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Mario Leclerc - One of the best experts on this subject based on the ideXlab platform.
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Direct (hetero)arylation Polymerization: toward defect-free conjugated polymers
Polymer Journal, 2020Co-Authors: Mario Leclerc, Samuel Brassard, Serge BeaupréAbstract:In a very short time, direct (hetero)arylation Polymerization (DHAP) has established itself as a valuable and atom-economical alternative to traditional Cross-Coupling methods such as the Migita–Stille and Suzuki-Miyaura Polymerizations for the synthesis of low cost and efficient conjugated polymers for organic electronics. Because of sustained research efforts combining in-depth theoretical calculations, the development of new ligands and the careful fine-tuning of Polymerization conditions, selectivity and reactivity issues should be soon a thing of the past. This focus review highlights the recent advances that lead to defect-free polymeric semiconductors and conductors and the current limitations and challenges of DHAP as it moves toward simultaneously becoming an industrially feasible, environmentally friendly, and synthetically powerful Polymerization technique. The implementation of Direct Heteroarylation Polymerization (DHAP) in the synthesis of well-defined and defect-free materials for organic electronics is still in its early stages but giant leaps have been made over the past few years to improve and stir the selectivity of the reaction to avoid unwanted side-reaction such as β-branching or homocoupling. DHAP has proven to be an efficient, cost-effective, green and scalable Polymerization method now competing or even surpassing well-established Suzuki-Miyaura or Migita–Stille Cross-Coupling Polymerization methods. This focus review puts emphasis on the synthetic strategies that made DHAP successful.
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Pyromellitic Diimide-Based Copolymers and Their Application as Stable Cathode Active Materials in Lithium and Sodium-Ion Batteries
Chemistry of Materials, 2018Co-Authors: Nicolas Zindy, J. Terence Blaskovits, Catherine Beaumont, Julien Michaud-valcourt, Hamidreza Saneifar, Paul A. Johnson, Daniel Bélanger, Mario LeclercAbstract:Organic molecules are emerging candidates for the next generation of cost-effective active materials of Li-ion batteries. Small diimide building blocks such as pyromellitic diimide (PMDI) have attracted much attention because of their high theoretical capacity. Many strategies have been undertaken to limit the well-known phenomenon of dissolution of the active material in the electrolyte. Such strategies include the preparation of salts and the synthesis of polyimides or macrocycles. Since dibromopyromellitic dimiide exhibits almost no sp2 Cross-Coupling Polymerization reaction by conventional synthetic routes (Suzuki–Miyaura or Migita–Stille), we used PMDI as an aromatic C–H bond-bearing unit for direct (hetero)arylation Polymerization (DHAP) with 1,4-dibromobenzene as comonomer as a new stabilization strategy. DHAP proved to be an effective tool in the preparation of this polymer, yielding a number-average molecular weight of up to 31 kDa. We studied the effect of side-chain engineering using variable c...
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Pyromellitic Diimide-Based Copolymers and Their Application as Stable Cathode Active Materials in Lithium and Sodium-Ion Batteries
2018Co-Authors: Nicolas Zindy, Catherine Beaumont, Julien Michaud-valcourt, Hamidreza Saneifar, Paul A. Johnson, Terence J. Blaskovits, Daniel Bélanger, Mario LeclercAbstract:Organic molecules are emerging candidates for the next generation of cost-effective active materials of Li-ion batteries. Small diimide building blocks such as pyromellitic diimide (PMDI) have attracted much attention because of their high theoretical capacity. Many strategies have been undertaken to limit the well-known phenomenon of dissolution of the active material in the electrolyte. Such strategies include the preparation of salts and the synthesis of polyimides or macrocycles. Since dibromopyromellitic dimiide exhibits almost no sp2 Cross-Coupling Polymerization reaction by conventional synthetic routes (Suzuki–Miyaura or Migita–Stille), we used PMDI as an aromatic C–H bond-bearing unit for direct (hetero)arylation Polymerization (DHAP) with 1,4-dibromobenzene as comonomer as a new stabilization strategy. DHAP proved to be an effective tool in the preparation of this polymer, yielding a number-average molecular weight of up to 31 kDa. We studied the effect of side-chain engineering using variable chain lengths, cross-linked structures, and thermocleavable functional groups. Practical potential limits of 1.65 to 2.50 V vs Li/Li+, wherein two distinct redox phenomena appear, and a galvanostatic high rate limit of 2C were determined. Galvanostatic measurements at C/20 show a starting normalized capacity of 0.94 decreasing to 0.48 after more than 80 days (50 cycles). A maximum discharge capacity of 73 mAh/g as a first cycle was obtained for a polymer of this family at C/10. Density functional theory calculations were applied to understand the higher corrected redox potentials obtained by cyclic voltammetry for sodium ion over lithium ion batteries
Atsunori Mori - One of the best experts on this subject based on the ideXlab platform.
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One-Shot Deprotonative Metalation/Transmetalation/Polymerization of Halothiophenes Catalyzed by Nickel Complex for Polythiophene Synthesis
Synthesis, 2021Co-Authors: Atsunori Mori, Yushin Shibuya, Toyoko Suzuki, Kentaro Okano, Sonoka Yamamoto, Masaki HorieAbstract:Effect of divalent metals was studied in the Cross-Coupling Polymerization of thiophenes leading to head-to-tail-type poly-3-hexylthiophene. Deprotonation of the C–H bond at the 5-position of 2-halo-3-hexylthiophene by LDA followed by metal exchange was carried out in one pot and following addition of nickel catalyst underwent Polymerization. One-shot reaction involving deprotonation/transmetalation/ cross coupling Polymerization was also examined with manganese(II) chloride and nickel(II) catalyst.
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Thermally Induced Self-Doping of π-Conjugated Polymers Bearing a Pendant Neopentyl Sulfonate Group
Macromolecules, 2020Co-Authors: Atsunori Mori, Toyoko Suzuki, Kentaro Okano, Chihiro Kubota, Keisuke Fujita, Masayasu Hayashi, Tadayuki Ogura, Masahiro Funahashi, Masaki HorieAbstract:A regioregular head-to-tail (HT)-type polythiophene was synthesized by the deprotonative nickel-catalyzed Cross-Coupling Polymerization of 2-chlorothiophene bearing a neopentyl benzenesulfonate gro...
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Unprecedented Regioregular Poly(1,4-arylene)s Prepared by Nickel(II)-Catalyzed Cross-Coupling Polymerization of 2,5-Disubstituted Bromo(chloro)arylene.
Angewandte Chemie (International ed. in English), 2019Co-Authors: Yushin Shibuya, Naoki Nakagawa, Naoki Miyagawa, Toyoko Suzuki, Kentaro Okano, Atsunori MoriAbstract:The unprecedented synthesis of regioregular head-to-tail-type poly(1,4-arylene)s bearing different substituents at the 2- and 5-positions is described. They were prepared by the Polymerization of 2,5-disubstituted bromo(chloro)arylenes by selective halogen-metal exchange with a Grignard reagent and subsequent Cross-Coupling Polymerization with a nickel catalyst [NiCl2 (dppp)]. Formation of the regioregular poly(1,4-arylene)s were confirmed by NMR spectroscopy, and showed remarkable differences to those polymers having uncontrolled regioregularity. Polymerization of bromo(chloro)arylenes with a chiral alkoxy substituent also led to the regioregular head-to-tail-type polyarylene, which demonstrated circular dichroism, thus suggesting formation of a structure with higher-order regularity.
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Linear-selective Cross-Coupling Polymerization of branched oligothiophene by deprotonative metalation and Cross-Coupling
Polymer Chemistry, 2015Co-Authors: Kohei Murakami, Shota Tanaka, Atsunori MoriAbstract:Brominated oligothiophene with a branched structure was subjected to deprotonative metalation with a bulky magnesium amide chloromagnesium 2,2,6,6-tetramethylpiperidine-2-yl lithium chloride salt (TMPMgCl·LiCl), which is known as the Knochel–Hauser base. The thus metalated oligothiophene was polymerized in the presence of a nickel(II) NHC (N-heterocyclic carbene) complex to afford polymers of Mn of 4400 to 44 000, which corresponds well with the monomer feed/catalyst loading ratio. Analysis by MALDI-TOF MS suggests the formation of a linear polymer with oligothiophene as the monomer. Polymerization of 7-mer (7T-Br4) also affords polythiophene of a similar structure.
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11.19 – Cross-Coupling Polymerization
Comprehensive Organometallic Chemistry III, 2007Co-Authors: Atsunori Mori, M.s. Mohamed AhmedAbstract:Cross-Coupling Polymerization reactions are summarized. The reactions include the coupling at metallic species of the sp2-, sp-, and sp3-carbon atoms with a variety of organic electrophiles. The polycondensation using an addition–elimination sequence, multi-component reactions, and carbon–heteroatom bond formation is also described.
Tongmou Geng - One of the best experts on this subject based on the ideXlab platform.
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The influences of the structure of thiophene-based conjugated microporous polymers on the fluorescence sensing properties
New Journal of Chemistry, 2020Co-Authors: Tongmou Geng, Can Zhang, Min Liu, Xie WangAbstract:Three thiophene-based conjugated microporous polymers (CMPs: TTPTh, DBTh, and TBTh) were prepared by Sonogashira–Hagihara Cross-Coupling Polymerization, and their structures were characterized by FTIR, ss 13C NMR, and elemental analyses. The obtained TTPTh, DBTh, and TBTh have excellent thermal stability with decomposition temperatures of 615, 298, and 290 °C and high porosity with BET surface areas of 564.97, 416.99, and 521.30 m2 g−1, respectively. The results reveal that the conjugation of the CMPs plays an essential role in determining the fluorescence sensing performance. Because of the perfect conjugation arising from a low volume of the building block or low degree of cross-linking, DBTh has high fluorescence sensing sensitivity to 2,4-dinitrophenol (DNP) and iodine with Ksv values of 5.76 × 104 and 4.52 × 104 L mol−1 and LODs of 1.56 × 10−10 and 3.32 × 10−12 mol L−1, respectively. To the best of our knowledge, the sensitivity to DNP and iodine of DBTh is the highest among all thiophene-based CMPs reported to date. Our study provides an essential understanding for the structure design of fluorescent sensors of CMPs.
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The effects of the crosslinking position and degree of conjugation in perylene tetraanhydride bisimide microporous polymers on fluorescence sensing performance
RSC Advances, 2020Co-Authors: Ying-chun Gao, Can Zhang, Min Liu, Tongmou GengAbstract:In this study, two fluorescence conjugated microporous polymers based on perylene tetraanhydride bisimide (DP4A0 and DP4A2) were prepared via Sonogashira–Hagihara Cross-Coupling Polymerization for the efficient detection of o-nitrophenol (o-NP). They were well characterized via FT-IR, solid state 13C NMR, elemental analysis, and other material characterization techniques. The experiments proved that both CMPs possess high thermal and chemical stability and a porous nature with Brunauer–Emmett–Teller (BET) specific surface areas of 41.3 and 402.1 m2 g−1. Importantly, owing to signal amplification by the conjugated skeleton, DP4A0 and DP4A2 exhibit extremely high sensitivity to o-NP with Ksv values of 1.83 × 104 and 1.69 × 104 L mol−1 and limits of detection of 5.73 × 10−9 and 7.36 × 10−9 mol L−1, respectively. The sensing performance of DP4A0 and DP4A2 was dependent on the position of crosslinking points and crosslinking density. Finally, super amplified quenching was considered the electron transfer mechanism and hydrogen bond interactions were also present.
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Fluorescent conjugated microporous polymer based on perylene tetraanhydride bisimide for sensing o-nitrophenol
Analytica chimica acta, 2018Co-Authors: Tongmou Geng, Zongming Zhu, Weiyong Zhang, Hai Zhu, Zhuqing WangAbstract:Abstract A novel conjugated microporous polymer based on perylene tetraanhydride bisimide (DP2A2) has been synthesized through Sonogashira–Hagihara Cross-Coupling Polymerization of tetrabromo-substituted perylene tetraanhydride bisimide derivative (DPBr2ABr2) with 1,4-diethynylbenzene, whose Brunauer–Emmett–Teller (BET) specific surface area is about 378 m2 g−1. The fluorescence quenching behaviors of the DP2A2 were investigated. It is found that the DP2A2 shows high sensitivity and selectivity to tracing o-nitrophenol (o-NP) in THF with KsV constant of 2.00 × 104 L mol−1. The detection limit (LOD) is 1.50 × 10−9 mol L−1. The possible sensing mechanism for the luminescent quenching of DP2A2 towards o-NP exciting at 365 nm was considered the donor–acceptor electron transfer mechanism, which is a combined result from both dynamic (collisional) and static quenching. Moreover, the static quenching process is dominant for DP2A2.
Shigeki Habaue - One of the best experts on this subject based on the ideXlab platform.
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Lewis-Acid-Assisted Highly Selective Oxidative Cross-Coupling Polymerization with Copper Catalysts
Polymer Journal, 2008Co-Authors: Pei Yan, Tomohisa Temma, Shigeki HabaueAbstract:An asymmetric oxidative Cross-Coupling Polymerization with a binary catalyst system of an achiral or chiral copper complex and a Lewis acid was investigated. Both the copper and Lewis acid catalysts significantly affected the catalyst activity, Cross-Coupling and stereoselectivities during the Polymerization. The Polymerization of methyl 3,7-dihydroxynaphthalene-2-carboxylate using a copper(I)-bisoxazoline catalyst at room temperature under an O_2 atmosphere in the presence of Yb(OTf)_3 proceeded with a Cross-Coupling selectivity of 97%.
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Catalytic Oxidative Cross-Coupling Polymerization of Unsymmetric Binaphthol Derivatives Using Cu(I)-Bisoxazoline Complexes
Polymer Journal, 2007Co-Authors: Tomohisa Temma, Yusuke Takahashi, Yasuhiro Yoshii, Shigeki HabaueAbstract:The asymmetric oxidative coupling Polymerization of 6,6′-dihydroxy-2,2′-binaphthalene derivatives or methyl 3,7-dihydroxy-2-naphthoate, having an unsymmetric 2-naphthol structure, with copper catalysts under an O_2 atmosphere was carried out. The Polymerization using the CuCl-( S )-2,2′-isopropylidenebis(4-phenyl-2-oxazoline) catalyst afforded a polymer with a high Cross-Coupling selectivity of up to 99%, which showed a number average molecular weight of 5.0–9.1×10^3. To estimate the stereoselectivity during the Polymerization, a model reaction was examined which resulted in good to high Cross-Coupling selectivities, while the enantioselectivities were low. The polymer composed of a homo-coupling unit showed a photoluminescence spectral pattern similar to that of the model compound. In contrast, a very different emission, which may be due to the excimer, from that of the model was observed for the polymer consisted of the Cross-Coupling unit.
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Polymeric Chiral Catalyst Design and Chiral Polymer Synthesis - Synthesis of hyperbranched polymer having binaphthol units via oxidative Cross-Coupling Polymerization
Journal of Polymer Science Part A: Polymer Chemistry, 2007Co-Authors: Tomohisa Temma, Shigeki HabaueAbstract:The oxidative coupling Polymerization of triphenylamine derivatives having 2-naphthol moieties with a CuCl-2,2′-isopropylidenebis(4-phenyl-2-oxazoline) catalyst under an O2 atmosphere was carried out. The Polymerization of the monomer bearing both the hydroxynaphthoate and naphthol units afforded a hyperbranched polymer with a high Cross-Coupling selectivity of > 99%, which showed a number-average molecular weight of 20.3 × 103. In addition, the obtained polymer was quite soluble in THF. The photoluminescence and electrochemical properties of the obtained polymers were also examined. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1034–1041, 2008
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Highly selective oxidative Cross-Coupling Polymerization with copper(I)-bisoxazoline catalysts
Journal of Polymer Science Part A: Polymer Chemistry, 2005Co-Authors: Tomohisa Temma, Shigeki HabaueAbstract:The asymmetric oxidative coupling Polymerization of methyl 6,6'-dihydroxy-2,2'-binaphthalene-7-carboxylate with the copper-diamine catalysts under an O 2 atmosphere was carried out. As is the case with the CuCl-2,2'-(S)-isopropylidenbis(4-phenyl-2-oxazoline) [(S)IPhO] catalyst, a polymer with a high Cross-Coupling selectivity of 96% was obtained in 71% yield, whose THF-soluble part had a number-average molecular weight of 4.5 x 10 3 . To estimate the enantioselectivity with respect to the Cross-Coupling linkage in the obtained polymer, the model asymmetric oxidative Cross-Coupling reaction with CuCl-(S)IPhO was also conducted, and the products showed a 94% Cross-Coupling selectivity and enantioselectivity of 31% ee (S).
Nicolas Zindy - One of the best experts on this subject based on the ideXlab platform.
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Pyromellitic Diimide-Based Copolymers and Their Application as Stable Cathode Active Materials in Lithium and Sodium-Ion Batteries
Chemistry of Materials, 2018Co-Authors: Nicolas Zindy, J. Terence Blaskovits, Catherine Beaumont, Julien Michaud-valcourt, Hamidreza Saneifar, Paul A. Johnson, Daniel Bélanger, Mario LeclercAbstract:Organic molecules are emerging candidates for the next generation of cost-effective active materials of Li-ion batteries. Small diimide building blocks such as pyromellitic diimide (PMDI) have attracted much attention because of their high theoretical capacity. Many strategies have been undertaken to limit the well-known phenomenon of dissolution of the active material in the electrolyte. Such strategies include the preparation of salts and the synthesis of polyimides or macrocycles. Since dibromopyromellitic dimiide exhibits almost no sp2 Cross-Coupling Polymerization reaction by conventional synthetic routes (Suzuki–Miyaura or Migita–Stille), we used PMDI as an aromatic C–H bond-bearing unit for direct (hetero)arylation Polymerization (DHAP) with 1,4-dibromobenzene as comonomer as a new stabilization strategy. DHAP proved to be an effective tool in the preparation of this polymer, yielding a number-average molecular weight of up to 31 kDa. We studied the effect of side-chain engineering using variable c...
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Pyromellitic Diimide-Based Copolymers and Their Application as Stable Cathode Active Materials in Lithium and Sodium-Ion Batteries
2018Co-Authors: Nicolas Zindy, Catherine Beaumont, Julien Michaud-valcourt, Hamidreza Saneifar, Paul A. Johnson, Terence J. Blaskovits, Daniel Bélanger, Mario LeclercAbstract:Organic molecules are emerging candidates for the next generation of cost-effective active materials of Li-ion batteries. Small diimide building blocks such as pyromellitic diimide (PMDI) have attracted much attention because of their high theoretical capacity. Many strategies have been undertaken to limit the well-known phenomenon of dissolution of the active material in the electrolyte. Such strategies include the preparation of salts and the synthesis of polyimides or macrocycles. Since dibromopyromellitic dimiide exhibits almost no sp2 Cross-Coupling Polymerization reaction by conventional synthetic routes (Suzuki–Miyaura or Migita–Stille), we used PMDI as an aromatic C–H bond-bearing unit for direct (hetero)arylation Polymerization (DHAP) with 1,4-dibromobenzene as comonomer as a new stabilization strategy. DHAP proved to be an effective tool in the preparation of this polymer, yielding a number-average molecular weight of up to 31 kDa. We studied the effect of side-chain engineering using variable chain lengths, cross-linked structures, and thermocleavable functional groups. Practical potential limits of 1.65 to 2.50 V vs Li/Li+, wherein two distinct redox phenomena appear, and a galvanostatic high rate limit of 2C were determined. Galvanostatic measurements at C/20 show a starting normalized capacity of 0.94 decreasing to 0.48 after more than 80 days (50 cycles). A maximum discharge capacity of 73 mAh/g as a first cycle was obtained for a polymer of this family at C/10. Density functional theory calculations were applied to understand the higher corrected redox potentials obtained by cyclic voltammetry for sodium ion over lithium ion batteries