51
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Yuntawattana N, McGuire TM, Durr CB, Buchard A, Williams CK. Indium phosphasalen catalysts showing high isoselectivity and activity in racemic lactide and lactone ring opening polymerizations. Catal Sci Technol 2020. [DOI: 10.1039/d0cy01484b] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Study of a series of phosphasalen indium alkoxide complexes reveals that the substitution pattern at the phosphorus atoms can deliver outstanding isoselectivity with high rates.
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Affiliation(s)
| | | | - Christopher B. Durr
- Chemistry Research Laboratory
- Department of Chemistry
- University of Oxford
- Oxford
- UK
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52
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Shakaroun RM, Jéhan P, Alaaeddine A, Carpentier JF, Guillaume SM. Organocatalyzed ring-opening polymerization (ROP) of functional β-lactones: new insights into the ROP mechanism and poly(hydroxyalkanoate)s (PHAs) macromolecular structure. Polym Chem 2020. [DOI: 10.1039/d0py00125b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The organocatalyzed ROP of some 4-alkoxymethylene-β-propiolactones (BPLORs) towards the formation of the corresponding poly(hydroxyalkanoate)s (PHAs; PBPLORs) is investigated simply using basic organocatalysts of the guanidine (TBD), amidine (DBU) or phosphazene (BEMP) type.
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Affiliation(s)
- Rama M. Shakaroun
- Univ. Rennes
- CNRS
- Institut des Sciences Chimiques de Rennes
- F-35042 Rennes
- France
| | - Philippe Jéhan
- Centre Régional de Mesures Physiques de l'Ouest-CRMPO
- ScanMAT UMS 2001
- Université de Rennes 1
- France
| | - Ali Alaaeddine
- Univ. Libanaise
- Campus Universitaire Rafic Hariri Hadath
- Faculté des Sciences
- Laboratoire de Chimie Médicinale et des Produits Naturels
- Beirut
| | | | - Sophie M. Guillaume
- Univ. Rennes
- CNRS
- Institut des Sciences Chimiques de Rennes
- F-35042 Rennes
- France
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53
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Normand AT, Malacea-Kabbara R, Lapenta R, Dajnak A, Richard P, Cattey H, Bolley A, Grassi A, Milione S, Auffrant A, Dagorne S, Le Gendre P. Phosphasalen group IV metal complexes: synthesis, characterization and ring opening polymerization of lactide. Dalton Trans 2020; 49:6989-7004. [DOI: 10.1039/d0dt00972e] [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
A series of discrete mononuclear neutral and cationic phosphasalen Ti and Zr complexes has been isolated and characterized. For the first time, a cationic group IV metal complex was found active in the ROP of LA.
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54
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Wang Y, Han Y, Zhang L. Binary catalytic system for homo- and block copolymerization of ε-caprolactone with δ-valerolactone. RSC Adv 2020; 10:25979-25987. [PMID: 35518598 PMCID: PMC9055323 DOI: 10.1039/d0ra04974c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 06/30/2020] [Indexed: 12/28/2022] Open
Abstract
The combined interaction of 2,3,6,7-tetrahydro-5H-thiazolo[3,2-a] pyrimidine (ITU) as the organocatalytic nucleophile with YCl3 as Lewis acid cocatalyst, generating ITU/YCl3, was employed for homo- and copolymerization of CL with VL.
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Affiliation(s)
- Yan Wang
- The Center of Analysis and Test
- Shanxi Normal University
- Linfen 041004
- P. R. China
| | - Yongle Han
- School of Chemistry & Material Science
- Shanxi Normal University
- Linfen 041004
- P. R. China
| | - Lifang Zhang
- The Center of Analysis and Test
- Shanxi Normal University
- Linfen 041004
- P. R. China
- School of Chemistry & Material Science
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55
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Nifant’ev I, Ivchenko P. DFT Modeling of Organocatalytic Ring-Opening Polymerization of Cyclic Esters: A Crucial Role of Proton Exchange and Hydrogen Bonding. Polymers (Basel) 2019; 11:E2078. [PMID: 31842423 PMCID: PMC6961033 DOI: 10.3390/polym11122078] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 12/05/2019] [Accepted: 12/11/2019] [Indexed: 01/17/2023] Open
Abstract
Organocatalysis is highly efficient in the ring-opening polymerization (ROP) of cyclic esters. A variety of initiators broaden the areas of organocatalysis in polymerization of different monomers, such as lactones, cyclic carbonates, lactides or gycolides, ethylene phosphates and phosphonates, and others. The mechanisms of organocatalytic ROP are at least as diverse as the mechanisms of coordination ROP; the study of these mechanisms is critical in ensuring the polymer compositions and architectures. The use of density functional theory (DFT) methods for comparative modeling and visualization of organocatalytic ROP pathways, in line with experimental proof of the structures of the reaction intermediates, make it possible to establish these mechanisms. In the present review, which continues and complements our recent manuscript that focused on DFT modeling of coordination ROP, we summarized the results of DFT modeling of organocatalytic ROP of cyclic esters and some related organocatalytic processes, such as polyester transesterification.
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Affiliation(s)
- Ilya Nifant’ev
- Chemistry Department, M.V. Lomonosov Moscow State University, 1 Leninskie Gory Str., Building 3, 119991 Moscow, Russia
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
| | - Pavel Ivchenko
- Chemistry Department, M.V. Lomonosov Moscow State University, 1 Leninskie Gory Str., Building 3, 119991 Moscow, Russia
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
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56
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Li H, Shakaroun RM, Guillaume SM, Carpentier J. Recent Advances in Metal‐Mediated Stereoselective Ring‐Opening Polymerization of Functional Cyclic Esters towards Well‐Defined Poly(hydroxy acid)s: From Stereoselectivity to Sequence‐Control. Chemistry 2019; 26:128-138. [DOI: 10.1002/chem.201904108] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Indexed: 01/18/2023]
Affiliation(s)
- Hui Li
- Institut des Sciences Chimiques de Rennes, UMR 6226 Univ. Rennes, CNRS 35042 Rennes France
| | - Rama M. Shakaroun
- Institut des Sciences Chimiques de Rennes, UMR 6226 Univ. Rennes, CNRS 35042 Rennes France
| | - Sophie M. Guillaume
- Institut des Sciences Chimiques de Rennes, UMR 6226 Univ. Rennes, CNRS 35042 Rennes France
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57
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Anyushin AV, Kondinski A, Parac-Vogt TN. Hybrid polyoxometalates as post-functionalization platforms: from fundamentals to emerging applications. Chem Soc Rev 2019; 49:382-432. [PMID: 31793568 DOI: 10.1039/c8cs00854j] [Citation(s) in RCA: 200] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Polyoxometalates (POMs) represent an important group of metal-oxo nanoclusters, typically comprised of early transition metals in high oxidation states (mainly V, Mo and W). Many plenary POMs exhibit good pH, solvent, thermal and redox stability, which makes them attractive components for the design of covalently integrated hybrid organic-inorganic molecules, herein referred to as hybrid-POMs. Until now, thousands of organic hybrid-POMs have been reported; however, only a small fraction can be further functionalized using other organic molecules or metal cations. This emerging class of 'post-functionalizable' hybrid-POMs constitute a valuable modular platform that permits coupling of POM properties with different organic and metal cation functionalities, thereby expanding the key physicochemical properties that are relevant for application in (photo)catalysis, bioinorganic chemistry and materials science. The post-functionalizable hybrid-POM platforms offer an opportunity to covalently link multi-electron redox responsive POM cores with virtually any (bio)organic molecule or metal cation, generating a wide range of materials with tailored properties. Over the past few years, these materials have been showcased in the preparation of framework materials, functional surfaces, surfactants, homogeneous and heterogeneous catalysts and light harvesting materials, among others. This review article provides an overview on the state of the art in POM post-functionalization and highlights the key design and structural features that permit the discovery of new hybrid-POM platforms. In doing so, we aim to make the subject more comprehensible, both for chemists and for scientists with different materials science backgrounds interested in the applications of hybrid (POM) materials. The review article goes beyond the realms of polyoxometalate chemistry and encompasses emerging research domains such as reticular materials, surfactants, surface functionalization, light harvesting materials, non-linear optics, charge storing materials, and homogeneous acid-base catalysis among others.
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58
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Nifant’ev I, Ivchenko P. Coordination Ring-Opening Polymerization of Cyclic Esters: A Critical Overview of DFT Modeling and Visualization of the Reaction Mechanisms. Molecules 2019; 24:E4117. [PMID: 31739538 PMCID: PMC6891794 DOI: 10.3390/molecules24224117] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/09/2019] [Accepted: 11/12/2019] [Indexed: 01/29/2023] Open
Abstract
Ring-opening polymerization (ROP) of cyclic esters (lactones, lactides, cyclic carbonates and phosphates) is an effective tool to synthesize biocompatible and biodegradable polymers. Metal complexes effectively catalyze ROP, a remarkable diversity of the ROP mechanisms prompted the use of density functional theory (DFT) methods for simulation and visualization of the ROP pathways. Optimization of the molecular structures of the key reaction intermediates and transition states has allowed to explain the values of catalytic activities and stereocontrol events. DFT computation data sets might be viewed as a sound basis for the design of novel ROP catalysts and cyclic substrates, for the creation of new types of homo- and copolymers with promising properties. In this review, we summarized the results of DFT modeling of coordination ROP of cyclic esters. The importance to understand the difference between initiation and propagation stages, to consider the possibility of polymer-catalyst coordination, to figure out the key transition states, and other aspects of DFT simulation and visualization of ROP have been also discussed in our review.
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Affiliation(s)
- Ilya Nifant’ev
- Chemistry Department, M.V. Lomonosov Moscow State University, 1 Leninskie Gory Str., Building 3, 119991 Moscow, Russia
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
| | - Pavel Ivchenko
- Chemistry Department, M.V. Lomonosov Moscow State University, 1 Leninskie Gory Str., Building 3, 119991 Moscow, Russia
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
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59
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Diteepeng N, Buffet JC, Turner ZR, O'Hare D. Constrained geometry scandium permethylindenyl complexes for the ring-opening polymerisation of l- and rac-lactide. Dalton Trans 2019; 48:16099-16107. [PMID: 31617518 DOI: 10.1039/c9dt03450a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The synthesis and characterisation of constrained geometry scandium permethylindenyl chloride, aryloxide and borohydride complexes Me2SB(tBuN,I*)Sc(Cl)(THF) (1), Me2SB(tBuN,I*)Sc(O-2,6-iPr-C6H3)(THF) (2), Me2SB(tBuN,I*)Sc(O-2,4-tBu-C6H3)(THF) (3) and Me2SB(tBuN,I*)Sc(BH4)(THF) (4) are reported. The activity of complexes 1-4 as initiators for the ring-opening polymerisation (ROP) of l- and rac-lactide is presented. The ROP of l- and rac-lactide using complexes 2 and 3 show first-order dependence on monomer concentration, and produced isotactic polylactide (PLA) and moderately heterotactic PLA (Pr = 0.68-0.72), respectively. Good agreement between experimental and theoretical molecular weights of PLA (Mn) and relatively narrow dispersities (Mw/Mn < 1.20) were obtained. Complex 4 showed higher activity for ROP of l- and rac-lactide than 2 or 3, with second-order dependence on monomer concentrations. However, poorly controlled molecular weights and lower heteroselectivity (Pr = 0.61-0.67) were observed. The effect of temperature and catalyst concentration for the ROP of l-lactide using 2 and 3 was also studied.
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Affiliation(s)
- Nichabhat Diteepeng
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Jean-Charles Buffet
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Zoë R Turner
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
| | - Dermot O'Hare
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, OX1 3TA Oxford, UK.
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60
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Affiliation(s)
- Dylan J. Walsh
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Michael G. Hyatt
- Department of Chemistry, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Susannah A. Miller
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Damien Guironnet
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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61
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Improvement in zinc complexes bearing Schiff base in ring-opening polymerization of ε-caprolactone: A five-membered ring system. POLYMER 2019. [DOI: 10.1016/j.polymer.2019.121812] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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62
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Chotard F, Lapenta R, Bolley A, Trommenschlager A, Balan C, Bayardon J, Malacea-Kabbara R, Bonnin Q, Bodio E, Cattey H, Richard P, Milione S, Grassi A, Dagorne S, Le Gendre P. Phenoxyamidine Zn and Al Complexes: Synthesis, Characterization, and Use in the Ring-Opening Polymerization of Lactide. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00501] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Florian Chotard
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Rosita Lapenta
- Institut de Chimie de Strasbourg (UMR-CNRS 7177), Université de Strasbourg, F-67081 Strasbourg cedex, France
- Dipartimento di Chimica e Biologia, Università degli Studi di Salerno, via Giovanni Paolo II, 132-84084 Fisciano (SA), Italy
| | - Anaëlle Bolley
- Institut de Chimie de Strasbourg (UMR-CNRS 7177), Université de Strasbourg, F-67081 Strasbourg cedex, France
| | - Audrey Trommenschlager
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Cédric Balan
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Jérôme Bayardon
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Raluca Malacea-Kabbara
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Quentin Bonnin
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Ewen Bodio
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Hélène Cattey
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Philippe Richard
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
| | - Stefano Milione
- Dipartimento di Chimica e Biologia, Università degli Studi di Salerno, via Giovanni Paolo II, 132-84084 Fisciano (SA), Italy
| | - Alfonso Grassi
- Dipartimento di Chimica e Biologia, Università degli Studi di Salerno, via Giovanni Paolo II, 132-84084 Fisciano (SA), Italy
| | - Samuel Dagorne
- Institut de Chimie de Strasbourg (UMR-CNRS 7177), Université de Strasbourg, F-67081 Strasbourg cedex, France
| | - Pierre Le Gendre
- Institut de Chimie Moléculaire de l’Université de Bourgogne (ICMUB, UMR-CNRS 6302), Université Bourgogne Franche-Comté 25000 Besançon, France
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63
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Ren C, Zhu X, Zhao N, Shen Y, Chen L, Liu S, Li Z. Polystyrene beads supported phosphazene superbase as recyclable organocatalyst for ring-opening polymerization of δ-valerolactone. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.07.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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64
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Wei C, Han B, Zheng D, Zheng Q, Liu S, Li Z. Aluminum Complexes Bearing Bidentate Amido–Phosphine Ligands for Ring-Opening Polymerization of ε-Caprolactone: Steric Effect on Coordination Chemistry and Reactivity. Organometallics 2019. [DOI: 10.1021/acs.organomet.9b00502] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Chuanzhi Wei
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department; College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People’s Republic of China
| | - Binghao Han
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department; College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People’s Republic of China
| | - Dejuan Zheng
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department; College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People’s Republic of China
| | - Quande Zheng
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department; College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People’s Republic of China
| | - Shaofeng Liu
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department; College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People’s Republic of China
| | - Zhibo Li
- Key Laboratory of Biobased Polymer Materials, Shandong Provincial Education Department; College of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, People’s Republic of China
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65
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Zhao Y, Wang Y, Zhou X, Xue Z, Wang X, Xie X, Poli R. Oxygen‐Triggered Switchable Polymerization for the One‐Pot Synthesis of CO
2
‐Based Block Copolymers from Monomer Mixtures. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201906140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yajun Zhao
- School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Yong Wang
- School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Xingping Zhou
- School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Zhigang Xue
- School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Xianhong Wang
- Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied Chemistry, CAS Changchun 130022 P. R. China
| | - Xiaolin Xie
- School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China
| | - Rinaldo Poli
- Laboratoire de Chimie de Coordination (LCC-CNRS) Université de Toulouse UPS, INPT 205, route de Narbonne 31077 Toulouse France
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66
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Zhao Y, Wang Y, Zhou X, Xue Z, Wang X, Xie X, Poli R. Oxygen-Triggered Switchable Polymerization for the One-Pot Synthesis of CO 2 -Based Block Copolymers from Monomer Mixtures. Angew Chem Int Ed Engl 2019; 58:14311-14318. [PMID: 31282122 DOI: 10.1002/anie.201906140] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Indexed: 02/02/2023]
Abstract
Switchable polymerization provides the opportunity to regulate polymer sequence and structure in a one-pot process from mixtures of monomers. Herein we report the use of O2 as an external stimulus to switch the polymerization mechanism from the radical polymerization of vinyl monomers mediated by (Salen)CoIII -R [Salen=N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamine; R=alkyl] to the ring-opening copolymerization (ROCOP) of CO2 /epoxides. Critical to this process is unprecedented monooxygen insertion into the Co-C bond, as rationalized by DFT calculations, leading to the formation of (Salen)CoIII -O-R as an active species to initiate ROCOP. Diblock poly(vinyl acetate)-b-polycarbonate could be obtained by ROCOP of CO2 /epoxides with preactivation of (Salen)Co end-capped poly(vinyl acetate). Furthermore, a poly(vinyl acetate)-b-poly(methyl acrylate)-b-polycarbonate triblock copolymer was successfully synthesized by a (Salen)cobalt-mediated sequential polymerization with an O2 -triggered switch in a one-pot process.
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Affiliation(s)
- Yajun Zhao
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Yong Wang
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Xingping Zhou
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Zhigang Xue
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Xianhong Wang
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, CAS, Changchun, 130022, P. R. China
| | - Xiaolin Xie
- School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Rinaldo Poli
- Laboratoire de Chimie de Coordination (LCC-CNRS), Université de Toulouse, UPS, INPT, 205, route de Narbonne, 31077, Toulouse, France
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67
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Su Y, Chiu T, Liu Y, Lin P, Ko B. Significant enhancement of catalytic properties in mononuclear yttrium complexes by nitrophenolate‐type ligands: Synthesis, structure, and catalysis for lactide polymerization. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/pola.29468] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Yu‐Chia Su
- Department of ChemistryNational Chung Hsing University Taichung 402 Taiwan
| | - Ting‐Yu Chiu
- Department of ChemistryNational Chung Hsing University Taichung 402 Taiwan
| | - Yun‐Ting Liu
- Department of ChemistryNational Chung Hsing University Taichung 402 Taiwan
| | - Po‐Heng Lin
- Department of ChemistryNational Chung Hsing University Taichung 402 Taiwan
| | - Bao‐Tsan Ko
- Department of ChemistryNational Chung Hsing University Taichung 402 Taiwan
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68
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Lai A, Hern ZC, Diaconescu PL. Switchable Ring‐Opening Polymerization by a Ferrocene Supported Aluminum Complex. ChemCatChem 2019. [DOI: 10.1002/cctc.201900747] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Amy Lai
- Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
| | - Zachary C. Hern
- Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
| | - Paula L. Diaconescu
- Department of Chemistry and Biochemistry University of California, Los Angeles 607 Charles E. Young Drive East Los Angeles CA 90095 USA
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69
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Chumsaeng P, Haesuwannakij S, Virachotikul A, Phomphrai K. Random copolymerization of
l
‐lactide and ε‐caprolactone by aluminum alkoxide complexes supported by N
2
O
2
bis(phenolate)‐amine ligands. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/pola.29425] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Phongnarin Chumsaeng
- Department of Chemistry, Faculty of ScienceMahidol University Ratchathewi, Bangkok 10400 Thailand
| | - Setsiri Haesuwannakij
- Department of Materials Science and Engineering, School of Molecular Science and EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC) Wang Chan, Rayong 21210 Thailand
| | - Arnut Virachotikul
- Department of Materials Science and Engineering, School of Molecular Science and EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC) Wang Chan, Rayong 21210 Thailand
| | - Khamphee Phomphrai
- Department of Materials Science and Engineering, School of Molecular Science and EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC) Wang Chan, Rayong 21210 Thailand
- Research Network of NANOTEC‐VISTEC on Nanotechnology for EnergyVidyasirimedhi Institute of Science and Technology Wang Chan, Rayong 21210 Thailand
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70
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Salalens and Salans Derived from 3‐Aminopyrrolidine: Aluminium Complexation and Lactide Polymerisation. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900417] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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71
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Novel aluminum complexes bearing 2-(aminomethylene)malonate ligands with high efficiency and controllability in ring-opening polymerization of ε-caprolactone. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2019.03.055] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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72
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Shen Y, Shepard SM, Reed CJ, Diaconescu PL. Zirconium complexes supported by a ferrocene-based ligand as redox switches for hydroamination reactions. Chem Commun (Camb) 2019; 55:5587-5590. [PMID: 31020301 DOI: 10.1039/c9cc01076a] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The synthesis of (thiolfan*)Zr(NEt2)2 (thiolfan* = 1,1'-bis(2,4-di-tert-butyl-6-thiophenoxy)ferrocene) and its catalytic activity for intramolecular hydroamination are reported. In situ oxidation and reduction of the metal complex results in reactivity towards different substrates. The reduced form of (thiolfan*)Zr(NEt2)2 catalyzes hydroamination reactions of primary aminoalkenes, whereas the oxidized form catalyzes hydroamination reactions of secondary aminoalkenes.
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Affiliation(s)
- Yi Shen
- Department of Chemistry & Biochemistry, University of California, Los Angeles, USA.
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73
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Lu WY, Wu KH, Chen HY, Lin CC. Synthesis and Characterization of N,N,O-Tridentate Aminophenolate Zinc Complexes and Their Catalysis in the Ring-Opening Polymerization of Lactides. Front Chem 2019; 7:189. [PMID: 31024885 PMCID: PMC6459900 DOI: 10.3389/fchem.2019.00189] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 03/12/2019] [Indexed: 12/14/2022] Open
Abstract
A series of aminophenolate ligands with various pendant groups and associated ethyl Zn complexes were synthesized and studied as catalysts for the ring-opening polymerization (ROP) of lactides (LAs). The thiophenylmethyl group (L4ZnEt) increased the catalytic activity more than the benzyl group (L1ZnEt) did, and 2-fluorobenzyl (L3ZnEt) and 2-methoxybenzyl (L2ZnEt) groups had the opposite effect. In addition, the LA polymerization mechanism proved by Nuclear Magnetic Resonance and Density Function Theory was that LA was attracted by H···O bond of an α-hydrogen of the LA molecule and the phenoxyl oxygen of the catalyst. After the dissociation of amino group from the Zn atom, the benzyl alcohol initiated LA without replacing the ethyl group of Zn complex. It is the first case where the ethyl group is regarded as a ligand and cannot be replaced by benzyl alcohol, and this information is very important for the mechanism study of ROP.
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Affiliation(s)
- Wei-Yi Lu
- Department of Chemistry, National Chung Hsing University, Taichung, Taiwan
| | - Kuo-Hui Wu
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Hsuan-Ying Chen
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Chu-Chieh Lin
- Department of Chemistry, National Chung Hsing University, Taichung, Taiwan
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74
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Ligny R, Guillaume SM, Carpentier JF. Yttrium-Mediated Ring-Opening Copolymerization of Oppositely Configurated 4-Alkoxymethylene-β-Propiolactones: Effective Access to Highly Alternated Isotactic Functional PHAs. Chemistry 2019; 25:6412-6424. [PMID: 30779394 DOI: 10.1002/chem.201900413] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 02/18/2019] [Indexed: 01/04/2023]
Abstract
The ring-opening copolymerization (ROCOP) of functional 4-alkoxymethylene-β-propiolactones (BPLOR s) by yttrium-bisphenolate complexes was investigated. The ROCOP of equimolar mixtures of BPLOR s of opposite configurations, namely (R)-BPLOR1 /(S)-BPLOR2 [R1 , R2 =OMe, OAllyl, OCH2 Ph (=OBn), OSiMe2 tBu (=OTBDMS)], by the syndioselective Y{ONOOcum }/iPrOH catalyst/initiator system affords P(HBOR1 -alt-HBOR2 ) copolymers with high alternation degrees (altern.=89-94 %), as determined by comprehensive kinetic, 13 C{1 H} NMR spectroscopy, MALDI-ToF MS and ESI MS/MS fragmentation studies. The ROCOP of the (R)-BPLOMe /(S)-BPLOTBDMS combination, featuring a large difference in the substituents' bulkiness, constitutes the only observed exception to this trend (altern.=64 %). On the other hand, the isoselectivity of the Y{ONNOCl }/iPrOH catalyst/initiator system has been exploited to generate, in a one-pot/one-step procedure, original mixtures of isotactic poly(hydroxyalkanoate)s (PHAs). This system efficiently transforms equimolar mixtures of (R)-BPLOAll /(S)-BPLOMe into a 1:1 mixture of the corresponding isotactic iso-(R)-PHBOAll and iso-(S)-PHBOMe homopolymers; almost no copolymerization defects are observed. This new approach has been extended successfully to the ROCOP of equimolar mixtures of racemic monomers, rac-BPLOAll /rac-BPLOMe .
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Affiliation(s)
- Romain Ligny
- Univ. Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, 35042, Rennes, France
| | - Sophie M Guillaume
- Univ. Rennes, CNRS, Institut des Sciences Chimiques de Rennes, UMR 6226, 35042, Rennes, France
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75
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Dharmaratne NU, Pothupitiya JU, Kiesewetter MK. The mechanistic duality of (thio)urea organocatalysts for ring-opening polymerization. Org Biomol Chem 2019; 17:3305-3313. [PMID: 30834919 DOI: 10.1039/c8ob03174f] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Among the various catalysts for ROP, H-bonding organocatalysts stand out in the precise level of reaction control they are able to render during ROP. The H-bonding class of organocatalysts are thought to effect ROP via dual activation of both monomer and chain end. (Thio)urea mediated ROP has experienced a renaissance as a new polymerization mechanism - mediated by imidate or thioimidate species - facilitates new modes of reactivity and new synthetic abilities. Indeed, the urea class of H-bond donors has been shown to be more active than their corresponding thioureas. The imidate mechanism remains highly active in polar solvents and exhibits remarkable control - and 'living' behavior - under solvent-free conditions, and a broad range of temperatures is accessible. The advancements in synthetic abilities have all evolved through a greater understanding of reaction mechanism. Through the continued synergistic advances of catalysis and material, the (thio)urea class of catalyst can find use in a host of potential applications, research and industrial environments.
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76
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Ghosh S, Nguyen TN, Thi TT, Mejía E. Re-evaluation of the ring-opening polymerization of ε-caprolactone catalyzed by dialkylmagnesium reagents. Eur Polym J 2019. [DOI: 10.1016/j.eurpolymj.2018.12.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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77
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Hardouin Duparc V, Dimeck C, Schaper F. Replacing sulfonate by carboxylate: application of pyridyliminocarboxylato copper(II) complexes in rac-lactide polymerization and Chan–Evans–Lam coupling. CAN J CHEM 2019. [DOI: 10.1139/cjc-2018-0402] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Copper(II) complexes carrying pyridylmethyleneaminobenzoate or –propanoate ligands, LCuX, were prepared in one-pot reactions from pyridinecarboxaldehyde, aminobenzoic acid or β-alanine, and CuX2 (X = Cl, NO3, OAc, or OTf). All complexes were characterized by single-crystal X-ray diffraction studies and formed either dimers, tetramers, or coordination polymers. Attempted preparation of the respective alkoxide complexes, LCu(OR), was unsuccessful, but use of LCuX/NaOMe mixtures in rac-lactide polymerization indicated under some conditions coordination–insertion polymerization via a copper alkoxide as the mechanism. The complexes performed poorly in rac-lactide polymerization, showing low activities (12 h to completion at 140 °C), low to moderate heterotacticity (Pr = 0.6–0.8), and poor polymer molecular weight control (intramolecular transesterification). They were competent catalysts for Chan–Evans–Lam couplings with phenylboronic acid, without any indication of side reactions such as deboration or aryl homocoupling. The complexes were active in undried methanol, without addition of base, ligand, or molecular sieves. Aniline, n-octylamine, and cyclohexylamine were coupled quantitatively under identical reaction conditions. There is only little influence of the anion on activities (less than a factor of 2) but a strong influence on induction periods. The complexes were not active in CEL coupling with alcohols, phenols, or alkylboronic acids.
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Affiliation(s)
- Valérie Hardouin Duparc
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
| | - Clémentine Dimeck
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
| | - Frank Schaper
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
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78
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Remote coordination approach for electronic tuning of a rhodium(I)-N-heterocyclic carbene (NHC)-complex. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2019.01.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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79
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Wei J, Diaconescu PL. Redox-Switchable Ring-Opening Polymerization with Ferrocene Derivatives. Acc Chem Res 2019; 52:415-424. [PMID: 30707548 DOI: 10.1021/acs.accounts.8b00523] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Switchable catalysts incorporate stimuli-responsive features and allow synthetic tasks that are difficult or impossible to accomplish in other ways. They mimic biological processes in that they can provide both spatial and temporal control, unlike most reactions promoted by human-made catalysts that usually occur according to carefully optimized conditions. In the area of switchable catalysis, redox-switchable ring-opening polymerization (ROP) has attracted much attention, emerging as a powerful strategy for the development of environmentally friendly biodegradable copolymers, especially those containing blocks with complementary properties. Controlling the sequence and regularity of each copolymeric building block can affect the material properties significantly since they are directly related to the respective microstructures. Such control can be exerted with a well-designed redox-switchable catalyst by timing the oxidation and reduction events. In highly selective systems, one form of the catalyst reacts with a monomer until the redox state of the catalyst is altered, at which point the altered state of the catalyst reacts with another monomer. The reaction time may be varied from one cycle to another to generate various designer multiblock copolymers. The first instance of redox-mediated ROP was described by N. Long and co-workers in 2006. This example, as well as many early reported redox-switchable catalysts, could only achieve an on/off switch of activity toward a single monomer or substrate. However, our efforts brought on a general strategy for designing redox-switchable metal complexes that can catalyze different reactions in two oxidation states. In recent years, our contributions to this research field led to the synthesis of several multiblock copolymers prepared from biorenewable resources. This Account provides an overview of reported redox-switchable polymerization catalysts that allow for complementary reactivity in different oxidation states and highlights the potential of this strategy in preparing biodegradable materials. First, we define the field of redox-switchable catalysis and illustrate the design and significance of our ferrocene-chelating ligands, in which the oxidation state of iron in ferrocene can control the reactivity of the resulting metal complexes remotely. Next, we illustrate recent advances in the synthesis of new biodegradable copolymers including (1) how to tune the activity of the ROP catalysts by exploring various metal centers and ferrocene-based ligand combinations; (2) how to synthesize new multiblock copolymers of cyclic esters, epoxides, and carbonates by redox-switchable ROP; and (3) how to understand the mechanism of these reactions by discussing both experimental and theoretical investigations. By the application and development of redox-switchable strategies, various novel materials and reactions can be expected in the future.
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Affiliation(s)
- Junnian Wei
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | - Paula L. Diaconescu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
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80
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Mehlmann P, Dielmann F. Switching the Electron-Donating Ability of Phosphines through Proton-Responsive Imidazolin-2-ylidenamino Substituents. Chemistry 2019; 25:2352-2357. [PMID: 30506604 DOI: 10.1002/chem.201805540] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Indexed: 11/06/2022]
Abstract
Stimuli-responsive ancillary ligands are valuable tools to control the activity and selectivity of transition-metal catalysts. The synthesis and characterization of a series of metal complexes containing phosphines with proton-responsive imidazolin-2-ylidenamino substituents are reported. Determination of the ligand-donor properties revealed that protonation of each substituent increases the Tolman electronic parameter (TEP) of the phosphine by 22 cm-1 , hence allowing for switching of the electron-donor power of phosphine 2 within an unprecedented range (ΔTEP=43.4 cm-1 ).
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Affiliation(s)
- Paul Mehlmann
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 30, 48149, Münster, Germany
| | - Fabian Dielmann
- Institut für Anorganische und Analytische Chemie, Westfälische Wilhelms-Universität Münster, Corrensstrasse 30, 48149, Münster, Germany
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81
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Salen-Manganese Complexes and their Application in the Ring-Opening Polymerization of Lactide and ϵ-Caprolactone. ASIAN J ORG CHEM 2019. [DOI: 10.1002/ajoc.201800695] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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82
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Daneshmand P, Randimbiarisolo A, Schaper F. Tetradentate iminophenolate copper complexes in rac-lactide polymerization. CAN J CHEM 2019. [DOI: 10.1139/cjc-2018-0287] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Copper(II) nitrate complexes of 2-(((2-((2-aminoethyl)amino)ethyl)imino)methyl)phenol, 2-(((2-((2-aminoethyl)amino)ethyl)imino)methyl)-4,6-dichlorophenol, 2-(((2-(piperazin-1-yl)ethyl)imino)methyl)phenol and (2,4-di-tert-butyl-6-(((2-(piperazin-1-yl)ethyl)imino)methyl)phenol, as well as a copper(II) acetate complex of 2-(((2-(piperidin-1-yl)ethyl)imino)methyl)phenol, have been prepared and characterized by X-ray diffraction studies. In combination with benzyl alcohol, all complexes are active in rac-lactide polymerization at 140 °C in molten monomer to provide moderately heterotactic polylactic acid. Most complexes showed complicated reaction kinetics, indicative of two interconverting active species. Molecular weight control was poor and a strong tendency toward intramolecular transesterification led to oligomeric products. There was no indication that the basic site of the ligand is participating in the polymerization reaction by deprotonation of the alcohol nucleophile.
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Affiliation(s)
- Pargol Daneshmand
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
| | - Aurélie Randimbiarisolo
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
| | - Frank Schaper
- Centre in Green Chemistry and Catalysis, Département de chimie, Université de Montréal, 2900 Boul. E.-Montpetit, Montréal, QC H3T 1J4, Canada
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83
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Kremer AB, Mehrkhodavandi P. Dinuclear catalysts for the ring opening polymerization of lactide. Coord Chem Rev 2019. [DOI: 10.1016/j.ccr.2018.09.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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84
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85
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Cai Z, Xiao D, Do LH. Cooperative Heterobimetallic Catalysts in Coordination Insertion Polymerization. COMMENT INORG CHEM 2019. [DOI: 10.1080/02603594.2019.1570165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Zhongzheng Cai
- Department of Chemistry, University of Houston, Houston, Texas, USA
| | - Dawei Xiao
- Department of Chemistry, University of Houston, Houston, Texas, USA
| | - Loi H. Do
- Department of Chemistry, University of Houston, Houston, Texas, USA
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86
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Chen XL, Wang B, Pan L, Li YS. Homoleptic, bis-ligated magnesium complexes for ring-opening polymerization of lactide and lactones: Synthesis, structure, polymerization behavior and mechanism studies. Appl Organomet Chem 2019. [DOI: 10.1002/aoc.4770] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Xiao-Lu Chen
- Tianjin Key Lab of Composite and Functional Materials, School of Materials Science and Engineering; Tianjin University; Tianjin 300072 China
| | - Bin Wang
- Tianjin Key Lab of Composite and Functional Materials, School of Materials Science and Engineering; Tianjin University; Tianjin 300072 China
| | - Li Pan
- Tianjin Key Lab of Composite and Functional Materials, School of Materials Science and Engineering; Tianjin University; Tianjin 300072 China
| | - Yue-Sheng Li
- Tianjin Key Lab of Composite and Functional Materials, School of Materials Science and Engineering; Tianjin University; Tianjin 300072 China
- Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300072 China
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87
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Cui Y, Jiang J, Mao X, Wu J. Mononuclear Salen-Sodium Ion Pairs as Catalysts for Isoselective Polymerization of rac-Lactide. Inorg Chem 2019; 58:218-227. [PMID: 30543276 DOI: 10.1021/acs.inorgchem.8b02290] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
A series of mononuclear salen-sodium anions, as the first examples, were synthesized with tetra-alkyl ammonium as a counterpart cation. These complexes are efficient catalysts for the isoselective ring-opening polymerization of rac-lactide; the molecular weights of polymers are under control and molecular weight distributions are narrow when five equivalents of BnOH is used as an initiator. The best isoselectivity value of Pm = 0.82 was achieved at -70 °C. The experimental results together with a density functional theory calculation show that a ligand-assisted activated monomer mechanism is more reasonable than an activated monomer mechanism for this system.
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Affiliation(s)
- Yaqin Cui
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Jinxing Jiang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Xiaoyang Mao
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , People's Republic of China
| | - Jincai Wu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province , Lanzhou University , Lanzhou 730000 , People's Republic of China
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88
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Sokolovicz YCA, Schrekker CML, Hild F, de Oliveira Bodo L, Couto JL, Klitzke JS, Maraschin T, de Souza Basso NR, dos Santos JHZ, Dagorne S, Schrekker HS. Organometal-catalyzed synthesis of high molecular weight poly-(l-lactic acid) with a covalently attached imidazolium salt: performance-enhanced reduced graphene oxide–PLLA biomaterials. NEW J CHEM 2019. [DOI: 10.1039/c9nj03978c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Herein, we report on the synthesis of imidazolium salt end-functionalized PLLA (PLLA-IS) and its application in the preparation of reduced graphene oxide–PLLA composites.
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Affiliation(s)
| | | | - Frédéric Hild
- Institute of Chemistry
- Université de Strasbourg
- CNRS
- Strasbourg
- France
| | | | | | | | - Thuany Maraschin
- School of Technology
- Pontifica Universidade Católica do Rio Grande do Sul
- Porto Alegre
- Brazil
| | | | | | - Samuel Dagorne
- Institute of Chemistry
- Université de Strasbourg
- CNRS
- Strasbourg
- France
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89
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Dai R, Diaconescu PL. Investigation of a zirconium compound for redox switchable ring opening polymerization. Dalton Trans 2019; 48:2996-3002. [DOI: 10.1039/c9dt00212j] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Redox switchable catalysis with a ferrocene Schiff base zirconium complex allowed the synthesis of diblock and triblock copolymers.
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Affiliation(s)
- Ruxi Dai
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
| | - Paula L. Diaconescu
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
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90
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Gao J, Zhu D, Zhang W, Solan GA, Ma Y, Sun WH. Recent progress in the application of group 1, 2 & 13 metal complexes as catalysts for the ring opening polymerization of cyclic esters. Inorg Chem Front 2019. [DOI: 10.1039/c9qi00855a] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This review focuses on recent developments concerned with the use of well-defined main group complexes as (pre-)catalysts for the ROP of cyclic esters to give aliphatic polyesters; factors influencing catalytic activity, selectivity and polymer properties are all discussed.
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Affiliation(s)
- Jiahao Gao
- 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
| | - Dongzhi Zhu
- 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
| | - Wenjuan Zhang
- 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
| | - 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
| | - 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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91
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Pan Y, Li W, Wei NN, So YM, Lai X, Li Y, Jiang K, He G. Highly active rare-earth metal catalysts for heteroselective ring-opening polymerization of racemic lactide. Dalton Trans 2019; 48:9079-9088. [PMID: 31017172 DOI: 10.1039/c9dt00541b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Rare-earth metal complexes usually exhibit high activities in the ring-opening polymerization (ROP) of lactide, yet only a few scandium complexes have shown satisfactory activity. Herein, we report the synthesis of a series of chiral anilido-oxazoline-supported scandium and yttrium complexes that exhibit high activity in the ROP of racemic lactide (rac-LA). Complexes La-f-Ln(CH2SiMe3)2THF (La-f = 2-(2,6-R2PhN)-phenyl-4-(S)-R'-oxazoline; for 1a-f: L = La-f, Ln = Sc; for 2a-d: L = La-d, Ln = Y) were synthesized via the convenient one-pot reaction of Ln(CH2SiMe3)3(THF)2 (Ln = Sc, Y) with the corresponding proligands. The crystal structures of 1a, 1d, 1e, and 1f were isostructural, adopting a distorted trigonal bipyramidal configuration. Sc complexes 1 showed outstanding activity in the ROP of rac-LA with heteroselectivity. TOFs of up to 720 h-1 and 2910 h-1 were obtained in THF at room temperature and toluene at 60 °C, respectively. To our knowledge, these are the highest activities reported for Sc systems. Y complexes 2 showed higher activity and heteroselectivity than the Sc complexes, with TOFs of up to 1176 h-1 in THF at room temperature. Compared with the ortho-substituent on the anilido moiety, the bulky substituent at the chiral center of the oxazoline ring had a greater effect on controlling the heteroselectivity.
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Affiliation(s)
- Yu Pan
- State Key Laboratory of Fine Chemicals, School of Petroleum and Chemical Engineering, Dalian University of Technology, Panjin 124221, China.
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92
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Maji B, Choudhury J. Switchable hydrogenation with a betaine-derived bifunctional Ir–NHC catalyst. Chem Commun (Camb) 2019; 55:4574-4577. [DOI: 10.1039/c9cc00972h] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A bifunctional iridium catalyst based on the ‘uracil–abnormal NHC’ hybrid ligand platform was developed for switchable hydrogenation of quinoxalines.
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Affiliation(s)
- Babulal Maji
- Organometallics & Smart Materials Laboratory
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER) Bhopal
- Bhopal 462 066
- India
| | - Joyanta Choudhury
- Organometallics & Smart Materials Laboratory
- Department of Chemistry
- Indian Institute of Science Education and Research (IISER) Bhopal
- Bhopal 462 066
- India
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93
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Xu X, Luo G, Mehmood A, Zhao Y, Zhou G, Hou Z, Luo Y. Theoretical Mechanistic Studies on Redox-Switchable Polymerization of Trimethylene Carbonate Catalyzed by an Indium Complex Bearing a Ferrocene-Based Ligand. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00599] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Xiaowei Xu
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Gen Luo
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Andleeb Mehmood
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Yanan Zhao
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Guangli Zhou
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
| | - Zhaomin Hou
- Organometallic Chemistry Laboratory, RIKEN Cluster for Pioneering Research, and Advanced Catalysis Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yi Luo
- State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China
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94
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Stößer T, Mulryan D, Williams CK. Switch Catalysis To Deliver Multi-Block Polyesters from Mixtures of Propene Oxide, Lactide, and Phthalic Anhydride. Angew Chem Int Ed Engl 2018; 57:16893-16897. [PMID: 30370965 PMCID: PMC6391959 DOI: 10.1002/anie.201810245] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/09/2018] [Indexed: 12/31/2022]
Abstract
Switchable polymerisation catalysis enables block polymer sequence selectivity from monomer mixtures, resulting in the formation of multiblock polyesters. The aluminium salphen catalyst switches between two different polymerisation mechanisms and selectively enchains mixtures of commercially available monomers: lactide, phthalic anhydride, and propene oxide. Sequential monomer mixture additions yield multi-block polyesters featuring 3, 7, 11, 15, 19, 23, and 27 blocks. The unparalleled catalytic selectivity can be used to access completely new multi-block polyesters relevant for future applications.
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Affiliation(s)
- Tim Stößer
- Department of ChemistryOxford UniversityChemical Research Laboratory12 Mansfield RoadOxfordOX1 3TAUK
| | - Daniel Mulryan
- Department of ChemistryOxford UniversityChemical Research Laboratory12 Mansfield RoadOxfordOX1 3TAUK
| | - Charlotte K. Williams
- Department of ChemistryOxford UniversityChemical Research Laboratory12 Mansfield RoadOxfordOX1 3TAUK
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95
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Stößer T, Mulryan D, Williams CK. Schaltbare Katalyse zur Herstellung von Multiblock‐Polyestern aus einer Mischung von Propylenoxid, Lactid und Phthalsäureanhydrid. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201810245] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Tim Stößer
- Department of ChemistryOxford UniversityChemical Research Laboratory 12 Mansfield Road Oxford OX1 3TA Großbritannien
| | - Daniel Mulryan
- Department of ChemistryOxford UniversityChemical Research Laboratory 12 Mansfield Road Oxford OX1 3TA Großbritannien
| | - Charlotte K. Williams
- Department of ChemistryOxford UniversityChemical Research Laboratory 12 Mansfield Road Oxford OX1 3TA Großbritannien
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96
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Sarmah K, Mukhopadhyay S, Maji TK, Pratihar S. Switchable Bifunctional Bistate Reusable ZnO–Cu for Selective Oxidation and Reduction Reaction. ACS Catal 2018. [DOI: 10.1021/acscatal.8b03785] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Kasturi Sarmah
- Department of Chemical Sciences, Tezpur University, Napaam, Assam−784028, India
| | | | - Tarun K. Maji
- Department of Chemical Sciences, Tezpur University, Napaam, Assam−784028, India
| | - Sanjay Pratihar
- Department of Chemical Sciences, Tezpur University, Napaam, Assam−784028, India
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97
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98
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Dai R, Lai A, Alexandrova AN, Diaconescu PL. Geometry Change in a Series of Zirconium Compounds during Lactide Ring-Opening Polymerization. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00620] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Ruxi Dai
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Amy Lai
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Anastassia N. Alexandrova
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Paula L. Diaconescu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
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99
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Garcés A, Sánchez-Barba LF, Fernández-Baeza J, Otero A, Fernández I, Lara-Sánchez A, Rodríguez AM. Organo-Aluminum and Zinc Acetamidinates: Preparation, Coordination Ability, and Ring-Opening Polymerization Processes of Cyclic Esters. Inorg Chem 2018; 57:12132-12142. [PMID: 30212185 DOI: 10.1021/acs.inorgchem.8b01723] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The reaction of the highly sterically demanding NNN'-heteroscorpionate protioligands pbptamd-H, tbptamd-H, and phbptamd-H (a) and the low sterically hindered analogs pbpamd-H, tbpamd-H, and phbpamd-H (b), with 1 equiv of AlR3 (R = Me, Et) proceed in high yields to give two families of complexes: the mononuclear dialkyl aluminum bidentate-acetamidinates [AlR2(κ2- N' N')] (κ2- N' N' = pbptamd, R = Me 1, Et 2; tbptamd, R = Me 3, Et 4; phbptamd, R = Me 5, Et 6) and the monodentate-acetamidinates [AlR2(κ2- NN')] (κ2- NN' = tbpamd, R = Me 7; phbpamd, R = Me 8, Et 9). In complexes 7-9, the presence of two possible CH-NH tautomers as low extended π-N-C-N'(sp2)-Al and high extended π-HN-C2-N'(sp2)-Al complexes, respectively, could be identified. Moreover, the reaction of aluminum dimethyls 7 and 8 with ZnMe2 afforded the isolation of the more stable scorpionate zinc monoalkyls [Zn(Me)(κ3- NNN')] ( NNN' = tbpamd 10 and phbpamd 11), through a very unusual ligand exchange process, involving a zinc-to-aluminum transmetalation of an alkyl group. The X-ray crystal structures of 1, 3, 7, and 8, as well as that of 11, confirmed unambiguously the different κ2-arrangements proposed for bi- or monodentate acetamidinate dialkyls 1-6 and 7-9, respectively, the presence of NH tautomer in 7 and 8, and a κ3- NNN' coordination in monoalkyl 11. Density functional theory calculations were used to explore the three different favored κ2-arrangements found in acetamidinate aluminum dialkyls 1-9, the relative stability of both CH-NH tautomers, and the ligand transfer reaction leading to the formation of κ3- NNN' zinc monoalkyls 10 and 11. Interestingly, dialkyls 1, 5, 7, and 8 can act as highly efficient single-component living initiators for the ring-opening polymerization of ε-caprolactone and rac-lactide in mild conditions after hours. These initiators efficiently mediated the immortal polymerization in the presence of excess of benzyl alcohol (up to 20 equiv), as evidenced by the narrow dispersity values and the good agreement between the experimental Mn values and monomer/benzyl alcohol ratios. In addition, the most sterically hindered initiator, 5, exhibits enhanced levels of heteroselectivity on the produced PLAs, reaching Ps values up to 0.70.
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Affiliation(s)
- Andrés Garcés
- Departamento de Biología y Geología, Física y Química Inorgánica , Universidad Rey Juan Carlos, Móstoles , 28933 Madrid , Spain
| | - Luis F Sánchez-Barba
- Departamento de Biología y Geología, Física y Química Inorgánica , Universidad Rey Juan Carlos, Móstoles , 28933 Madrid , Spain
| | - Juan Fernández-Baeza
- Universidad de Castilla-La Mancha , Departamento de Química Inorgánica, Orgánica y Bioquímica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), Campus Universitario , 13071 Ciudad Real , Spain
| | - Antonio Otero
- Universidad de Castilla-La Mancha , Departamento de Química Inorgánica, Orgánica y Bioquímica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), Campus Universitario , 13071 Ciudad Real , Spain
| | - Israel Fernández
- Departamento de Química Orgánica I, Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas , Universidad Complutense de Madrid , 28040 Madrid , Spain
| | - Agustín Lara-Sánchez
- Universidad de Castilla-La Mancha , Departamento de Química Inorgánica, Orgánica y Bioquímica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), Campus Universitario , 13071 Ciudad Real , Spain
| | - Ana M Rodríguez
- Universidad de Castilla-La Mancha , Departamento de Química Inorgánica, Orgánica y Bioquímica, Centro de Innovación en Química Avanzada (ORFEO-CINQA), Campus Universitario , 13071 Ciudad Real , Spain
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100
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Kernbichl S, Reiter M, Bucalon DH, Altmann PJ, Kronast A, Rieger B. Synthesis of Lewis Acidic, Aromatic Aminotroponiminate Zinc Complexes for the Ring-Opening Polymerization of Cyclic Esters. Inorg Chem 2018; 57:9931-9940. [PMID: 30074390 DOI: 10.1021/acs.inorgchem.8b01060] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Three novel aminotroponiminate (ATI) zinc complexes I-III (I = [(Ph2)ATI]Zn-N(SiMe3)2, II = [(C6H3-2,6-C2H5/Ph)ATI]Zn-N(SiMe3)2, and III = [(C6H3-2,6-CH(CH3)2/Ph)ATI]Zn-N(SiMe3)2) were synthesized and tested in the ring-opening polymerization of the lactones β- rac-butyrolactone (BBL) and rac-lactide (LA). The ligands, with two of them literature unknown, were readily obtained via a three-step synthesis from tropolone. Forming a five-membered metallacycle with zinc, the complexes were further structurally examined via single-crystal X-ray analysis and compared with that of the established, 6-ringed β-diiminate (BDI) complex IV ([CH(CMeNPh)2]Zn-N(SiMe3)2). The influence of the varying metallacycle ring size on the polymerization was evaluated. In situ IR measurements indicate a higher catalytic activity of the novel ATI complexes I-III for BBL compared with the BDI system IV. The activity and degree of control were further improved by an in situ generated alkoxy initiating group generated after the addition of 2-propanol. An enhanced initiator efficiency allowed the synthesis of polymers with controlled molecular weights and narrow polydispersities. Furthermore, II and III exhibited a high activity in the ring-opening polymerization of rac-LA. Hereby, reaction time and initiator efficiency could also be optimized at a higher temperature or by the addition of 2-propanol.
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Affiliation(s)
- Sebastian Kernbichl
- Wacker-Lehrstuhl für Makromolekulare Chemie, Catalysis Research Center , Technische Universität München , Lichtenbergstraße 4 , 85748 Garching bei München , Germany
| | - Marina Reiter
- Wacker-Lehrstuhl für Makromolekulare Chemie, Catalysis Research Center , Technische Universität München , Lichtenbergstraße 4 , 85748 Garching bei München , Germany
| | - Daniel H Bucalon
- Wacker-Lehrstuhl für Makromolekulare Chemie, Catalysis Research Center , Technische Universität München , Lichtenbergstraße 4 , 85748 Garching bei München , Germany.,Departamento de Química , Universitade Federal de São Carlos , Via Washington Luiz, km 235 , 13565-905 São Carlos , SP , Brazil
| | - Philipp J Altmann
- Catalysis Research Center , Technische Universität München , Ernst-Otto-Fischer Straße 1 , 85748 Garching bei München , Germany
| | - Alexander Kronast
- Wacker-Lehrstuhl für Makromolekulare Chemie, Catalysis Research Center , Technische Universität München , Lichtenbergstraße 4 , 85748 Garching bei München , Germany
| | - Bernhard Rieger
- Wacker-Lehrstuhl für Makromolekulare Chemie, Catalysis Research Center , Technische Universität München , Lichtenbergstraße 4 , 85748 Garching bei München , Germany
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