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Wang X, Ma L, Wang X, Zhao W, Liu H, Zhang X, Wang F. Thermal-Robust Phenoxyimine Titanium Catalysts Bearing Bulky Sidearms for High Temperature Ethylene Homo-/Co- Polymerizations. Polymers (Basel) 2024; 16:902. [PMID: 38611160 PMCID: PMC11013879 DOI: 10.3390/polym16070902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 03/21/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2024] Open
Abstract
A family of titanium complexes (Ti1-Ti7) with the general formula LTiCl3, supported by tridentate phenoxyimine [O-NO] ligands (L1-L7) bearing bulky sidearms, were synthesized by treating the corresponding ligands with stoichiometric amount of TiCl4. All the ligands and complexes were well characterized by 1H and 13C NMR spectroscopies, in which ortho- methoxyl groups on N-aryl moieties shifted to downfield, corroborating the successful coordination reaction. Structural optimization by DFT calculations revealed that one of the phenyl groups on dibenzhydryl moiety could form π-π stacking interaction with the salicylaldimine plane, because of which the obtained titanium complexes revealed good thermal stabilities for high-temperature polymerization of ethylene. The thermal robustness of the complexes was closely related to the strength of π-π stacking interactions, which were mainly influenced by the substituents on the dibenzhydryl moieties; Ti1, Ti4 and Ti5 emerged as the three best-performing complexes at 110 °C. With the aid of such π-π stacking interactions, the complexes were also found to be active at >150 °C, although decreased activities were witnessed. Besides homopolymerizations, complexes Ti1-Ti7 were also found to be active for the high-temperature copolymerization of ethylene and 1-octene, but with medium incorporation percentage, demonstrating their medium copolymerization capabilities.
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Affiliation(s)
- Xin Wang
- Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (H.L.); (X.Z.)
- Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
| | - Lishuang Ma
- College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China
| | - Xiaohua Wang
- Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (H.L.); (X.Z.)
- Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
| | - Wenpeng Zhao
- Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (H.L.); (X.Z.)
- Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
| | - Heng Liu
- Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (H.L.); (X.Z.)
- Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
| | - Xuequan Zhang
- Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (H.L.); (X.Z.)
- Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
| | - Feng Wang
- Shandong Provincial College Laboratory of Rubber Material and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China; (X.W.); (W.Z.); (H.L.); (X.Z.)
- Key Laboratory of Rubber-Plastics, Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology, Qingdao 266042, China
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Li F, He J, Song T, Gao W, Mu X, Mu Y. Zirconium Complexes with Bulkier Amine Bis(phenolate) Ligands and Their Catalytic Properties for Ethylene (Co)polymerization. Inorg Chem 2022; 61:6469-6479. [PMID: 35436094 DOI: 10.1021/acs.inorgchem.2c00061] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of new zirconium complexes bearing bulkier amine bis(phenolate) tetradentate ligands, Me2NCH2CH2N{CH2(2-O-3-R-5-tBu-C6H2)}2ZrCl2 [R = CPhMe2 (1); CMePh2 (2); CPh3 (3); Ph (4); 3,5-Me2C6H3 (5); 3,5-tBu2C6H3 (6); 4-tBuC6H4 (7)], were synthesized and characterized by 1H nuclear magnetic resonance (NMR), 13C NMR, and elemental analyses. The molecular structures of complexes 1 and 3 were determined by single-crystal X-ray diffraction analysis. The X-ray crystallography analysis reveals that these complexes display a slightly distorted octahedral geometry around their metal centers. Upon activation with methylaluminoxane (MAO), dry-MAO, MAO/butylated hydroxytoluene (BHT), or AliBu3/CPh3B(C6F5)4, these zirconium complexes exhibit high catalytic activity for ethylene polymerization [up to 1.07 × 107 g PE (mol Zr)-1 h-1] and ethylene/1-hexene copolymerization [up to 2.78 × 107 g polymer (mol Zr)-1 h-1], affording (co)polymers with moderate to high molecular weights and good comonomer incorporations. The zirconium complexes with bulkier R groups show higher catalytic activities and longer lifetimes and produce polymers with higher molecular weights, while the zirconium complexes with aryls as R groups demonstrate relatively good comonomer incorporation ability for the copolymerization reactions. These catalytic systems also show moderate catalytic activities for the polymerization reactions of propylene, 1-hexene, and 1-decene. Upon activation with MAO, the zirconium complexes also show moderate catalytic activities for the copolymerization reaction of ethylene with 3-buten-1-ol (treated with 1 equiv of AliBu3), affording copolymers with the incorporation of 3-buten-1-ol up to 1.05%.
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Affiliation(s)
- Feng Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Jianghao He
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Tingting Song
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Wei Gao
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Xiaoyue Mu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Ying Mu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
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3
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Kumar S, Dholakiya BZ, Jangir R. Role of organometallic complexes in olefin polymerization: a review report. J Organomet Chem 2021. [DOI: 10.1016/j.jorganchem.2021.122066] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Song T, He J, Liang L, Liu N, Li F, Tong X, Mu X, Mu Y. Titanium and zirconium complexes bearing new tridentate [OSO] bisphenolato-based ligands: synthesis, characterization and catalytic properties for alkene polymerization. Dalton Trans 2019; 48:13719-13731. [PMID: 31469372 DOI: 10.1039/c9dt03225h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A number of new sulfur-bridged tridentate [OSO] bisphenolato-based ligand precursors S(2-CH2-4-tBu-6-R-C6H2OH)2 [R = CMe3 (H2L1), CMe2Ph (H2L2), CMePh2 (H2L3), CPh3 (H2L4), and C(p-Tol)3 (H2L5)] were synthesized by reactions of Na2S·9H2O with 2 eq. of the corresponding 2-(bromomethyl)-4-(tert-butyl)-6-R-phenol. Their neutral titanium complexes [S(2-CH2-4-tBu-6-R-C6H2O)2]TiCl2 [R = CMe3 (1), CMe2Ph (2), CMePh2 (3), CPh3 (4), and C(p-Tol)3 (5)] were synthesized in high yields by direct HCl-elimination reactions of TiCl4 with the corresponding ligand precursors in toluene. Ionic titanium complexes [NHEt3][S(2-CH2-4-tBu-6-R-C6H2O)2TiCl3] [R = CMe3 (6), CMePh2 (7)] and [NH2Et2][S(2-CH2-4-tBu-6-R-C6H2O)2TiCl3] [R = CMe3 (8) and CMePh2 (9)] were obtained in high yields from the reactions of TiCl4 with the corresponding ligand precursors in the presence of 2 eq. of triethylamine or diethylamine. Neutral zirconium complexes [S(2-CH2-4-tBu-6-R-C6H2O)2]ZrCl2(THF) [R = CMe2Ph (10·THF), and CMePh2 (11·THF)] were synthesized by reactions of ZrCl4 with 1 eq. of the dilithium salt of the corresponding ligand precursors Li2L in THF. The new titanium and zirconium complexes were characterized by 1H and 13C NMR, IR and elemental analyses. The molecular structures of complexes 4, 6 and 10·THF were determined by single-crystal X-ray diffraction analysis. The X-ray crystallography analysis reveals that titanium complex 4 has a five-coordinating environment surrounding the central metal atom, while the titanium complex 6 and the THF-solvated zirconium complex 10·THF possess a six-coordinating pseudo-octahedral environment around the central metal atom. Upon activation with MAO or AliBu3/Ph3CB(C6F5)4, all these titanium and zirconium complexes exhibit moderate to high catalytic activities for ethylene polymerization and ethylene/1-hexene copolymerization with moderate to high comonomer incorporation, and the ionic titanium complexes 6, 7, 8 and 9 show lower catalytic activity than their corresponding neutral complexes under similar conditions.
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Affiliation(s)
- Tingting Song
- The State Key Laboratory for Supramolecular Structure and Materials, School of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China.
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5
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Graziano BJ, Wile BM, Zeller M. Palladium(II) complexes of a bridging amine bis-(phenolate) ligand featuring κ 2 and κ 3 coordination modes. Acta Crystallogr E Crystallogr Commun 2019; 75:1265-1269. [PMID: 31417804 PMCID: PMC6690448 DOI: 10.1107/s2056989019010454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 07/22/2019] [Indexed: 11/11/2022]
Abstract
Bidentate and tridentate coordination of a 2,4-di-tert-butyl-substituted bridging amine bis-(phenolate) ligand to a palladium(II) center are observed within the same crystal structure, namely di-chlorido-({6,6'-[(ethane-1,2-diylbis(methyl-aza-nedi-yl)]bis-(methyl-ene)}bis-(2,4-di-tert-butyl-phenol))palladium(II) chlorido-(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hy-droxy-phen-yl)meth-yl](meth-yl)amino}-eth-yl)(meth-yl)amino]-meth-yl}phenolato)palladium(II) methanol 1.685-solvate 0.315-hydrate, [PdCl2(C34H56N2O2)][PdCl(C34H55N2O2)]·1.685CH3OH·0.315H2O. Both complexes exhibit a square-planar geometry, with unbound phenol moieties participating in inter-molecular hydrogen bonding with co-crystallized water and methanol. The presence of both κ2 and κ3 coordination modes arising from the same solution suggest a dynamic process in which phenol donors may coordinate or dissociate from the metal center, and offers insight into catalyst speciation throughout Pd-mediated processes. The unit cell contains di-chlorido-({6,6'-[(ethane-1,2-diylbis(methyl-aza-nedi-yl)]bis-(methyl-ene)}bis-(2,4-di-tert-butyl-phenol))palladium(II), {(L 2)PdCl2}, and chlorido-(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hy-droxy-phen-yl)meth-yl](methyl)amino}eth-yl)(meth-yl)amino]-meth-yl}phenolato)palladium(II), {(L 2 X)PdCl}, mol-ecules as well as fractional water and methanol solvent mol-ecules.
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Affiliation(s)
- Brendan J. Graziano
- Donald J. Bettinger Department of Chemistry and Biochemistry, Ohio Northern University, 525 S. Main Street, Ada, Ohio 45810, USA
| | - Bradley M. Wile
- Donald J. Bettinger Department of Chemistry and Biochemistry, Ohio Northern University, 525 S. Main Street, Ada, Ohio 45810, USA
| | - Matthias Zeller
- Department of Chemistry, Purdue University, 560 Oval Dr., West Lafayette, Indiana 47907, USA
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6
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Zhang Y, Qu L, Wang Y, Yuan D, Yao Y, Shen Q. Neutral and Cationic Zirconium Complexes Bearing Multidentate Aminophenolato Ligands for Hydrophosphination Reactions of Alkenes and Heterocumulenes. Inorg Chem 2017; 57:139-149. [DOI: 10.1021/acs.inorgchem.7b02248] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yu Zhang
- Key Laboratory of Organic Synthesis of
Jiangsu Province, College of Chemistry, Chemical Engineering and Materials
Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People’s Republic of China
| | - Liye Qu
- Key Laboratory of Organic Synthesis of
Jiangsu Province, College of Chemistry, Chemical Engineering and Materials
Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People’s Republic of China
| | - Yaorong Wang
- Key Laboratory of Organic Synthesis of
Jiangsu Province, College of Chemistry, Chemical Engineering and Materials
Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People’s Republic of China
| | - Dan Yuan
- Key Laboratory of Organic Synthesis of
Jiangsu Province, College of Chemistry, Chemical Engineering and Materials
Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People’s Republic of China
| | - Yingming Yao
- Key Laboratory of Organic Synthesis of
Jiangsu Province, College of Chemistry, Chemical Engineering and Materials
Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People’s Republic of China
| | - Qi Shen
- Key Laboratory of Organic Synthesis of
Jiangsu Province, College of Chemistry, Chemical Engineering and Materials
Science, Dushu Lake Campus, Soochow University, Suzhou 215123, People’s Republic of China
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7
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Wang B, Zhang J, Zhao H, Huang H, Zheng J, Wang L, Sun J, Zhang Y, Cao Z. Titanium complexes bearing amine bis(phenolate) ligands: Synthesis, structure and catalysis in ring-opening polymerization of lactide. Appl Organomet Chem 2016. [DOI: 10.1002/aoc.3688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Baolong Wang
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Jianing Zhang
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Huanqin Zhao
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - He Huang
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Junpei Zheng
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Liying Wang
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Junmin Sun
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Yongfeng Zhang
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
| | - Zhenzhu Cao
- School of Chemical Engineering; Inner Mongolia University of Technology, Institute of Coal Conversion and Cyclic Economy; Hohhot 010051 People's Republic of China
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8
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Wang KT, Wang YX, Wang B, Li YG, Li YS. Novel zirconium complexes with constrained cyclic β-enaminoketonato ligands: improved catalytic capability toward ethylene polymerization. Dalton Trans 2016; 45:10308-18. [PMID: 27241779 DOI: 10.1039/c6dt01391k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Novel Zr(iv) and Hf(iv) complexes bearing two constrained bulky β-enaminoketonato ligands {[ArN[double bond, length as m-dash]CH-C8H3(CH2)n(R)O]2MBn2, M = Zr or Hf; n = 1, 2 or 3; R = H or C6H5; Ar = C6H5 or C6F5} were synthesized and clearly characterized. X-ray crystal structure analysis reveals that these complexes adopt a distorted octahedral geometry. Compared with non-constrained analogues, the Zr(iv) complexes with a cyclic skeleton exhibited high catalytic activities (up to 16.4 kgPE mmolZr(-1) h(-1)) toward ethylene polymerization at ambient pressure and elevated temperatures. Moreover, the catalytic properties of these complexes could be governed exquisitely by appropriate variation of the N-aryl substituents and the size of the benzocyclane. The Zr(iv) complexes bearing a non-fluorinated N-aryl group yielded oligomers, while the fluorinated analogues bearing a five-membered or six-membered cyclane group produced high molecular weight polyethylenes (33.4-306 kg mol(-1)) under similar conditions on account of the suppression effects on β-H elimination. The Zr(iv) complexes are more active toward ethylene polymerization than the Hf(iv) analogues, and the resulting polymers exhibited higher molecular weight and narrower molecular weight distribution.
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Affiliation(s)
- Kai-Ti Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China. and University of Chinese Academy of Sciences, Changchun Branch, Changchun 130022, China
| | - Yong-Xia Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
| | - Bin Wang
- Tianjin Key Lab Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China.
| | - Yan-Guo Li
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
| | - Yue-Sheng Li
- Tianjin Key Lab Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China. and University of Chinese Academy of Sciences, Changchun Branch, Changchun 130022, China
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Mandal D, Chakraborty D, Ramkumar V, Chand DK. Group 4 alkoxide complexes containing [NNO]-type scaffold: synthesis, structural characterization and polymerization studies. RSC Adv 2016. [DOI: 10.1039/c5ra26721h] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A series of new dinuclear group 4 complexes containing [NNO]-type ligands are utilized as catalysts for polymerization reactions.
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Affiliation(s)
- Dipa Mandal
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai 600 036
- India
| | - Debashis Chakraborty
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai 600 036
- India
| | | | - Dillip Kumar Chand
- Department of Chemistry
- Indian Institute of Technology Madras
- Chennai 600 036
- India
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Kan C, Ma H. Copolymerization of l-lactide and ε-caprolactone catalyzed by mono-and dinuclear salen aluminum complexes bearing bulky 6,6′-dimethylbipheyl-bridge: random and tapered copolymer. RSC Adv 2016. [DOI: 10.1039/c6ra07374c] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mono- and dinuclear salen aluminum complexes bearing a racemic 6,6′-dimethyl-biphenyl bridge could efficiently catalyze the copolymerization of l-LA and ε-CL in the melt, producing practically random and tapered copolymers, respectively.
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Affiliation(s)
- Chao Kan
- Shanghai Key Laboratory of Functional Materials Chemistry and Laboratory of Organometallic Chemistry
- East China University of Science and Technology
- Shanghai 200237
- People's Republic of China
| | - Haiyan Ma
- Shanghai Key Laboratory of Functional Materials Chemistry and Laboratory of Organometallic Chemistry
- East China University of Science and Technology
- Shanghai 200237
- People's Republic of China
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Hwang EY, Park GH, Lee CS, Kang YY, Lee J, Lee BY. Preparation of octahydro- and tetrahydro-[1,10]phenanthroline zirconium and hafnium complexes for olefin polymerization. Dalton Trans 2015; 44:3845-55. [PMID: 25611680 DOI: 10.1039/c4dt03683b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Post-metallocenes were constructed for olefin polymerization using 1,2,3,4,7,8,9,10-octahydro[1,10]phenanthroline and 1,2,3,4-tetrahydro[1,10]phenanthroline derivatives. A series of zirconium complexes - LZrCl2(NHMe2)2 [L = 2,9-H2-C12H12N2 (4), 2,9-Me2-C12H12N2 (5), 2,9-nBu2-C12H12N2 (6), and 2,9-iPr2-C12H12N2 (7)] - and hafnium complexes - LHfCl2(NHMe2)2 [L = 2,9-H2-C12H12N2 (8), 2,9-Me2-C12H12N2 (9), 2,9-nBu2-C12H12N2 (10), and 2,9-iPr2-C12H12N2 (11)] - were synthesized via the reaction of octahydro[1,10]phenanthrolines (2,9-R2-C12H12(NH)2) with (Me2N)2MCl2 (DME). The reaction of 2,9-R2-C12H12(NH)2 with (PhCH2)2ZrCl2 in the presence of a small amount of THF afforded a series of THF adduct analogs, i.e., LZrCl2(THF)2 [L = 2,9-H2-C12H12N2 (12), 2,9-Me2-C12H12N2 (13), 2,9-nBu2-C12H12N2 (14), and 2,9-iPr2-C12H12N2 (15)]. The treatment of 12 and 13 with excess Me3Al resulted in the formation of unexpected complexes, i.e., (η(4)-LAlMe2)ZrCl2(Me) [L = 2,9-H2-C12H12N2 (16) and 2,9-Me2-C12H12N2 (17)], in which the Me2Al unit forms a five-membered ring through binding with the two nitrogen donors and the MeCl2Zr unit slips to an η(4)-binding mode containing the N-C-C-N fragment. The treatment of tetrahydro[1,10]phenanthrolines [2,9-R2-C12NH9(NH)] with M(CH2Ph)4 afforded tribenzyl zirconium complexes LZr(CH2Ph)3 - [L = 2,9-Me2-C12NH9N (18) and 2,9-nBu2-C12NH9N (19)] - and hafnium complexes - LHf(CH2Ph)3 [L = 2,9-Me2-C12NH9N (20), 2,9-nBu2-C12NH9N (21), and 2,9-iPr2-C12NH9N (22)]. The structures of 4, 5, 12, 17, and 22 were elucidated by X-ray crystallography. The newly prepared complexes were screened for ethylene/1-octene copolymerization activity: 12 and 16 were potent catalysts (activities of 74 × 10(6) g mol-Zr h(-1) at ∼120 °C under 30 bar ethylene) for the production of wax-like low-molecular weight polyethylene (Mn: ∼5000), which is widely used in industry.
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Affiliation(s)
- Eun Yeong Hwang
- Department of Molecular Science and Technology, Ajou University, Suwon 443-749, South Korea
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12
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Pola S, Subburu M, Guja R, Muga V, Tao YT. New photocatalyst for allylic aliphatic C–H bond activation and degradation of organic pollutants: Schiff base Ti(iv) complexes. RSC Adv 2015. [DOI: 10.1039/c5ra07616a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Ti(iv) Schiff base complex oxide photocatalysts with high stability for oxidative-cyclization and photodegradation of methylene blue dye under visible light irradiation.
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Affiliation(s)
- Someshwar Pola
- Department of Chemistry
- Nizam College
- Osmania University
- Hyderabad
- India
| | - Mahesh Subburu
- Department of Chemistry
- Nizam College
- Osmania University
- Hyderabad
- India
| | - Ravinder Guja
- Department of Chemistry
- Osmania University
- Hyderabad
- India
| | - Vithal Muga
- Department of Chemistry
- Osmania University
- Hyderabad
- India
| | - Yu-Tai Tao
- Institute of Chemistry
- Academia Sinica
- Taipei
- Republic of China
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