1
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Rentero C, Damián J, Medel A, Fernández-Millán M, Rusconi Y, Talarico G, Cuenca T, Sessini V, Mosquera MEG. Ring-Opening Polymerization of L-Lactide Catalyzed by Potassium-Based Complexes: Mechanistic Studies. Polymers (Basel) 2022; 14:polym14152982. [PMID: 35893946 PMCID: PMC9329769 DOI: 10.3390/polym14152982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 07/18/2022] [Accepted: 07/20/2022] [Indexed: 02/05/2023] Open
Abstract
Two non-toxic potassium compounds, 1 and 2, with a commercial oximate ligand have been prepared and fully spectroscopically characterized. Their activity as catalysts for the ring-opening polymerization (ROP) process of LLA has been studied, showing that they are extremely active and able to polymerize the monomer in a few minutes. For derivative 2, the presence of a crown ether in the potassium coordination sphere affects the nuclearity of the compound and consequently its solubility, with both aspects having an influence in the polymerization process. Detailed studies of the polymerization mechanism have been performed, and an unusual anionic mechanism was observed in absence of a co-initiator. Indeed, the monomer deprotonation generates a lactide enolate, which initiates the polymerization propagation. On the contrary, when a 1:1 ratio of cat:BnOH is used, a mixture of mechanisms is observed, the anionic mechanism and the activated monomer one, while from a cat:BnOH ratio of 1:2 and over, only the activated monomer mechanism is observed.
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Affiliation(s)
- Christian Rentero
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
| | - Jesús Damián
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
| | - Asier Medel
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
| | - María Fernández-Millán
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
| | - Yolanda Rusconi
- Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, Via Cintia, 80124 Napoli, Italy; (Y.R.); (G.T.)
| | - Giovanni Talarico
- Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, Via Cintia, 80124 Napoli, Italy; (Y.R.); (G.T.)
| | - Tomás Cuenca
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
| | - Valentina Sessini
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
- Correspondence: (V.S.); (M.E.G.M.)
| | - Marta E. G. Mosquera
- Department of Organic and Inorganic Chemistry, Institute of Chemical Research “Andrés M. del Río” (IQAR), Universidad de Alcalá, Campus Universitario, 28871 Madrid, Spain; (C.R.); (J.D.); (A.M.); (M.F.-M.); (T.C.)
- Correspondence: (V.S.); (M.E.G.M.)
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2
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Dong X, Robinson JR. The versatile roles of neutral donor ligands in tuning catalyst performance for the ring-opening polymerization of cyclic esters. NEW J CHEM 2022. [DOI: 10.1039/d1nj02694a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of neutral donor ligands is an effective strategy to modify catalyst structure and performance in the synthesis of sustainable polymers through the ring-opening polymerization (ROP) of cyclic esters.
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Affiliation(s)
- Xiang Dong
- Department of Chemistry, Brown University, 324 Brook St. Providence, RI 02912, USA
| | - Jerome R. Robinson
- Department of Chemistry, Brown University, 324 Brook St. Providence, RI 02912, USA
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3
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Ring-opening polymerization of L-lactide by using sodium complexes bearing amide as catalysts in high polar solvent. Polym Bull (Berl) 2021. [DOI: 10.1007/s00289-020-03240-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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4
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Wang X, Wang X, Zhen N, Gu J, Zhang H, Dong B, Wang F, Liu H. Sodium complexes bearing cavity-like conformations: a highly active and well-controlled catalytic system for macrolactone homo- and copolymerization. Polym Chem 2021. [DOI: 10.1039/d0py01580f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sodium complexes displaying cavity-like conformations and, therefore, suppressed transesterification during the ring-opening polymerization of pentadecalactone are disclosed herein.
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Affiliation(s)
- Xinya Wang
- College of Food Science and Engineering
- National Engineering Laboratory for Wheat and Corn Deep Processing
- Jilin Agricultural University
- Changchun 130118
- PR China
| | - Xiaohua Wang
- Key Laboratory of Rubber-Plastics
- Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plastics
- Qingdao University of Science & Technology
- Qingdao
- China
| | - Nuo Zhen
- College of Food Science and Engineering
- National Engineering Laboratory for Wheat and Corn Deep Processing
- Jilin Agricultural University
- Changchun 130118
- PR China
| | - Jin Gu
- College of Food Science and Engineering
- National Engineering Laboratory for Wheat and Corn Deep Processing
- Jilin Agricultural University
- Changchun 130118
- PR China
| | - Hao Zhang
- College of Food Science and Engineering
- National Engineering Laboratory for Wheat and Corn Deep Processing
- Jilin Agricultural University
- Changchun 130118
- PR China
| | - Bo Dong
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun 130022
- P.R. China
| | - Feng Wang
- Key Laboratory of Rubber-Plastics
- Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plastics
- Qingdao University of Science & Technology
- Qingdao
- China
| | - Heng Liu
- Key Laboratory of Rubber-Plastics
- Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plastics
- Qingdao University of Science & Technology
- Qingdao
- China
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5
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Hanft A, Jürgensen M, Wolz L, Radacki K, Lichtenberg C. Salicylaldimines: Formation via Ring Contraction and Synthesis of Mono- and Heterobimetallic Alkali Metal Heterocubanes. Inorg Chem 2020; 59:17678-17688. [PMID: 33226783 DOI: 10.1021/acs.inorgchem.0c02920] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The formation of salicylaldimine derivatives via ring contraction as byproducts in 2-aminotropone syntheses has been investigated. Salicylaldiminate (SAI) complexes of the alkali metals Li-K have been synthesized and transformed into heterobimetallic complexes. Important findings include an unusual double heterocubane structure of the homometallic sodium SAI, an unprecedented ligand-induced E/Z isomerization of the aldimine functional group in the homometallic potassium SAI, and the first example of a structurally authenticated mixed-metal SAI based on s-block central atoms. Rapid equilibria have been shown to play a crucial role in the solution phase chemistry of mixed-metal SAIs. Analytical techniques applied in this work include (heteronuclear) NMR spectroscopy, VT- and DOSY NMR spectroscopy, high-resolution mass spectrometry, single-crystal X-ray diffraction analysis, and DFT calculations.
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Affiliation(s)
- Anna Hanft
- Department of Inorganic Chemistry, Julius-Maximilians Universität, Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Malte Jürgensen
- Department of Inorganic Chemistry, Julius-Maximilians Universität, Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Laura Wolz
- Department of Inorganic Chemistry, Julius-Maximilians Universität, Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Krzysztof Radacki
- Department of Inorganic Chemistry, Julius-Maximilians Universität, Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Crispin Lichtenberg
- Department of Inorganic Chemistry, Julius-Maximilians Universität, Würzburg, Am Hubland, 97074 Würzburg, Germany
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6
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Wan Y, Bai Y, Xu H, He J, Zhang Y. Highly Isoselective Ring-Opening Polymerization of rac-Lactide Using Chiral Binuclear Aluminum Catalyst. Macromol Rapid Commun 2020; 42:e2000491. [PMID: 33200483 DOI: 10.1002/marc.202000491] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 10/04/2020] [Indexed: 12/26/2022]
Abstract
The microstructure can significantly affect the physical and mechanical properties of polymers. Five chiral binuclear aluminum methyl complexes (rac1 to rac5) are synthesized by using chiral binaphthalene diamine ligand and characterized by both 1 H and 13 C NMR spectroscopy. The crystal structures of rac3 and rac5 are also identified by single crystal X-ray diffraction. In the presence of i PrOH initiator, these aluminum complexes catalyze the ring-opening polymerization (ROP) of rac-lactide (rac-LA) in a controlled manner and produce polymers with high to excellent isoselectivity (Pm up to 0.93). Even with a catalyst loading as low as 0.1%, polylactide with a Pm of 0.83 can still be obtained. Kinetic studies reveal the first-order dependence on monomer concentration whereas kinetic resolution polymerization provides the evidence to support that these binuclear aluminum catalysts catalyzed ROP of rac-LA adopts enantiomorphic site control mechanism. Furthermore, this strategy can also be applied to the ROP of both ε-caprolactone and δ-valeroactone.
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Affiliation(s)
- Yi Wan
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China
| | - Yun Bai
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China
| | - Hai Xu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China
| | - Jianghua He
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China
| | - Yuetao Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China
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7
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Marszałek-Harych A, Trybuła D, Jędrzkiewicz D, Ejfler J. Scrabbling around in Synthetic Nuances Managing Sodium Compounds: Bisphenol/Bisnaphthol Synthesis by Hydroxyl Group Masking. Inorg Chem 2020; 59:6895-6904. [PMID: 32353236 PMCID: PMC7467675 DOI: 10.1021/acs.inorgchem.0c00310] [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] [Indexed: 11/29/2022]
Abstract
![]()
A unique
method of bisphenol/bisnaphthol synthesis is being proposed,
serendipitously discovered in the course of the careful analysis of
an aminophenol methylation reaction. The insightful exploration of
the synthesis of N- or O-methylated species, originating from functionalized
phenols obtained by a conventional strategy, provided the opportunity
to discover an unexpected reaction pathway yielding various bisphenols.
Sodium complexes were found to be crucial intermediates in the synthetic
scenario. Their formation, which is usually an imperceptive step,
was substantial for the productive outcome of functional group protection.
Thorough exploration revealed an essential structural motif of aminophenolate,
necessary for the successful outcome of the reaction, and also enabled
establishing the limitations of the new method. The work demonstrated
that a slight change in the perspective and close inspection of the
synthetic nuances can answer the important question concerning what
a specific target-oriented synthesis strategy is lacking. The protection of the hydroxyl group of aminophenols with
use of MeI—a general and, in many cases, excellent methylation
reagent—was investigated. In-depth understanding of the mechanistic
aspects of methyl protective group incorporation provided a practical
guide for its application in organic synthesis, but it also opened
a new route for the synthesis of an original group of bisphenols.
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Affiliation(s)
| | - Danuta Trybuła
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50-383 Wrocław, Poland
| | - Dawid Jędrzkiewicz
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50-383 Wrocław, Poland
| | - Jolanta Ejfler
- Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie, 50-383 Wrocław, Poland
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8
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Yu X, Zhang C, Wang Z. Controlled Polymerization of ϵ‐Caprolactone using Aluminum and Zinc Complexes with Iminophosphorane Ligands. ChemistrySelect 2020. [DOI: 10.1002/slct.201904185] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xiaofeng Yu
- School of Materials and Chemical EngineeringBengbu University Bengbu, Anhui 233030 P. R. China
| | - Cheng Zhang
- School of Engineering and TechnologyBeijing Normal University Zhuhai Campus, Zhuhai Guangdong 510000 P. R. China
| | - Zhongxia Wang
- Department of ChemistryUniversity of Science and Technology of China, Hefei Anhui 230026 P. R. of China
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9
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García-Valle FM, Muñoz MT, Cuenca T, Milione S, Mosquera ME, Cano J. Fluorinated alkali metal catalysts for the Ring-Opening Polymerization (ROP) of rac-lactide. Effect of the M···F interactions in the polymerization control. J Organomet Chem 2019. [DOI: 10.1016/j.jorganchem.2019.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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10
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Stewart JA, McKeown P, Driscoll OJ, Mahon MF, Ward BD, Jones MD. Tuning the Thiolen: Al(III) and Fe(III) Thiolen Complexes for the Isoselective ROP of rac-Lactide. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b01205] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Jack A. Stewart
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Paul McKeown
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Oliver J. Driscoll
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Mary F. Mahon
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
| | - Benjamin D. Ward
- Department of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, U.K
| | - Matthew D. Jones
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K
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11
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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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12
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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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13
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Harinath A, Bhattacharjee J, Sarkar A, Panda TK. Alkali metal complex-mediated ring-opening polymerization of rac-LA, ε-caprolactone, and δ-valerolactone. NEW J CHEM 2019. [DOI: 10.1039/c9nj01130g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Catalytic ring opening polymerization (ROP) of rac-lactide, ε-caprolactone, and δ-valerolactone using alkali metal (Li, Na, K) complexes as competent catalysts are reported.
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Affiliation(s)
- Adimulam Harinath
- Department of Chemistry
- Indian Institute of Technology Hyderabad Kandi – 502 285
- Sangareddy
- India
| | - Jayeeta Bhattacharjee
- Department of Chemistry
- Indian Institute of Technology Hyderabad Kandi – 502 285
- Sangareddy
- India
| | - Alok Sarkar
- Momentive Performance Materials Pvt. Ltd
- Bangalore – 560 100
- India
| | - Tarun K. Panda
- Department of Chemistry
- Indian Institute of Technology Hyderabad Kandi – 502 285
- Sangareddy
- India
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14
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Chen C, Jiang J, Mao X, Cong Y, Cui Y, Pan X, Wu J. Isoselective Polymerization of rac-Lactide Catalyzed by Ion-Paired Potassium Amidinate Complexes. Inorg Chem 2018; 57:3158-3168. [PMID: 29494145 DOI: 10.1021/acs.inorgchem.7b03184] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Three potassium crown ether complexes supported with bulky amidinate ligands were synthesized for the ring-opening polymerization (ROP) of rac-lactide. The side polymerization reaction initiated directly by ligand anion was suppressed well in the presence of alcohol as our design, and the synthesis of linear polylactide with a molecular weight as high as 117.7 kg/mol was successful together with an isoselectivity value of Pm = 0.88 at -70 °C. In this system, lactide can be deprotonated by amidinate anion to give lactide enolate, which can initiate the ROP of lactide as a side reaction in the absence of alcohol; however, this side reaction can also be suppressed well in the presence of alcohol by a decrease in temperature. An interesting anti-Arrhenius-like behavior in the polymerization was discovered, which can be attributed to the fact that the active catalyst can be converted to a less active lactide enolate potassium complex at a high temperature.
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Affiliation(s)
- Changjuan Chen
- 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.,College of Chemistry and Pharmaceutical Engineering , Huanghuai University , Zhumadian 463000 , 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
| | - Yong Cong
- 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
| | - 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
| | - Xiaobo Pan
- 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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15
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