1
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Kang C, Jung K, Ahn S, Choi TL. Controlled Cyclopolymerization of 1,5-Hexadiynes to Give Narrow Band Gap Conjugated Polyacetylenes Containing Highly Strained Cyclobutenes. J Am Chem Soc 2020; 142:17140-17146. [PMID: 32915557 DOI: 10.1021/jacs.0c07666] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
For decades, cyclopolymerization of α,ω-diyne derivatives has been an effective method to synthesize various soluble polyacetylenes containing five- to seven-membered rings in the backbone. However, cyclopolymerization to form four-membered carbocycles was considered impossible due to their exceptionally high ring strain (∼30 kcal/mol). Herein, we demonstrate the successful cyclopolymerization of rationally designed 1,5-hexadiyne derivatives to afford various polyacetylenes containing highly strained cyclobutenes in each repeat unit. After screening, Ru catalysts containing bulky diisopropylphenyl groups promoted challenging four-membered ring cyclization efficiently from various monomers, enabling the synthesis of high molecular weight (up to 40 kDa) polyacetylenes in a controlled manner. Furthermore, living polymerization allowed for block copolymer synthesis by combining with ring-opening metathesis polymerization as well as block copolymerization of two different 1,5-hexadiyne monomers to give a fully conjugated polyacetylene. These new polymers unexpectedly showed much narrower band gaps than conventional substituted polyacetylenes by >0.2 eV. Interestingly, computational studies showed much smaller bond length alternation in the conjugated backbone containing cyclobutenes, resulting in highly delocalized π electrons along the polymer chain and lower band gaps.
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Affiliation(s)
- Cheol Kang
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Kijung Jung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sojeong Ahn
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
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2
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Jung K, Ahmed TS, Lee J, Sung JC, Keum H, Grubbs RH, Choi TL. Living β-selective cyclopolymerization using Ru dithiolate catalysts. Chem Sci 2019; 10:8955-8963. [PMID: 31762976 PMCID: PMC6855257 DOI: 10.1039/c9sc01326a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 07/22/2019] [Indexed: 11/21/2022] Open
Abstract
Cyclopolymerization (CP) of 1,6-heptadiyne derivatives is a powerful method for synthesizing conjugated polyenes containing five- or six-membered rings via α- or β-addition, respectively. Fifteen years of studies on CP have revealed that user-friendly Ru-based catalysts promoted only α-addition; however, we recently achieved β-selective regiocontrol to produce polyenes containing six-membered-rings, using a dithiolate-chelated Ru-based catalyst. Unfortunately, slow initiation and relatively low catalyst stability inevitably led to uncontrolled polymerization. Nevertheless, this investigation gave us some clues to how successful living polymerization could be achieved. Herein, we report living β-selective CP by rational engineering of the steric factor on monomer or catalyst structures. As a result, the molecular weight of the conjugated polymers from various monomers could be controlled with narrow dispersities, according to the catalyst loading. A mechanistic investigation by in situ kinetic studies using 1H NMR spectroscopy revealed that with appropriate pyridine additives, imposing a steric demand on either the monomer or the catalyst significantly improved the stability of the propagating carbene as well as the relative rates of initiation over propagation, thereby achieving living polymerization. Furthermore, we successfully prepared diblock and even triblock copolymers with a broad monomer scope.
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Affiliation(s)
- Kijung Jung
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea .
| | - Tonia S Ahmed
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis , Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , USA
| | - Jaeho Lee
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea .
| | - Jong-Chan Sung
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea .
| | - Hyeyun Keum
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea .
| | - Robert H Grubbs
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis , Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , USA
| | - Tae-Lim Choi
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea .
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3
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Peterson GI, Yang S, Choi TL. Synthesis of Functional Polyacetylenes via Cyclopolymerization of Diyne Monomers with Grubbs-type Catalysts. Acc Chem Res 2019; 52:994-1005. [PMID: 30689346 DOI: 10.1021/acs.accounts.8b00594] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Metathesis cyclopolymerization (CP) of α,ω-diynes is a powerful method to prepare functional polyacetylenes (PAs). PAs have long been studied due to their interesting electrical, optical, photonic, and magnetic properties which make them candidates for use in various advanced applications. Grubbs catalysts are widely used throughout synthetic chemistry, largely due to their accessibility, high reactivity, and tolerance to air, moisture, and many functional groups. Prior to our entrance into this field, only a few examples of CP using modified Grubbs catalysts existed. Inspired by these works, we saw an opportunity to expand the accessibility and utility of Grubbs-catalyzed CPs. We began by exploring CP with popular and commercially available Grubbs catalysts. We found Grubbs third-generation catalyst (G3) to be an excellent catalyst when we used strategies to stabilize the propagating Ru carbene, such as decreasing the polymerization temperature or using weakly coordinating solvent or ligands. Controlled living polymerizations were demonstrated using various 1,6-heptadiyne monomers and yielded polymers with exclusively 5-membered rings (via α-addition) in the polymer backbone. The strategy of stabilizing the Ru carbene was also critical to successful CP with Hoveyda-Grubbs second-generation (HG2) and Grubbs first-generation (G1) catalysts. We found that decomposed Ru species were catalyzing side reactions which could be completely shut down by decreasing the reaction temperature or using weakly coordinating ligands. While HG2 generally led to uncontrolled polymerizations, we found it to be an effective catalyst for monomers with very large side chains. G1 displayed broader functional group tolerance and thus broader monomer scope than G3. We next looked at our ability to change the regioselectivity of the polymerization by using Z-selective catalysts which favor β-addition and the formation of 6-membered rings in the polymer backbone. While modest β-selectivity could be obtained using Grubbs Z-selective catalyst at low temperatures, we found that by using one of Hoveyda and co-workers' catalysts with decreased carbene electrophilicity, we could achieve exclusive formation of 6-membered rings. We also pursued alternative routes to achieve 6+-membered rings in the polymer backbone by using diyne monomers with increased distance between alkynes. We found that optimizing the monomer structure for CP was an effective strategy to achieve controlled polymerizations. By using bulky substituents (maximizing the Thorpe-Ingold effect) and/or using heteroatoms (shorter bonds) to bring the alkynes closer together, controlled living CP could be achieved with various 1,7-octadiyne and 1,8-nonadiyne monomers. Finally, we took advantage of several inherent properties of controlled CP techniques to prepare polymers with advanced architectures and nanostructures. For instance, the living nature of the polymerization enabled production of block copolymers, the tolerance of very large substituents enabled production of dendronized and brush polymers, and the insolubility or crystallinity of some monomers was utilized for the spontaneous self-assembly of polymers into various one- and two-dimensional nanostructures. Overall, the strategies of stabilizing the propagating Ru carbene, modulating the selectivity and reactivity of the Ru carbene, and enhancing the inherent reactivity of monomers were key to improving the utility and performance of CP with Grubbs-type catalysts. The insight provided by these studies will be important for future developments of CP and other metathesis polymerizations utilizing ring-closing steps.
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Affiliation(s)
- Gregory I. Peterson
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Sanghee Yang
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
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4
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Kang C, Kwon S, Sung JC, Kim J, Baik MH, Choi TL. Living Metathesis and Metallotropy Polymerization Gives Conjugated Polyenynes from Multialkynes: How to Design Sequence-Specific Cascades for Polymers. J Am Chem Soc 2018; 140:16320-16329. [PMID: 30427194 DOI: 10.1021/jacs.8b10269] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
On the basis of a combined experimental and computational study, a novel method for preparing fully conjugated polyenynes via cascade metathesis and metallotropy (M&M) polymerization of various multialkynes is developed. DFT calculations elucidate the detailed mechanism of the metallotropic 1,3-shift, which is a key process of M&M polymerization. An α,β-(C,C,C)-agostic interaction stabilizing the metallacyclobutadiene transition state is found to be critically important for the successful polymerization with excellent specificity. The polymerization efficiency displayed by the tetrayne monomer is controlled by the steric demands of its substituents, and more complex hexayne monomers can be successfully polymerized to give access to highly conjugated polyenynes via a series of intramolecular metathesis and metallotropic shift cascade reactions. Furthermore, living polymerization led to the synthesis of block copolymers consisting of fully conjugated polyenyne backbones. The implementation of pentayne monomers provides polyenynes with successive C-C triple bonds via consecutive metallotropic 1,3-shift. In short, the design of multialkynes enables the preparation of diverse conjugated polyenyne motifs via selective M&M cascade reactions.
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Affiliation(s)
- Cheol Kang
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Seongyeon Kwon
- Department of Chemistry , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations , Institute for Basic Science (IBS) , Daejeon 34141 , Republic of Korea
| | - Jong-Chan Sung
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
| | - Jinwoo Kim
- Department of Chemistry , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations , Institute for Basic Science (IBS) , Daejeon 34141 , Republic of Korea
| | - Mu-Hyun Baik
- Department of Chemistry , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea.,Center for Catalytic Hydrocarbon Functionalizations , Institute for Basic Science (IBS) , Daejeon 34141 , Republic of Korea
| | - Tae-Lim Choi
- Department of Chemistry , Seoul National University , Seoul 08826 , Republic of Korea
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5
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Jung K, Kim K, Sung JC, Ahmed TS, Hong SH, Grubbs RH, Choi TL. Toward Perfect Regiocontrol for β-Selective Cyclopolymerization Using a Ru-Based Olefin Metathesis Catalyst. Macromolecules 2018. [DOI: 10.1021/acs.macromol.8b00969] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Kijung Jung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Kunsoon Kim
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Jong-Chan Sung
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Tonia S. Ahmed
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Soon Hyeok Hong
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Robert H. Grubbs
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
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6
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Li H, Wang J, Han H, Wu J, Xie M. Dual conductivity of ionic polyacetylene by the metathesis cyclopolymerization of dendronized triazolium-functionalized 1,6-heptadiyne. REACT FUNCT POLYM 2018. [DOI: 10.1016/j.reactfunctpolym.2018.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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7
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Kang C, Park H, Lee JK, Choi TL. Cascade Polymerization via Controlled Tandem Olefin Metathesis/Metallotropic 1,3-Shift Reactions for the Synthesis of Fully Conjugated Polyenynes. J Am Chem Soc 2017; 139:11309-11312. [DOI: 10.1021/jacs.7b04913] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cheol Kang
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Hyeon Park
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jin-Kyung Lee
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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8
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Imbrich DA, Elser I, Frey W, Buchmeiser MR. First Neutral and Cationic Tungsten Imido Alkylidene N
-Heterocyclic Carbene Complexes. ChemCatChem 2017. [DOI: 10.1002/cctc.201700189] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Dominik A. Imbrich
- Insitute of Polymer Chemistry; University of Stuttgart; Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Iris Elser
- Insitute of Polymer Chemistry; University of Stuttgart; Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Wolfgang Frey
- Institute of Organic Chemistry; University of Stuttgart; Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Michael R. Buchmeiser
- Insitute of Polymer Chemistry; University of Stuttgart; Pfaffenwaldring 55 70569 Stuttgart Germany
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9
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Kang C, Kang EH, Choi TL. Successful Cyclopolymerization of 1,6-Heptadiynes Using First-Generation Grubbs Catalyst Twenty Years after Its Invention: Revealing a Comprehensive Picture of Cyclopolymerization Using Grubbs Catalysts. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00488] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Cheol Kang
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Eun-Hye Kang
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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10
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Song JA, Choi TL. Seven-Membered Ring-Forming Cyclopolymerization of 1,8-Nonadiyne Derivatives Using Grubbs Catalysts: Rational Design of Monomers and Insights into the Mechanism for Olefin Metathesis Polymerizations. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00606] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Jung-Ah Song
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Tae-Lim Choi
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
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11
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Prasad S, Achazi K, Böttcher C, Haag R, Sharma SK. Fabrication of nanostructures through self-assembly of non-ionic amphiphiles for biomedical applications. RSC Adv 2017. [DOI: 10.1039/c6ra28654b] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Non-cytotoxic and non-ionic amphiphiles having supramolecular aggregation behavior were synthesized from biocompatible starting materials using a “greener” chemo-enzymatic method.
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Affiliation(s)
- Suchita Prasad
- Department of Chemistry
- University of Delhi
- Delhi 110 007
- India
| | - Katharina Achazi
- Institut für Chemie und Biochemie
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | - Christoph Böttcher
- Forschungszentrum für Elektronenmikroskopie
- Institut für Chemie und Biochemie
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | - Rainer Haag
- Institut für Chemie und Biochemie
- Freie Universität Berlin
- 14195 Berlin
- Germany
| | - Sunil K. Sharma
- Department of Chemistry
- University of Delhi
- Delhi 110 007
- India
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12
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Wu J, Li H, Zhou D, Liao X, Xie M, Sun R. Metathesis cyclopolymerization of substituted 1,6-heptadiyne and dual conductivity of doped polyacetylene bearing branched triazole pendants. ACTA ACUST UNITED AC 2016. [DOI: 10.1002/pola.28430] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Jianhua Wu
- School of Chemistry and Molecular Engineering; East China Normal University; Shanghai 200241 China
| | - Hongfei Li
- School of Chemistry and Molecular Engineering; East China Normal University; Shanghai 200241 China
| | - Dandan Zhou
- School of Chemistry and Molecular Engineering; East China Normal University; Shanghai 200241 China
| | - Xiaojuan Liao
- School of Chemistry and Molecular Engineering; East China Normal University; Shanghai 200241 China
| | - Meiran Xie
- School of Chemistry and Molecular Engineering; East China Normal University; Shanghai 200241 China
| | - Ruyi Sun
- School of Chemistry and Molecular Engineering; East China Normal University; Shanghai 200241 China
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13
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Jung K, Kang EH, Sohn JH, Choi TL. Highly β-Selective Cyclopolymerization of 1,6-Heptadiynes and Ring-Closing Enyne Metathesis Reaction Using Grubbs Z-Selective Catalyst: Unprecedented Regioselectivity for Ru-Based Catalysts. J Am Chem Soc 2016; 138:11227-33. [DOI: 10.1021/jacs.6b05572] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Kijung Jung
- Department
of Chemistry, Seoul National University, Seoul 151-747, Korea
| | - Eun-Hye Kang
- Department
of Chemistry, Seoul National University, Seoul 151-747, Korea
| | - Jeong-Hun Sohn
- Department
of Chemistry, College of Natural Sciences, Chungnam National University, Daejeon 305-764, Korea
| | - Tae-Lim Choi
- Department
of Chemistry, Seoul National University, Seoul 151-747, Korea
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14
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Kang EH, Kang C, Yang S, Oks E, Choi TL. Mechanistic Investigations on the Competition between the Cyclopolymerization and [2 + 2 + 2] Cycloaddition of 1,6-Heptadiyne Derivatives Using Second-Generation Grubbs Catalysts. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01110] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Eun-Hye Kang
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Cheol Kang
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Sanghee Yang
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Elina Oks
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Tae-Lim Choi
- Department
of Chemistry, Seoul National University, Seoul 08826, Korea
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15
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Buchmeiser MR. Recent Advances in the Regio- and Stereospecific Cyclopolymerization of α,ω-Diynes by Tailored Ruthenium Alkylidenes and Molybdenum Imido Alkylidene N-Heterocyclic Carbene Complexes. POLYM REV 2016. [DOI: 10.1080/15583724.2015.1136643] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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16
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Wang J, Li H, Liao X, Xie M, Sun R. Synthesis of triazole-dendronized polyacetylenes by metathesis cyclopolymerization and their conductivity. Polym Chem 2016. [DOI: 10.1039/c6py00724d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dendronized polyacetylenes with triazole-alkyl and triazole-oligo(ethylene glycol) pendants were synthesized, which had a higher ionic conductivity after doping with different ratios of LiTFSI than their intrinsic ones did.
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Affiliation(s)
- Junfang Wang
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Hongfei Li
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Xiaojuan Liao
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Meiran Xie
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
| | - Ruyi Sun
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai
- China
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17
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Herz K, Unold J, Hänle J, Schowner R, Sen S, Frey W, Buchmeiser MR. Mechanism of the Regio- and Stereoselective Cyclopolymerization of 1,6-Hepta- and 1,7-Octadiynes by High Oxidation State Molybdenum–Imidoalkylidene N-Heterocyclic Carbene Initiators. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b01185] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
| | - Jörg Unold
- Institute of Textile
Chemistry and Chemical Fibers, Körschtalstr.
26, D-73770 Denkendorf, Germany
| | | | | | | | | | - Michael R. Buchmeiser
- Institute of Textile
Chemistry and Chemical Fibers, Körschtalstr.
26, D-73770 Denkendorf, Germany
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18
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Guo M, Sun R, Han H, Wu J, Xie M, Liao X. Metathesis Cyclopolymerization of 1,6-Heptadiyne Derivative toward Triphenylamine-Functionalized Polyacetylene with Excellent Optoelectronic Properties and Nanocylinder Morphology. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b00379] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mengfang Guo
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
| | - Ruyi Sun
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
| | - Huijing Han
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
| | - Jianhua Wu
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
| | - Meiran Xie
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
| | - Xiaojuan Liao
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China
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19
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The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2013. Coord Chem Rev 2015. [DOI: 10.1016/j.ccr.2014.09.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Song W, Han H, Wu J, Xie M. A bridge-like polymer synthesized by tandem metathesis cyclopolymerization and acyclic diene metathesis polymerization. Polym Chem 2015. [DOI: 10.1039/c4py01229a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel bridge-like polymer with excellent thermal stability, an ordered ladder-like structure, and a fence-like ribbon morphology was synthesized by tandem metathesis cyclopolymerization and acyclic diene metathesis polymerization.
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Affiliation(s)
- Wei Song
- Department of Chemistry
- East China Normal University
- Shanghai 200241
- China
| | - Huijing Han
- Department of Chemistry
- East China Normal University
- Shanghai 200241
- China
| | - Jianhua Wu
- Department of Chemistry
- East China Normal University
- Shanghai 200241
- China
| | - Meiran Xie
- Department of Chemistry
- East China Normal University
- Shanghai 200241
- China
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21
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Song W, Han H, Liao X, Sun R, Wu J, Xie M. Metathesis Cyclopolymerization of Imidazolium-Functionalized 1,6-Heptadiyne toward Polyacetylene Ionomer. Macromolecules 2014. [DOI: 10.1021/ma501217b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Wei Song
- Department of Chemistry, East China Normal University, Shanghai 200241, China
| | - Huijing Han
- Department of Chemistry, East China Normal University, Shanghai 200241, China
| | - Xiaojuan Liao
- Department of Chemistry, East China Normal University, Shanghai 200241, China
| | - Ruyi Sun
- Department of Chemistry, East China Normal University, Shanghai 200241, China
| | - Jianhua Wu
- Department of Chemistry, East China Normal University, Shanghai 200241, China
| | - Meiran Xie
- Department of Chemistry, East China Normal University, Shanghai 200241, China
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22
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Kang EH, Yu SY, Lee IS, Park SE, Choi TL. Strategies to enhance cyclopolymerization using third-generation Grubbs catalyst. J Am Chem Soc 2014; 136:10508-14. [PMID: 24980051 DOI: 10.1021/ja505471u] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Cyclopolymerization (CP) of 1,6-heptadiyne derivatives using the Grubbs catalysts has been known to afford conjugated polyenes in low yields in dichloromethane (DCM), the most common solvent for olefin metathesis polymerization and a good solvent for typical conjugated polymers. Based on our previous work that showed highly efficient CP using the Grubbs catalysts in tetrahydrofuran (THF), we developed a new polymerization system using weakly coordinating additives with the third-generation Grubbs catalyst in DCM. The polymerization efficiency of various monomers and their controls dramatically increased by adding 3,5-dichloropyridine, yielding polymers with narrow polydispersity indices (PDIs) at low temperatures. These new reaction conditions not only expand the monomer scope by resolving the solubility concerns of conjugated polymers but also more effectively reduced the chain transfer. Consequently, fully conjugated diblock copolymer was successfully prepared. Additionally, kinetic analysis has revealed that low CP efficiency in DCM resulted from the rapid decomposition of the propagating carbene. This decomposition was effectively suppressed by both pyridine additives and THF, suggesting that weakly coordinating additives stabilize the living chain end. Furthermore, we observed that the turnover number of CP was higher at lower temperatures (0-10 °C) than at ambient temperatures, consistent with the understanding that the lifetime of a propagating carbene is greater at lower temperatures. Steric protection was also shown to increase the stability of the propagating carbene, as shown by a higher turnover number for the 3,3-dimethyl-substituted 1,6-heptadiyne compared to the nonfunctionalized monomer.
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Affiliation(s)
- Eun-Hye Kang
- Department of Chemistry, Seoul National University , Seoul, 151-747, Korea
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