with structurally related cobalt catalysts, it was evident that the presence of the N-2,4-bis(dibenzosuberyl)-6-fluorophenyl groups had a limited effect on catalytic activity but a marked effect on thermal stability.
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Liu T, Liu M, Ma Y, Solan GA, Liang T, Sun WH. Cobalt catalysts bearing ortho‐(4,4'‐dichlorobenzhydryl) substituents and their use in generating narrowly dispersed polyethylene of high linearity. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Tian Liu
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory for Engineering Plastics CHINA
| | - Ming Liu
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory for Engineering Plastics CHINA
| | - Yanping Ma
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory for Engineering Plastics CHINA
| | | | - Tongling Liang
- Institute of Chemistry Chinese Academy of Sciences Key Laboratory for Engineering Plastics CHINA
| | - Wen-Hua Sun
- The Chinese Academy of Sciences Institute of Chemistry No.2, BeiyijieZhongguancun 100190 Beijing CHINA
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Malik AA, Meraz MM, Yang W, Zhang Q, Sage DD, Sun WH. Catalytic Performance of Cobalt(II) Polyethylene Catalysts with Sterically Hindered Dibenzopyranyl Substituents Studied by Experimental and MLR Methods. Molecules 2022; 27:molecules27175455. [PMID: 36080222 PMCID: PMC9458042 DOI: 10.3390/molecules27175455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/14/2022] [Accepted: 08/23/2022] [Indexed: 12/02/2022] Open
Abstract
Given the great importance of cobalt catalysts supported by benchmark bis(imino)pyridine in the (oligo)polymerization, a series of dibenzopyran-incorporated symmetrical 2,6-bis(imino) pyridyl cobalt complexes (Co1–Co5) are designed and prepared using a one-pot template approach. The structures of the resulting complexes are well characterized by a number of techniques. After activation with either methylaluminoxane (MAO) or modified MAO (MMAO), the complexes Co1–Co4 are highly active for ethylene polymerization with a maximum activity of up to 7.36 × 106 g (PE) mol−1 (Co) h−1 and produced highly linear polyethylene with narrow molecular weight distributions, while Co5 is completely inactive under the standard conditions. Particularly, complex Co3 affords polyethylene with high molecular weights of 85.02 and 79.85 kg mol−1 in the presence of MAO and MMAO, respectively. The 1H and 13C NMR spectroscopy revealed the existence of vinyl end groups in the resulting polyethylene, highlighting the predominant involvement of the β-H elimination reaction in the chain-termination process. To investigate the mechanism underlying the variation of catalytic activities as a function of substituents, multiple linear regression (MLR) analysis was performed, showing the key role of open cone angle (θ) and effective net charge (Q) on catalytic activity.
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Affiliation(s)
- Arfa Abrar Malik
- CAS Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Md Mostakim Meraz
- CAS Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenhong Yang
- CAS Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- Advanced Materials Research Center, Petrochemical Research Institute, PetroChina Company Limited, Beijing 102206, China
- Correspondence: (W.Y.); (W.-H.S.); Tel.: +86-10-6255-7955 (W.-H.S.)
| | - Qiuyue Zhang
- CAS Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Desalegn Demise Sage
- CAS Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wen-Hua Sun
- CAS Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
- Correspondence: (W.Y.); (W.-H.S.); Tel.: +86-10-6255-7955 (W.-H.S.)
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Yuan SF, Wang L, Yan Y, Liu T, Flisak Z, Ma Y, Sun WH. 4,4'-Dimethoxybenzhydryl substituent augments performance of bis(imino)pyridine cobalt-based catalysts in ethylene polymerization. RSC Adv 2022; 12:15741-15750. [PMID: 35685715 PMCID: PMC9127841 DOI: 10.1039/d2ra01547a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/17/2022] [Indexed: 11/21/2022] Open
Abstract
A series of cobalt complexes with bis(imino)pyridine derivatives featuring unsymmetrical substitution with bulky groups has been synthesized and characterized. The molecular structures of two representatives have been determined by the single-crystal X-ray diffraction study, revealing distorted tetrahedral geometry with different degrees of steric hindrance imparted by the two inequivalent aryl groups attached to the imine nitrogen atoms. On activation with either MAO or MMAO, these complexes display high activity toward ethylene polymerization, reaching 8.71 × 106 g of PE (mol of Co)−1 h−1 at 60 °C and produce polyethylene of high molecular weight (Mw = 5.27 × 105 g mol−1) and low dispersity. The presence of the methoxy-substituent noticeably enhances the activity of the cobalt catalyst and increases the molecular weight of the resultant polyethylene. Employing ligands with 4,4′-dimethoxybenzhydryl groups, the cobalt precatalysts display high activities toward ethylene polymerization and produce highly linear polyethylenes, the high density polyethylene (HDPE).![]()
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Affiliation(s)
- Shi-Fang Yuan
- The School of Chemistry and Chemical Engineering, Institute of Applied Chemistry, Shanxi University Taiyuan 030006 China
| | - Luyao Wang
- The School of Chemistry and Chemical Engineering, Institute of Applied Chemistry, Shanxi University Taiyuan 030006 China .,Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Yi Yan
- The School of Chemistry and Chemical Engineering, Institute of Applied Chemistry, Shanxi University Taiyuan 030006 China .,Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Tian Liu
- The School of Chemistry and Chemical Engineering, Institute of Applied Chemistry, Shanxi University Taiyuan 030006 China .,Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Zygmunt Flisak
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China .,Faculty of Chemistry, University of Opole Oleska 48 45-052 Opole Poland
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
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Zhang Q, Zuo Z, Ma Y, Liang T, Yang X, Sun WH. Fluorinated 2,6-Bis(arylimino)pyridyliron Complexes Targeting Bimodal Dispersive Polyethylene; probing chain termination pathway via a combined experimental and DFT study. Dalton Trans 2022; 51:8290-8302. [DOI: 10.1039/d2dt00868h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The fluorinated 2,6-bis(arylimino)pyridyl iron (II) complexes, [2-[CMeN{2,4-{(4-FC6H4)2CH}2-6-F}]-6-(CMeNAr)C5H3N]FeCl2 (Ar = 2,6-Me2C6H3 Fe1, 2,6-Et2C6H3 Fe2, 2,6-iPr2C6H3 Fe3, 2,4,6-Me3C6H2 Fe4, and 2,6-Et2-4-MeC6H2 Fe5) and [2-[CMeN{2-{(4-FC6H4)2CH}-4-{(C6H5)CHAr’}-6-F}]-6-(CMeN(2,6-iPr2C6H3))C5H3N] FeCl2 (Ar’ = 3-(4-FC6H4)2CH}2-4-NH2-5-FC6H2 Fe6), being verified with...
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Lin W, Zhang L, Solan GA, Ma Y, Liang T, Sun W. Naphthalenyl‐Substituted α,α′‐Bisimino‐2,3 : 5,6‐Bis(pentamethylene)pyridines as Thermally Robust Supports for Iron Ethylene Polymerization Catalysts. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100595] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Wenhua Lin
- School of Textiles Science and Engineering Jiangnan University Wuxi, Jiangsu 214122 China
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Liping Zhang
- School of Textiles Science and Engineering Jiangnan University Wuxi, Jiangsu 214122 China
| | - Gregory A. Solan
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- Department of Chemistry University of Leicester University Road Leicester LE1 7RH UK
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Wen‐Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
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7
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Singh O, Maji A, Singh A, Singh N, Ghosh K. A new family of complexes derived from bis(imino)pyridine‐type ligands: Crystal structures and bio‐molecular interaction studies. Appl Organomet Chem 2021. [DOI: 10.1002/aoc.6177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ovender Singh
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee India
- Department of Chemistry Chonnam National University Gwangju South Korea
| | - Ankur Maji
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee India
| | - Anshu Singh
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee India
| | - Neetu Singh
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee India
- Department of Chemistry Chonnam National University Gwangju South Korea
| | - Kaushik Ghosh
- Department of Chemistry Indian Institute of Technology Roorkee Roorkee India
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8
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Zhang R, Huang Y, Ma Y, Solan GA, Hu X, Liang T, Sun WH. Thermally resilient cobalt ethylene polymerization catalysts under the joint influence of co-catalyst, gem-dimethyl substitution and ortho-cycloalkyl ring size. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123684] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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9
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Zada M, Guo L, Zhang W, Ma Y, Liang T, Sun W. Rational Design of Cycloheptyl‐Fused Bis(arylimino)pyridyl‐cobalt(II) Precatalysts Adorned with Sterically and Electronically Modified
N
‐Aryls for Enhancing Ethylene Polymerization. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202001120] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Muhammad Zada
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Liwei Guo
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- Beijing Key Laboratory of Clothing Materials R&D and Assessment Beijing Engineering Research Center of Textile Nanofiber School of Materials Science and Engineering Beijing Institute of Fashion Technology Beijing 100029 China
| | - Wenjuan Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- Beijing Key Laboratory of Clothing Materials R&D and Assessment Beijing Engineering Research Center of Textile Nanofiber School of Materials Science and Engineering Beijing Institute of Fashion Technology Beijing 100029 China
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
| | - Wen‐Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China
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10
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Bariashir C, Zhang R, Vignesh A, Ma Y, Liang T, Sun WH. Enhancing Ethylene Polymerization of NNN-Cobalt(II) Precatalysts Adorned with a Fluoro-substituent. ACS OMEGA 2021; 6:4448-4460. [PMID: 33623851 PMCID: PMC7893795 DOI: 10.1021/acsomega.0c05916] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 01/22/2021] [Indexed: 06/12/2023]
Abstract
Unsymmetrical 2-(1-(2,4-dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-alkylphenyl-imino)ethyl)pyridine compounds (Ar = 2,6-Me2C6H3 in L1; 2,6-Et2C6H3 in L2; 2,6- i Pr2C6H3 in L3; 2,4,6-Me3C6H2 in L4; 2,6-Et2-4-Me-C6H2 in L5) were prepared and characterized. The treatment of CoCl2 with the compounds L1-L5 afforded the corresponding cobalt complexes Co1-Co5 in excellent yields. The molecular structures of Co3 and Co4 were determined by single-crystal X-ray diffraction, revealing the distorted-square-pyramidal geometry with three nitrogen atoms and two chlorine atoms around the cobalt center. Compared with previous bis(imino)pyridylcobalt analogues, all of the cobalt precatalysts displayed exceptionally higher activities toward ethylene polymerization with 1.32 × 107 g (PE) mol-1 (Co) h-1 at 60 °C in the presence of a co-catalyst MAO or MMAO. These cobalt catalysts produced highly linear polyethylene (PE) waxes with vinyl end groups and low molecular weight (M w up to 8.23 kg mol-1) along with a relatively lower melting point (all-round T ms < 128 °C). The narrow dispersity of resultant polyethylenes indicated the single-site active species of the catalytic system.
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Affiliation(s)
- Chantsalnyam Bariashir
- Key
Laboratory of Engineering Plastics and Beijing National Laboratory
for Molecular Science, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
- CAS
Research/Education Center for Excellence in Molecular Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Randi Zhang
- Key
Laboratory of Engineering Plastics and Beijing National Laboratory
for Molecular Science, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
- CAS
Research/Education Center for Excellence in Molecular Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Arumugam Vignesh
- Key
Laboratory of Engineering Plastics and Beijing National Laboratory
for Molecular Science, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
| | - Yanping Ma
- Key
Laboratory of Engineering Plastics and Beijing National Laboratory
for Molecular Science, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
| | - Tongling Liang
- Key
Laboratory of Engineering Plastics and Beijing National Laboratory
for Molecular Science, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
| | - Wen-Hua Sun
- Key
Laboratory of Engineering Plastics and Beijing National Laboratory
for Molecular Science, Institute of Chemistry,
Chinese Academy of Sciences, Beijing 100190, China
- CAS
Research/Education Center for Excellence in Molecular Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- State
Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy
of Sciences, Lanzhou 730000, China
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11
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Comparison of the Reactivity and Structures for the Neutral and Cationic Bis(imino)pyridyl Iron and Cobalt Species by DFT Calculations. Catalysts 2020. [DOI: 10.3390/catal10121396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Density Functional Theory (DFT) method was adopted to investigate and compare the reaction mechanisms of ethylene polymerization catalyzed by neutral, cationic bis(imino)pyridyl (PDI) iron and cobalt derivatives. The electronic structure and the oxidation states of the metal center and the PDI ligand were analyzed by taking spin states, natural bond orbital (NBO) charge distribution, etc. into consideration, revealing that the reactivity is closely related to the valence electron numbers instead of the charge numbers. The neutral Co(0) had the lowest reactivity as it possessed the most electrons. During the formation of the cationic Co(+)/Fe(+), one electron was mainly lost from PDI ligand rather than the metal center while the metal center maintained +II valence state through the process. Moreover, a special unsymmetrically bidentate N^N coordination manner was found to provide the deficient metal surroundings with 14e, which may initiate the reactivity of some unsymmetrical species with rich electrons. Finally, an anion [AlMe4]− participating process was proposed to explain the presence of the experimentally observed LCo(+)B(C2H4). A special intermediate, Co(+)B(C2H4) [AlMe4]− with Co in +I and absence of Co–C σ bond, was obtained. These calculation results may provide fundamental information for further understanding and designing the ethylene polymerization catalysts.
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12
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Yuan SF, Fan Z, Yan Y, Ma Y, Han M, Liang T, Sun WH. Achieving polydispersive HDPE by N, N, N-Co precatalysts appended with N-2,4-bis(di(4-methoxyphenyl)methyl)-6-methylphenyl. RSC Adv 2020; 10:43400-43411. [PMID: 35519690 PMCID: PMC9058363 DOI: 10.1039/d0ra09333e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 11/23/2020] [Indexed: 01/15/2023] Open
Abstract
A family of unsymmetrical 2-(2,4-bis(di(4-methoxyphenyl)methyl)-6-MeC6H2N)-6-(1-(arylimino)ethyl)pyridine-cobalt dichloride complexes has been synthesized and characterized by NMR spectroscopy, FT-IR spectroscopy and elemental analysis as well as single crystal X-ray diffraction for Co2 and Co4. Activated with either MAO or MMAO, all the cobalt precatalysts displayed high activities toward ethylene polymerization and produced highly linear polyethylenes with high molecular weights as well as wide polydispersities; for example, the performance using Co1/MAO at 50 °C reached 9.17 × 106 g PE (mol of Co)−1 h−1 with the production polyethylene of molecular weight as high as Mw = 3.14 × 105 g mol−1, Tm = 134.3 °C besides its wide polydispersity of Mw/Mn of 54.6. Besides the terminal vinyl group of the resultant polyethylenes, it is rare for a late-transition metal catalyst to achieve highly linear polyethylenes with not only wide polydispersity but also high molecular weights, being similar to high-density polyethylenes produced using Phillips catalyst. Introducing a practical application of N,N,N-Co precatalysts for highly linear polyethylenes with wide polydispersity and high molecular weights, targeting HDPE using Phillips catalyst.![]()
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Affiliation(s)
- Shi-Fang Yuan
- Institute of Applied Chemistry, Shanxi University Taiyuan 030006 People's Republic of China
| | - Zhe Fan
- Institute of Applied Chemistry, Shanxi University Taiyuan 030006 People's Republic of China .,Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China +86-10-62618239 +86-10-62557955
| | - Yi Yan
- Institute of Applied Chemistry, Shanxi University Taiyuan 030006 People's Republic of China .,Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China +86-10-62618239 +86-10-62557955
| | - Yanping Ma
- Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China +86-10-62618239 +86-10-62557955
| | - Mingyang Han
- Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China +86-10-62618239 +86-10-62557955
| | - Tongling Liang
- Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China +86-10-62618239 +86-10-62557955
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China +86-10-62618239 +86-10-62557955.,State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences Lanzhou 730000 China
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13
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Adjusting Ortho-Cycloalkyl Ring Size in a Cycloheptyl-Fused N,N,N-Iron Catalyst as Means to Control Catalytic Activity and Polyethylene Properties. Catalysts 2020. [DOI: 10.3390/catal10091002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Five examples of bis(arylimino)tetrahydrocyclohepta[b]pyridine dichloroiron(II) complex, [2-{(Ar)N=CMe}-9-{N(Ar)}C10H10N]FeCl2 (Ar = 2-(C5H9)-4,6-(CHPh2)2C6H2Fe1, 2-(C6H11)-4,6-(CHPh2)2C6H2Fe2, 2-(C8H15)-4,6-(CHPh2)2C6H2Fe3, 2-(C12H23)-4,6-(CHPh2)2C6H2Fe4, and 2,6-(C5H9)2-4-(CHPh2)C6H2Fe5), incorporating ortho-pairings based on either benzhydryl/cycloalkyl (ring sizes ranging from 5 to 12) or cyclopentyl/cyclopentyl groups, have been prepared in reasonable yield by employing a simple one-pot template strategy. Each complex was characterized by FT-IR spectroscopy, elemental analysis, and for Fe3 and Fe5 by single crystal X-ray diffraction; pseudo-square pyramidal geometries are a feature of their coordination spheres. On treatment of Fe1–Fe5 with modified methylaluminoxane (MMAO) or methylaluminoxane (MAO), a range in catalytic activities for ethylene polymerization were observed with benzhydryl/cyclopentyl-containing Fe1/MMAO achieving the maximum level of 15.3 × 106 g PE mol−1 (Fe) h−1 at an operating temperature of 70 °C. As a key trend, the activity was found to drop as the ortho-cycloalkyl ring size increased: Fe1C5H9/CHPh2~Fe5C5H9/C5H9 > Fe2C6H11/CHPh2 > Fe3C8H15/CHPh2 > Fe4C12H23/CHPh2. Furthermore, strictly linear polyethylenes (Tm > 126 °C) were formed with molecular weights again dependent on the ortho-cycloalkyl ring size (up to 55.6 kg mol−1 for Fe1/MAO); narrow dispersities were a characteristic of all the polymers (Mw/Mn range: 2.3–4.7), highlighting the well-controlled nature of these polymerizations.
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Zada M, Vignesh A, Suo H, Ma Y, Liu H, Sun WH. NNN-type iron(II) complexes consisting sterically hindered dibenzocycloheptyl group: Synthesis and catalytic activity towards ethylene polymerization. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2020.110981] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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15
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Zhang Q, Wu N, Xiang J, Solan GA, Suo H, Ma Y, Liang T, Sun WH. Bis-cycloheptyl-fused bis(imino)pyridine-cobalt catalysts for PE wax formation: positive effects of fluoride substitution on catalytic performance and thermal stability. Dalton Trans 2020; 49:9425-9437. [PMID: 32589179 DOI: 10.1039/d0dt01876g] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The α,α'-bis(imino)-2,3:5,6-bis(pentamethylene)pyridyl-cobalt(ii) chlorides, [2,3:5,6-{C4H8C(N(2-R1-4-R3-6-R2C6H2))}2C5HN] CoCl2 (R1 = Me, R2 = R3 = CH(p-FPh)2Co1; R1 = Et, R2 = R3 = CH(p-FPh)2Co2; R1 = i-Pr, R2 = R3 = CH(p-FPh)2Co3; R1 = Cl, R2 = R3 = CH(p-FPh)2Co4; R1 = F, R2 = R3 = CH(p-FPh)2Co5; R1 = F, R2 = R3 = CHPh2Co5'', R1 = R2 = Me, R3 = CH(p-FPh)2Co6; R1 = R3 = Me, R2 = CH(p-FPh)2Co7), have been synthesized by a one-pot template reaction of α,α'-dioxo-2,3:5,6-bis(pentamethylene)pyridine, cobalt(ii) chloride and the respective aniline in n-butanol. By contrast, the mixed cobalt(ii) chloride/acetate complex, [2,3:5,6-{C4H8C(N(2-F-4,6-(CH(p-FPh)2)2C6H2))}2C5HN]CoCl(OAc) (Co5'), was isolated when the corresponding template reaction was carried out in acetic acid. Structural characterization of Co4, Co5 and Co5'' revealed distorted square pyramidal geometries while six-coordinate Co5', incorporating a chelating acetate ligand, exhibited a distorted octahedral geometry. On activation with either MAO or MMAO, 2-fluoride-4,6-bis{di(p-fluorophenyl)methyl}-substituted Co5 showed maximum catalytic activity for ethylene polymerization at a high operating temperature of 60 °C (up to 2.1 × 107 g (PE) mol-1 (Co) h-1), producing highly linear (Tms > 121 °C), low molecular weight polyethylene waxes (Mw range: 1.5-5.0 kg mol-1) with narrow dispersity (Mw/Mn range: 1.7-2.9). End-group analysis of the waxes reveals β-H elimination as the dominant chain transfer process.
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Affiliation(s)
- Qiuyue Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ningning Wu
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Junfeng Xiang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Gregory A Solan
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, UK.
| | - Hongyi Suo
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China and State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
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16
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Han M, Zhang Q, Oleynik II, Suo H, Solan GA, Oleynik IV, Ma Y, Liang T, Sun WH. High molecular weight polyethylenes of narrow dispersity promoted using bis(arylimino)cyclohepta[b]pyridine-cobalt catalysts ortho-substituted with benzhydryl & cycloalkyl groups. Dalton Trans 2020; 49:4774-4784. [PMID: 32211662 DOI: 10.1039/d0dt00576b] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
A one-pot template strategy has been utilized to synthesize sterically enhanced bis(imino)cyclohepta[b]pyridine-cobalt(ii) chlorides, [2-{(Ar)N[double bond, length as m-dash]CMe}-9-{N(Ar)}C10H10N]CoCl2 (Ar = 2-(C5H9)-4,6-(CHPh2)2C6H2Co1, 2-(C6H11)-4,6-(CHPh2)2C6H2Co2, 2-(C8H15)-4,6-(CHPh2)2C6H2Co3, 2-(C12H23)-4,6-(CHPh2)2C6H2Co4, 2,6-(C5H9)2-4-(CHPh2)C6H2Co5). All five complexes have been characterized by a combination of FT-IR spectroscopy, elemental analysis and single crystal X-ray diffraction. The molecular structures of Co1, Co3 and Co5 highlight the substantial steric hindrance imparted by the 2-cycloalkyl-6-benzhydryl or 2,6-dicyclopentyl ortho-substitution pattern; distorted square pyramidal geometries are exhibited in each case. On activation with methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), all the complexes (apart from Co4/MAO) were active ethylene polymerization catalysts (up to 3.70 × 106 g PE per mol (Co) per h for Co5/MMAO), operating effectively at temperatures between 50 °C and 60 °C, producing polyethylenes with high molecular weights (up to 589.5 kg mol-1 for Co3/MAO). Furthermore, all polymers were highly linear (Tm > 130 °C) with narrow dispersities (Mw/Mn range: 2.0-3.0). The coexistence of two chain termination pathways, β-H elimination and transfer to aluminum, has been demonstrated using 13C/1H NMR spectroscopy.
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Affiliation(s)
- Mingyang Han
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiuyue Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ivan I Oleynik
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Pr. Lavrentjeva 9, Novosibirsk 630090, Russia.
| | - Hongyi Suo
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Gregory A Solan
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, UK.
| | - Irina V Oleynik
- N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Pr. Lavrentjeva 9, Novosibirsk 630090, Russia.
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China and State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
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17
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Zhang Q, Zhang R, Han M, Yang W, Liang T, Sun WH. 4,4'-Difluorobenzhydryl-modified bis(imino)-pyridyliron(ii) chlorides as thermally stable precatalysts for strictly linear polyethylenes with narrow dispersities. Dalton Trans 2020; 49:7384-7396. [PMID: 32427253 DOI: 10.1039/d0dt01344g] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The 4,4'-difluorobenzhydryl-modified bis(imino)pyridylferrous chlorides, [2-{CMeN(2,6-(4-FC6H4)2CH2-4-t-BuC6H2)}-6-(CMeNAr)C5H3N] FeCl2 (Ar = 2,6-Me2C6H3Fe1, 2,6-Et2C6H3Fe2, 2,6-i-Pr2C6H3Fe3, 2,4,6-Me3C6H2Fe4, 2,6-Et-4-MeC6H2Fe5 and 2,6-(4-FC6H4)2CH2-4-t-BuC6H2Fe6), were synthesized in good yields. All iron complexes were characterized by 1H/19F NMR and elemental analysis, and the molecular structures of representative complexes Fe1 and Fe6 were determined by single crystal X-ray diffraction, which revealed a slightly distorted square pyramid around the iron center. Activated with either MAO or MMAO, Fe1-Fe5 exhibited very high activities (up to 17.2 × 106 g (PE) mol-1 (Fe) h-1 for Fe1/MMAO) toward ethylene polymerization, producing highly linear polyethylenes with narrow dispersities as required by industry and value added PEs. Importantly, the Fe1/MAO maintained an activity of 9.5 × 106 g (PE) mol-1 (Fe) h-1 at 100 °C of operating temperature, making the catalytic system suitable for practical application. Simulation quantitatively revealed the mechanism of the enhanced catalytic performance from the electronic and steric point of view.
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Affiliation(s)
- Qiuyue Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Randi Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mingyang Han
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenhong Yang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. and CAS Research/Education Center for Excellence in Molecular Sciences and International School, University of Chinese Academy of Sciences, Beijing 100049, China and State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China
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18
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Lin W, Zhang L, Suo H, Vignesh A, Yousuf N, Hao X, Sun WH. Synthesis of characteristic polyisoprenes using rationally designed iminopyridyl metal (Fe and Co) precatalysts: investigation of co-catalysts and steric influence on their catalytic activity. NEW J CHEM 2020. [DOI: 10.1039/d0nj00942c] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A series of iminopyridyl ligand-based iron and cobalt complexes are utilized as catalysts in isoprene polymerization, in which the microstructure of resultant polyisoprenes was investigated.
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Affiliation(s)
- Wenhua Lin
- School of Textiles and Clothing
- Jiangnan University
- Wuxi
- China
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science
| | - Liping Zhang
- School of Textiles and Clothing
- Jiangnan University
- Wuxi
- China
| | - Hongyi Suo
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Arumugam Vignesh
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Nighat Yousuf
- CAS Research/Education Center for Excellence in Molecular Sciences
- University of Chinese Academy of Sciences
- Beijing 100049
- China
| | - Xiang Hao
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
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19
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Zhang R, Ma Y, Han M, Solan GA, Pi Y, Sun Y, Sun W. Exceptionally high molecular weight linear polyethylene by using
N,N,N′‐
Co catalysts appended with a
N′
‐2,6‐bis{di(4‐fluorophenyl)methyl}‐4‐nitrophenyl group. Appl Organomet Chem 2019. [DOI: 10.1002/aoc.5157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Randi Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
- CAS Research/Education Center for Excellence in Molecular SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
| | - Mingyang Han
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
- CAS Research/Education Center for Excellence in Molecular SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
| | - Gregory A. Solan
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
- Department of Chemistry, University of LeicesterUniversity Road Leicester LE1 7RH UK
| | - Yaqing Pi
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
| | - Yang Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
| | - Wen‐Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences, Institute of ChemistryChinese Academy of Sciences Beijing 100190 China
- CAS Research/Education Center for Excellence in Molecular SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
- State Key Laboratory for Oxo Synthesis and Selective OxidationLanzhou Institute of Chemical Physics, Chinese Academy of Sciences Lanzhou 730000 China
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20
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Zhang R, Han M, Ma Y, Solan GA, Liang T, Sun WH. Steric and electronic modulation of iron catalysts as a route to remarkably high molecular weight linear polyethylenes. Dalton Trans 2019; 48:17488-17498. [DOI: 10.1039/c9dt03880a] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The depicted N,N,N-iron(ii) chloride precatalysts, upon activation with either MAO or MMAO, not only display excellent thermal stability but are also capable of generating exceptionally high molecular weight linear polyethylenes.
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Affiliation(s)
- Randi Zhang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Mingyang Han
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Yanping Ma
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Gregory A. Solan
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Tongling Liang
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Wen-Hua Sun
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
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