1
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Babaguchi K, Bedi D, Chacon-Teran MA, Findlater M. α-Diimine-mediated C-H functionalization of arenes for aryl-aryl cross-coupling reactions. Org Biomol Chem 2024; 22:2389-2394. [PMID: 38329231 DOI: 10.1039/d3ob01992f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
Easily accessible methods for direct C-H arylation of arenes have been explored in the presence of transition metal catalysts to facilitate C-C bond formation; however, the absence of transition-metal impurities is a significant concern in the preparation of active pharmaceutical ingredients (APIs). Herein, we examine the use of bis(imino)acenaphthene (BIAN) as a potential single-electron transfer initiator in transition metal-free C-C bond-forming reactions. Using this approach, arenes are coupled to several aryl and heteroaryl halides. Based upon preliminary mechanistic evidence and crystallographic probation of an active initiator species, we tentatively propose a potassium-stabilized 'metal-free' radical pathway is in operation.
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Affiliation(s)
- Kotono Babaguchi
- Department of Chemistry & Biochemistry, University of California Merced, Merced, CA 95343, USA.
| | - Deepika Bedi
- Department of Chemistry & Biochemistry, Amity University Punjab, Mohali, Panjab 140306, India
| | - Miguel A Chacon-Teran
- Department of Chemistry & Biochemistry, University of California Merced, Merced, CA 95343, USA.
| | - Michael Findlater
- Department of Chemistry & Biochemistry, University of California Merced, Merced, CA 95343, USA.
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2
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Kenyon P, Leung DWJ, Turner ZR, Buffet JC, O’Hare D. Tuning Polyethylene Molecular Weight Distributions Using Catalyst Support Composition. Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c02604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Philip Kenyon
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - D. W. Justin Leung
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Zoë R. Turner
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Dermot O’Hare
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
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3
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Kenyon P, Leung DJ, Lyu M, Chen C, Turner ZR, Buffet JC, O'Hare D. Controlling the activity of an immobilised molecular catalyst by Lewis acidity tuning of the support. J Catal 2021. [DOI: 10.1016/j.jcat.2021.08.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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4
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Angpanitcharoen P, Lamb JV, Buffet JC, Turner ZR, O'Hare D. Synthesis of zirconocene complexes and their use in slurry-phase polymerisation of ethylene. RSC Adv 2021; 11:11529-11535. [PMID: 35423622 PMCID: PMC8695961 DOI: 10.1039/d1ra01912k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 03/11/2021] [Indexed: 11/26/2022] Open
Abstract
A new family of zirconocene complexes of the type (3-RInd#)2ZrX2 (where Ind# = C6Me5H and R = Me, Et and Ph) have been synthesised and fully characterised. Six new crystal structures have been reported (meso-(3-EtInd#)2ZrBr2, rac-(3-EtInd#)2ZrCl2, rac-(3-EtInd#)2Zr(CH2Ph)2, meso-(3-EtInd#)2Zr(CH2Ph)2, meso-(3-MeInd#)2ZrBr2 and meso-(3-MeInd#)2Zr(CH2Ph)2). The complexes were studied for slurry-phase ethylene polymerisation when immobilised on solid polymethylaluminoxane (sMAO). Variation in the initiation group was found to have greater influence over polymerisation activity for meso-catalysts than rac-catalysts, with meso-alkyl catalysts showing higher polymerisation activities than meso-halide. Below 70 °C, polymerisation activity follows the order sMAO-meso-(3-EtInd#)2Zr(CH2Ph)2, sMAO-meso-(3-EtInd#)2ZrCl2 and sMAO-meso-(3-EtInd#)2ZrBr2 (activities of 657, 561, and 452 kgPE molM−1 h−1 bar−1, respectively). sMAO-meso-(3-EtInd#)2ZrBr2 produces HDPE with the highest molecular weight, followed by sMAO-meso-(3-EtInd#)2ZrCl2 and sMAO-meso-(3-EtInd#)2Zr(CH2Ph)2 (Mw of 503, 406, and 345 kg mol−1, respectively, at 50 °C). sMAO-meso-(3-MeInd#)2ZrBr2 produced HDPE with almost identical molecular weights to sMAO-meso-(3-EtInd#)2ZrCl2 (395 kg mol−1 at 50 °C). A new family of zirconocene complexes of the type (3-RInd#)2ZrX2 (where Ind# = C6Me5H and R = Me, Et and Ph) have been synthesised and fully characterised.![]()
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Affiliation(s)
| | - Jessica V Lamb
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford OX1 3TA UK
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford OX1 3TA UK
| | - Zoë R Turner
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford OX1 3TA UK
| | - Dermot O'Hare
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford OX1 3TA UK
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5
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Williams TJ, Lamb JV, Buffet JC, Khamnaen T, O'Hare D. Synthesis of ultra-high molecular weight poly(ethylene)- co-(1-hexene) copolymers through high-throughput catalyst screening. RSC Adv 2021; 11:5644-5650. [PMID: 35423070 PMCID: PMC8694734 DOI: 10.1039/d1ra00446h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 01/26/2021] [Indexed: 11/21/2022] Open
Abstract
A family of permethylindenyl titanium constrained geometry complexes, Me2SB(R′N,3-RI*)TiX2 ((3-R-η5-C9Me5)Me2Si(R′TiX2)), supported on solid polymethylaluminoxane (sMAO) are investigated as slurry-phase catalysts for ethylene/H2 homopolymerisation and ethylene/1-hexene copolymerisation by high-throughput catalyst screening. Me2SB(tBuN,I*)TiCl2 supported on sMAO [sMAO-Me2SB(tBuN,I*)TiCl2] is responsive to small quantities of H2 (<1.6%), maintaining high polymerisation activities (up to 4900 kgPE molTi−1 h−1 bar−1) and yielding polyethylenes with significantly decreased molecular weight (Mw) (from 2700 to 41 kDa with 1.6% H2). In slurry-phase ethylene/1-hexene copolymerisation studies, a decrease in polymerisation activity and polymer molecular weights compared to ethylene homopolymerisation is observed. Compared to many solid supported system, these complexes all display high 1-hexene incorporation levels up to a maximum incorporation of 14.2 mol% for sMAO-Me2SB(iPrN,I*)TiCl2). We observe a proportionate increase in 1-hexene incorporation with concentration, highlighting the ability of these catalysts to controllably tune the amount of 1-hexene incorporated into the polymer chain to produce linear low-density polyethylene (LLDPE) materials. Permethylindenyl titanium CGCs supported on solid polymethylaluminoxane (sMAO) are investigated as slurry-phase catalysts by high-throughput catalyst screening (copolymerisation of ethylene/1-hexene with incorporation levels up to 14.2 mol%).![]()
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Affiliation(s)
- Thomas J Williams
- Chemistry Research Laboratory, Department of Chemistry, University Oxford 12 Mansfield Road OX1 3TA Oxford UK
| | - Jessica V Lamb
- Chemistry Research Laboratory, Department of Chemistry, University Oxford 12 Mansfield Road OX1 3TA Oxford UK
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University Oxford 12 Mansfield Road OX1 3TA Oxford UK
| | | | - Dermot O'Hare
- Chemistry Research Laboratory, Department of Chemistry, University Oxford 12 Mansfield Road OX1 3TA Oxford UK
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6
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Kilpatrick AFR, Geddes HS, Turner ZR, Buffet JC, Goodwin AL, O'Hare D. Polymethylaluminoxane organic frameworks (sMAOF) – highly active supports for slurry phase ethylene polymerisation. Catal Sci Technol 2021. [DOI: 10.1039/d1cy00767j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A series of modified solid polymethylaluminoxane (sMAO) catalyst supports have been developed for slurry phase ethylene polymerisation, using aryl di-ol modifier groups.
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Affiliation(s)
| | | | - Zoë R. Turner
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Jean-Charles Buffet
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | | | - Dermot O'Hare
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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7
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Angpanitcharoen P, Lamb JV, Turner ZR, Buffet JC, O'Hare D. Synthesis, characterisation and ethylene polymerisation performance of silyl bridged peralkylated bis(indenyl) zirconocenes. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2020.111275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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8
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Leung DWJ, Chen C, Buffet JC, O'Hare D. Correlations of acidity-basicity of solvent treated layered double hydroxides/oxides and their CO 2 capture performance. Dalton Trans 2020; 49:9306-9311. [PMID: 32578630 DOI: 10.1039/d0dt01587c] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The basicity and acidity of solvent-treated layered double hydroxide (ST-LDHs) and their layered double oxides (ST-LDOs) have been fully studied using Hammett titration, in situ FTIR, CO2-TPD and NH3-TPD. Five solvents (ethanol, acetone, isopropanol, ethyl acetate and 1-hexanol) were selected to treat [Mg0.72Al0.28(OH)2](CO3)0.14 (Mg2.5Al-CO3 LDH) and compared with traditional LDH co-precipitated from water. The Brønsted basicity strength of the ST-LDHs and ST-LDOs increased but was accompanied by a decrease in basic site density. In addition, the Lewis acidity of ST-LDOs also changes significantly, with medium strength Lewis acid sites dissapearing after solvent treatment. We found that the CO2 capture capacity of solvent treated LDOs is 50% higher than that of traditional co-precipitated LDO sample. The ethanol treated LDO exhibited the highest CO2 uptake of 1.01 mmol g-1. The observed CO2 capture performance of the ST-LDOs correlates linearly with the ratio of total acid sites to total basic sites.
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Affiliation(s)
- D W Justin Leung
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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9
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Group 4 constrained geometry complexes for olefin (co)polymerisation. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2020.110872] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Lamb JV, Abell JC, McLaren JE, Buffet JC, Turner ZR, O'Hare D. Slurry-phase ethylene polymerisation using group 4 ansa-bridged permethylindenyl complexes supported on polymethylaluminoxane. MOLECULAR CATALYSIS 2020. [DOI: 10.1016/j.mcat.2019.110735] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Lamb JV, Buffet JC, Turner ZR, O’Hare D. Ethylene Polymerization Using Zirconocenes Supported on Pentafluorophenyl-Modified Solid Polymethylaluminoxane. Macromolecules 2020. [DOI: 10.1021/acs.macromol.9b02146] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jessica V. Lamb
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, U.K
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, U.K
| | - Zoë R. Turner
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, U.K
| | - Dermot O’Hare
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, U.K
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12
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Shang S, Hanif A, Sun M, Tian Y, Ok YS, Yu IKM, Tsang DCW, Gu Q, Shang J. Novel M (Mg/Ni/Cu)-Al-CO 3 layered double hydroxides synthesized by aqueous miscible organic solvent treatment (AMOST) method for CO 2 capture. JOURNAL OF HAZARDOUS MATERIALS 2019; 373:285-293. [PMID: 30925388 DOI: 10.1016/j.jhazmat.2019.03.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 02/20/2019] [Accepted: 03/18/2019] [Indexed: 06/09/2023]
Abstract
Layered double hydroxides (LDHs) have been intensively studied in recent years owing to their great potential in CO2 capture. However, the severe aggregation between platelets and low surface area restricted it from exhibiting very high CO2 adsorption capacity and CO2/N2 selectivity. In this research, we for the first time synthesized Ni-Al-CO3 and Cu-Al-CO3 LDHs using aqueous miscible organic solvent treatment (AMOST) method. The as-synthesized materials were evaluated for CO2 adsorption at three different temperatures (50, 80, 120 °C) applicable to post-combustion CO2 capture. Characterized with XRD, N2 adsorption-desorption, TEM, EDX, and TGA, we found the newly synthesized Ni-Al-CO3 LDH showed a nano-flower-like morphology comprising randomly oriented 2D nanoplatelets with both high surface area (249.45 m2/g) and pore volume (0.59 cc/g). Experimental results demonstrated that un-calcined Ni-Al-CO3 LDH is superior in terms of CO2 capture among the three LDHs, with a maximum CO2 adsorption capacity of 0.87 mmol/g and the ideal CO2/N2 selectivity of 166 at 50 °C under 1200 mbar for typical flue gas CO2/N2 composition (CO2:N2 = 15:85, v/v). This is the first report of a delaminated Ni-Al-CO3 LDH showing better CO2 capture performance than the well-reported optimal Mg layered double hydroxide.
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Affiliation(s)
- Shanshan Shang
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, P.R. China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, P.R. China
| | - Aamir Hanif
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, P.R. China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, P.R. China
| | - Mingzhe Sun
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, P.R. China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, P.R. China
| | - Yuanmeng Tian
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, P.R. China
| | - Yong Sik Ok
- Korea Biochar Research Center, O-Jeong Eco-Resilience Institute (OJERI) & Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Iris K M Yu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, PR China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, PR China
| | - Qinfen Gu
- The Australian Synchrotron (ANSTO), 800 Blackburn Rd, Clayton, VIC 3168, Australia
| | - Jin Shang
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Nanshan District, Shenzhen, P.R. China; School of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, P.R. China.
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13
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Hickman GE, Wright CM, Kilpatrick AF, Turner ZR, Buffet JC, O’Hare D. Synthesis, characterisation and slurry phase ethylene polymerisation of rac-(PhBBI*)ZrCl2 immobilised on modified layered double hydroxides. MOLECULAR CATALYSIS 2019. [DOI: 10.1016/j.mcat.2019.02.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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14
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Lamb JV, Buffet JC, Turner ZR, O'Hare D. Group 4 permethylindenyl complexes for slurry-phase polymerisation of ethylene. Polym Chem 2019. [DOI: 10.1039/c8py01796d] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Supported group 4 permethylindenyl based catalysts displayed extremely high ethylene polymerisation activity affording popcorn shaped low molecular weights polyethylenes.
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Affiliation(s)
- Jessica V. Lamb
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Jean-Charles Buffet
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Zoë R. Turner
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Dermot O'Hare
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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15
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Synthesis and characterization of permethylpentalene titanium aryloxide and alkoxide complexes. Polyhedron 2019. [DOI: 10.1016/j.poly.2018.09.068] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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16
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Buffet JC, Turner ZR, O'Hare D. Popcorn-shaped polyethylene synthesised using highly active supported permethylindenyl metallocene catalyst systems. Chem Commun (Camb) 2018; 54:10970-10973. [PMID: 30206626 DOI: 10.1039/c8cc05350b] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Unsymmetrical permethylindenyl bent metallocene complexes have been synthesised and reacted with inorganic solid supports to afford catalysts for the slurry phase polymerisation of ethylene. Those supported on solid polymethylaluminoxane were both highly active catalysts and afforded polymers with a desirable, low aggregation, "popcorn" morphology.
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Affiliation(s)
- Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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17
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Metallocene-Catalyzed Copolymerization of Ethylene and 1-Hexene in the Presence of Graphene/MgAl LDH Nanofiller: Effect on the Activity, SCB, and Thermal Stability. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2018. [DOI: 10.1007/s13369-018-3239-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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18
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Williams TJ, Buffet JC, Turner ZR, O'Hare D. Group 4 permethylindenyl constrained geometry complexes for ethylene polymerisation catalysis. Catal Sci Technol 2018. [DOI: 10.1039/c8cy01374h] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The synthesis and characterisation of six permethylindenyl constrained geometry complexes is reported. Slurry phase ethylene polymerisation studies demonstrate that activities increase with increasing electron donating character of the amido fragment.
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Affiliation(s)
- Thomas J. Williams
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford OX1 3TA
- UK
| | - Jean-Charles Buffet
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford OX1 3TA
- UK
| | - Zoë R. Turner
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford OX1 3TA
- UK
| | - Dermot O'Hare
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford OX1 3TA
- UK
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19
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Cloke FGN, Green JC, Kilpatrick AF, O'Hare D. Bonding in pentalene complexes and their recent applications. Coord Chem Rev 2017. [DOI: 10.1016/j.ccr.2016.12.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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20
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Wright CMR, Ruengkajorn K, Kilpatrick AFR, Buffet JC, O’Hare D. Controlling the Surface Hydroxyl Concentration by Thermal Treatment of Layered Double Hydroxides. Inorg Chem 2017; 56:7842-7850. [PMID: 28653842 DOI: 10.1021/acs.inorgchem.7b00582] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christopher M. R. Wright
- Chemistry Research Laboratory, Department
of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Kanittika Ruengkajorn
- Chemistry Research Laboratory, Department
of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Alexander F. R. Kilpatrick
- Chemistry Research Laboratory, Department
of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department
of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Dermot O’Hare
- Chemistry Research Laboratory, Department
of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
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21
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22
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Fraser DAX, Turner ZR, Buffet JC, O’Hare D. Titanium and Zirconium Permethylpentalene Complexes, Pn*MCpRX, as Ethylene Polymerization Catalysts. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00417] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Duncan A. X. Fraser
- Chemistry Research Laboratory,
Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Zoë R. Turner
- Chemistry Research Laboratory,
Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Jean-Charles Buffet
- Chemistry Research Laboratory,
Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
| | - Dermot O’Hare
- Chemistry Research Laboratory,
Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K
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23
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Buffet JC, Byles CFH, Felton R, Chen C, O'Hare D. Metallocene supported core@LDH catalysts for slurry phase ethylene polymerisation. Chem Commun (Camb) 2016; 52:4076-9. [PMID: 26898544 DOI: 10.1039/c6cc00280c] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the synthesis of solid catalysts based on a zirconocene supported on either silica@AMO-LDH or zeolite@AMO-LDH for the slurry phase polymerisation of ethylene. The hybrid catalysts demonstrate synergistic effects in which the polymerisation activity is up to three times higher than the zirconocene supported on analogous single phase silica or zeolite supports.
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Affiliation(s)
- Jean-Charles Buffet
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Coral F H Byles
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Ryan Felton
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Chunping Chen
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Dermot O'Hare
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
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24
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Chen C, Byles CFH, Buffet JC, Rees NH, Wu Y, O'Hare D. Core-shell zeolite@aqueous miscible organic-layered double hydroxides. Chem Sci 2016; 7:1457-1461. [PMID: 29910903 PMCID: PMC5975924 DOI: 10.1039/c5sc03208c] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 11/13/2015] [Indexed: 11/25/2022] Open
Abstract
We report a general method for the synthesis of core-shell hybrid materials containing a microporous zeolite core with an aqueous miscible organic-layered double hydroxide (AMO-LDH) shell using a simple in situ coprecipitation method. For example, zeolite-HY@AMO-Mg2Al-CO3-LDH contains a 150 nm hierarchical AMO-Mg2Al-CO3-LDH surface coating on zeolite-HY. It exhibits a similar BET surface area (698 m2 g-1) as the parent zeolite-HY but this surface area has been re-allocated between microspores and mesopores. We believe that surface aluminium sites act as nucleation sites for the formation of the LDH coating and so robustly links it into the zeolite lattice. We expect that this new hybrid structure with micropores dominating in the core and mesopores populating the shell will provide a desirable new hybrid structure type for adsorption or catalysis.
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Affiliation(s)
- Chunping Chen
- Chemistry Research Laboratory , Department of Chemistry , University of Oxford , 12 Mansfield Road , Oxford , OX1 3TA , UK . ; Tel: +44 (0)1865 272686
| | - Coral F H Byles
- Chemistry Research Laboratory , Department of Chemistry , University of Oxford , 12 Mansfield Road , Oxford , OX1 3TA , UK . ; Tel: +44 (0)1865 272686
| | - Jean-Charles Buffet
- Chemistry Research Laboratory , Department of Chemistry , University of Oxford , 12 Mansfield Road , Oxford , OX1 3TA , UK . ; Tel: +44 (0)1865 272686
| | - Nicholas H Rees
- Chemistry Research Laboratory , Department of Chemistry , University of Oxford , 12 Mansfield Road , Oxford , OX1 3TA , UK . ; Tel: +44 (0)1865 272686
| | - Yue Wu
- Chemistry Research Laboratory , Department of Chemistry , University of Oxford , 12 Mansfield Road , Oxford , OX1 3TA , UK . ; Tel: +44 (0)1865 272686
| | - Dermot O'Hare
- Chemistry Research Laboratory , Department of Chemistry , University of Oxford , 12 Mansfield Road , Oxford , OX1 3TA , UK . ; Tel: +44 (0)1865 272686
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25
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Wright CMR, Turner ZR, Buffet JC, O'Hare D. Tungsten imido catalysts for selective ethylene dimerisation. Chem Commun (Camb) 2016; 52:2850-3. [DOI: 10.1039/c5cc09386d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A tungsten imido complex W(NDipp)Me3Cl (Dipp = 2,6-iPr-C6H3) is active for the selective dimerisation of ethylene to yield 1-butene under mild conditions. The catalyst supported on polymethylaluminoxane demonstrates higher activity and selectivity.
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Affiliation(s)
| | - Zoë R. Turner
- Chemistry Research Laboratory
- University of Oxford
- Oxford
- UK
| | | | - Dermot O'Hare
- Chemistry Research Laboratory
- University of Oxford
- Oxford
- UK
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26
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Wang X, Fan L, Yuan Y, Du S, Sun Y, Solan GA, Guo CY, Sun WH. Raising the N-aryl fluoride content in unsymmetrical diaryliminoacenaphthylenes as a route to highly active nickel(ii) catalysts in ethylene polymerization. Dalton Trans 2016; 45:18313-18323. [DOI: 10.1039/c6dt03817d] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The title nickel systems, incorporating fluorine content on one N-aryl group, display superior productivity.
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Affiliation(s)
- Xinxin Wang
- School of Chemistry and Chemical Engineering
- University of Chinese Academy of Sciences
- Beijing 100049
- China
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
| | - Linlin Fan
- School of Chemistry and Chemical Engineering
- University of Chinese Academy of Sciences
- Beijing 100049
- China
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
| | - Yichun Yuan
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Shizhen Du
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- China
| | - Yang Sun
- 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
| | - Cun-Yue Guo
- School of Chemistry and Chemical Engineering
- University of Chinese Academy of Sciences
- Beijing 100049
- China
| | - Wen-Hua Sun
- School of Chemistry and Chemical Engineering
- University of Chinese Academy of Sciences
- Beijing 100049
- China
- Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Sciences
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27
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Chen C, Wangriya A, Buffet JC, O'Hare D. Tuneable ultra high specific surface area Mg/Al-CO3 layered double hydroxides. Dalton Trans 2015; 44:16392-8. [PMID: 26308729 DOI: 10.1039/c5dt02641e] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report the synthesis of tuneable ultra high specific surface area Aqueous Miscible Organic solvent-Layered Double Hydroxides (AMO-LDHs). We have investigated the effects of different solvent dispersion volumes, dispersion times and the number of re-dispersion cycles specific surface area of AMO-LDHs. In particular, the effects of acetone dispersion on two different morphology AMO-LDHs (Mg3Al-CO3 AMO-LDH flowers and Mg3Al-CO3 AMO-LDH plates) was investigated. It was found that the amount of acetone used in the dispersion step process can significantly affect the specific surface area of Mg3Al-CO3 AMO-LDH flowers while the dispersion time in acetone is critical factor to obtain high specific surface area Mg3Al-CO3 AMO-LDH plates. Optimisation of the acetone washing steps enables Mg3Al-CO3 AMO-LDH to have high specific surface area up to 365 m(2) g(-1) for LDH flowers and 263 m(2) g(-1) for LDH plates. In addition, spray drying was found to be an effective and practical drying method to increase the specific surface area by a factor of 1.75. Our findings now form the basis of an effective general strategy to obtain ultrahigh specific surface area LDHs.
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Affiliation(s)
- Chunping Chen
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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28
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Buffet JC, Arnold TAQ, Turner ZR, Angpanitcharoen P, O'Hare D. Synthesis and characterisation of permethylindenyl zirconium complexes and their use in ethylene polymerisation. RSC Adv 2015. [DOI: 10.1039/c5ra20465h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report here the synthesis, characterisation and use in solution and slurry phase ethylene polymerisation of new group 4 permethylindenyl complexes.
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Affiliation(s)
- Jean-Charles Buffet
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Thomas A. Q. Arnold
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | - Zoë R. Turner
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
| | | | - Dermot O'Hare
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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