The Experts below are selected from a list of 11256 Experts worldwide ranked by ideXlab platform
Jinhan Cho - One of the best experts on this subject based on the ideXlab platform.
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highly conductive paper textile electrodes using Ligand Exchange Reaction induced in situ metallic fusion
ACS Applied Materials & Interfaces, 2019Co-Authors: Sungkun Kang, Donghyeon Nam, Jimin Choi, Donghee Kim, Cheong Hoon Kwon, June Huh, Jinhan ChoAbstract:Here, we report that metal nanoparticle (NP)-based paper/textile electrodes with bulk metallic conductivity can be prepared via organic linker-modulated Ligand Exchange Reaction and in situ room-temperature metallic fusion without additional chemical or thermal treatments. For this study, amine-functionalized molecule linkers instead of bulky polymer linkers were layer-by-layer (LbL)-assembled with tetraoctylammonium bromide (TOABr)-stabilized Au NPs to form Au NP multilayered films. By conversion of the amine groups of the organic molecule linkers from -NH3+ to the -NH2 groups, as well as by a decrease in the size of the organic linkers, the LbL-assembled Au NPs became highly interconnected and fused during LbL deposition, resulting in Au NP multilayers with adjustable conductivity and transport behavior. These phenomena were also predicted by a density functional theory investigation for the model system. Particularly, LbL-assembled films composed of TOABr-Au NPs and diethylenetriamine ( Mw: ∼104) exhibited a remarkable electrical conductivity of 2.2 × 105 S·cm-1, which was higher than the electrical conductivity of the metal NP-based electrodes as well as the carbon material-based electrodes reported to date. Furthermore, based on our approach, a variety of insulating flexible papers and textiles were successfully converted into real metal-like paper and textile electrodes with high flexibility preserving their highly porous structure. This approach can provide a basis for further improving and controlling the electrical properties of flexible electrodes through the control of organic linkers.
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Highly Conductive Paper/Textile Electrodes Using Ligand Exchange Reaction-Induced in Situ Metallic Fusion
2019Co-Authors: Sungkun Kang, Donghyeon Nam, Jimin Choi, Donghee Kim, Cheong Hoon Kwon, June Huh, Jinhan ChoAbstract:Here, we report that metal nanoparticle (NP)-based paper/textile electrodes with bulk metallic conductivity can be prepared via organic linker-modulated Ligand Exchange Reaction and in situ room-temperature metallic fusion without additional chemical or thermal treatments. For this study, amine-functionalized molecule linkers instead of bulky polymer linkers were layer-by-layer (LbL)-assembled with tetraoctylammonium bromide (TOABr)-stabilized Au NPs to form Au NP multilayered films. By conversion of the amine groups of the organic molecule linkers from −NH3+ to the −NH2 groups, as well as by a decrease in the size of the organic linkers, the LbL-assembled Au NPs became highly interconnected and fused during LbL deposition, resulting in Au NP multilayers with adjustable conductivity and transport behavior. These phenomena were also predicted by a density functional theory investigation for the model system. Particularly, LbL-assembled films composed of TOABr-Au NPs and diethylenetriamine (Mw: ∼104) exhibited a remarkable electrical conductivity of 2.2 × 105 S·cm–1, which was higher than the electrical conductivity of the metal NP-based electrodes as well as the carbon material-based electrodes reported to date. Furthermore, based on our approach, a variety of insulating flexible papers and textiles were successfully converted into real metal-like paper and textile electrodes with high flexibility preserving their highly porous structure. This approach can provide a basis for further improving and controlling the electrical properties of flexible electrodes through the control of organic linkers
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amphiphilic Ligand Exchange Reaction induced supercapacitor electrodes with high volumetric and scalable areal capacitances
Applied Surface Science, 2018Co-Authors: Donghyeon Nam, Yeongbeom Heo, Sanghyuk Cheong, Jinhan ChoAbstract:Abstract We introduce high-performance supercapacitor electrodes with ternary components prepared from consecutive amphiphilic Ligand-Exchange-based layer-by-layer (LbL) assembly among amine-functionalized multi-walled carbon nanotubes (NH2-MWCNTs) in alcohol, oleic acid-stabilized Fe3O4 nanoparticles (OA-Fe3O4 NPs) in toluene, and semiconducting polymers (PEDOT:PSS) in water. The periodic insertion of semiconducting polymers within the (OA-Fe3O4 NP/NH2-MWCNT)n multilayer-coated indium tin oxide (ITO) electrode enhanced the volumetric and areal capacitances up to 408 ± 4 F cm−3 and 8.79 ± 0.06 mF cm−2 at 5 mV s−1, respectively, allowing excellent cycling stability (98.8% of the initial capacitance after 5000 cycles) and good rate capability. These values were higher than those of the OA-Fe3O4 NP/NH2-MWCNT multilayered electrode without semiconducting polymer linkers (volumetric capacitance ∼241 ± 4 F cm−3 and areal capacitance ∼1.95 ± 0.03 mF cm−2) at the same scan rate. Furthermore, when the asymmetric supercapacitor cells (ASCs) were prepared using OA-Fe3O4 NP- and OA-MnO NP-based ternary component electrodes, they displayed high volumetric energy (0.36 mW h cm−3) and power densities (820 mW cm−3).
Tsuyoshi Satoh - One of the best experts on this subject based on the ideXlab platform.
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Ligand Exchange Reaction of sulfoxides in organic synthesis sulfoxide version of the julia lythgoe olefination
Tetrahedron Letters, 1998Co-Authors: Tsuyoshi Satoh, Noriko Yamada, Tohru AsanoAbstract:Abstract Reaction of β-mesyloxy sulfoxides, derived from alkyl (or arylmethyl) phenyl sulfoxides and aldehydes in two steps, with alkylmetal ( n -BuLi, t -BuLi, or EtMgBr) at −78 °C gave olefins in good to excellent yields. This Reaction offers a sulfoxide version of the Julia-Lythgoe olefination.
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generation of aziridinyllithiums from sulfinylaziridines by the Ligand Exchange Reaction of sulfoxides with tert butyllithium their properties and an application to asymmetric synthesis of α dialkylamino acid ester
Tetrahedron Letters, 1998Co-Authors: Tsuyoshi Satoh, Masaki Ozawa, Koji Takano, Masabumi KudoAbstract:Abstract Aziridinyllithiums were generated from sulfinylaziridines by the Ligand Exchange Reaction of sulfoxides with tert -butyllithium. The aziridinyllithiums were found to be stable in THF at below −30 °C and reactive with several electrophiles such as carbonyl compounds. Synthesis of an optically active α-dialkylamino acid ester was realized via the aziridinyllithium starting from optically active chloromethyl p -tolyl sulfoxide.
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a new development in organic synthesis with sulfoxides novel synthetic methods through the Ligand Exchange Reaction of sulfoxides
Journal of Synthetic Organic Chemistry Japan, 1996Co-Authors: Tsuyoshi SatohAbstract:The Ligand Exchange Reaction of sulfoxides with alkylmetals has been known over 40 years. However, this Reaction has scarcely been received attention by chemists. This review deals with the chemistry of Ligand Exchange Reaction of sulfoxides comprehensively and also describes recent new synthetic methods via the Ligand Exchange Reaction. The topics in this review are as follows; 1) the discovery of the Ligand Exchange Reaction of sulfoxides, 2) S-aryl bond-cleavage via the Ligand Exchange, 3) S-alkenyl bond-cleavage via the Ligand Exchange, 4) S-alkyl bond-cleavage via the Ligand Exchange and new synthetic methods, 5) generation of carbenoids via the Ligand Exchange and new synthetic methods, 6) overview.
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Ligand Exchange Reaction of sulfoxides in organic synthesis a novel method for synthesizing acetylenes and allenes from carbonyl compounds through sulfoxides having a trifluoro methanesulfonyloxy group on the β carbon
Tetrahedron, 1995Co-Authors: Tsuyoshi Satoh, Norifumi Itoh, Shizue Watanabe, Haruko Matsuno, Hirofumi Koike, Kenji Matsuda, Koji YamakawaAbstract:Abstract A novel method for synthesizing acetylenes and allenes from carbonyl compounds is described. Ligand Exchange Reaction of alkenylsulfoxides having a trifluoromethanesulfonyloxy group on the β-carbon, which were derived from α-alkyl β-ketosulfoxides, with n-BuLi gave disubstituted acetylenes in good yields. In the case of alkenylsulfoxides having both the trifluoromethanesulfonyloxy and aryl groups on the β-carbon, aryl acetylenes were obtained without treatment with n-BuLi. On the other hand, the enol triflates derived from α, α-dialkyl β-ketosulfoxides gave trisubstituted allenes on treatment with n-BuLi. This procedure was applied to the synthesis of chloroacetylenes, macrocyclic acetylenes and macrocyclic allenes.
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Ligand Exchange Reaction of sulfoxides in organic synthesis: A new synthesis of α-chloroketones from carbonyl compounds with one-carbon homologation
Tetrahedron, 1995Co-Authors: Tsuyoshi Satoh, Yasuhiro Mizu, Taku Kawashima, Koji YamakawaAbstract:Abstract A new procedure for one-carbon homologation of carbonyl compounds to α-chloroketones is described. Addition of the carbanion of dichloromethyl phenyl sulfoxide with ketones and aldehydes gave the adducts, chloro alcohols, in good yields. Treatment of the chloro alcohols with EtMgBr or lithium diisopropylamide gave one-carbon homologated α-chloroketones via β-oxido carbenoid rearrangement in moderate to good yields. One-carbon homologation of esters to α-chloroketones was realized via the Ligand Exchange Reaction of the sulfinyl group of α-chloro α-sulfinyl ketones, which were synthesized from methyl esters and chloromethyl phenyl sulfoxide, with EtMgBr.
Guangqiang Yin - One of the best experts on this subject based on the ideXlab platform.
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supramolecular transformation of metallacycle linked star polymers driven by simple phosphine Ligand Exchange Reaction
Journal of the American Chemical Society, 2019Co-Authors: Wei Zheng, Wei Wang, Shuting Jiang, Guang Yang, Xuqing Wang, Guangqiang Yin, Ying Zhang, Hongwei Tan, Hongming DingAbstract:As a common phenomenon in biological systems, supramolecular transformations of biomacromolecules lead to specific biological functions as outputs, which thus inspire people to construct biomimetic dynamic systems through supramolecular transformation strategy. It should be noted that well-modulating the artificial macromolecules to fine-tune their properties is of great significance yet still remains a big challenge in polymer chemistry. In this study, through the combination of coordination-driven self-assembly and postassembly ring-opening polymerization, a six-armed star polymer linked by well-defined hexagonal metallacycle as core was successfully prepared. At the same time, the trans-platinum acetylide moieties as transformation sites were anchored onto the discrete metallacycle scaffold. Subsequently, the simple phosphine Ligand-Exchange Reaction induced the conversions of platinum acetylide building blocks with the varied binding angles, which thus resulted in the successive hexagon–rhomboid–hexag...
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Supramolecular Transformation of Metallacycle-linked Star Polymers Driven by Simple Phosphine Ligand-Exchange Reaction
2018Co-Authors: Wei Zheng, Wei Wang, Shuting Jiang, Guang Yang, Xuqing Wang, Guangqiang Yin, Ying Zhang, Hongwei TanAbstract:As a common phenomenon in biological systems, supramolecular transformations of biomacromolecules lead to specific biological functions as outputs, which thus inspire people to construct biomimetic dynamic systems through supramolecular transformation strategy. It should be noted that well-modulating the artificial macromolecules to fine-tune their properties is of great significance yet still remains a big challenge in polymer chemistry. In this study, through the combination of coordination-driven self-assembly and postassembly ring-opening polymerization, a six-armed star polymer linked by well-defined hexagonal metallacycle as core was successfully prepared. At the same time, the trans-platinum acetylide moieties as transformation sites were anchored onto the discrete metallacycle scaffold. Subsequently, the simple phosphine Ligand-Exchange Reaction induced the conversions of platinum acetylide building blocks with the varied binding angles, which thus resulted in the successive hexagon–rhomboid–hexagon transformations of metallacyclic scaffold, therefore allowing for the corresponding supramolecular transformation of metallacycle-linked star polymers. More importantly, accompanied by such transformation process, property modulation of the resultant polymers has been successfully realized. In a word, by taking advantage of dynamic nature of metal–Ligand coordination bonds and simple phosphine Ligand-Exchange Reactions, facile architecture transformation of a star polymer to a linear polymer and back to a star polymer was successfully realized, which may provide a promising approach toward the construction of new dynamic polymeric materials
Hongming Ding - One of the best experts on this subject based on the ideXlab platform.
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supramolecular transformation of metallacycle linked star polymers driven by simple phosphine Ligand Exchange Reaction
Journal of the American Chemical Society, 2019Co-Authors: Wei Zheng, Wei Wang, Shuting Jiang, Guang Yang, Xuqing Wang, Guangqiang Yin, Ying Zhang, Hongwei Tan, Hongming DingAbstract:As a common phenomenon in biological systems, supramolecular transformations of biomacromolecules lead to specific biological functions as outputs, which thus inspire people to construct biomimetic dynamic systems through supramolecular transformation strategy. It should be noted that well-modulating the artificial macromolecules to fine-tune their properties is of great significance yet still remains a big challenge in polymer chemistry. In this study, through the combination of coordination-driven self-assembly and postassembly ring-opening polymerization, a six-armed star polymer linked by well-defined hexagonal metallacycle as core was successfully prepared. At the same time, the trans-platinum acetylide moieties as transformation sites were anchored onto the discrete metallacycle scaffold. Subsequently, the simple phosphine Ligand-Exchange Reaction induced the conversions of platinum acetylide building blocks with the varied binding angles, which thus resulted in the successive hexagon–rhomboid–hexag...
Wei Zheng - One of the best experts on this subject based on the ideXlab platform.
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supramolecular transformation of metallacycle linked star polymers driven by simple phosphine Ligand Exchange Reaction
Journal of the American Chemical Society, 2019Co-Authors: Wei Zheng, Wei Wang, Shuting Jiang, Guang Yang, Xuqing Wang, Guangqiang Yin, Ying Zhang, Hongwei Tan, Hongming DingAbstract:As a common phenomenon in biological systems, supramolecular transformations of biomacromolecules lead to specific biological functions as outputs, which thus inspire people to construct biomimetic dynamic systems through supramolecular transformation strategy. It should be noted that well-modulating the artificial macromolecules to fine-tune their properties is of great significance yet still remains a big challenge in polymer chemistry. In this study, through the combination of coordination-driven self-assembly and postassembly ring-opening polymerization, a six-armed star polymer linked by well-defined hexagonal metallacycle as core was successfully prepared. At the same time, the trans-platinum acetylide moieties as transformation sites were anchored onto the discrete metallacycle scaffold. Subsequently, the simple phosphine Ligand-Exchange Reaction induced the conversions of platinum acetylide building blocks with the varied binding angles, which thus resulted in the successive hexagon–rhomboid–hexag...
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Supramolecular Transformation of Metallacycle-linked Star Polymers Driven by Simple Phosphine Ligand-Exchange Reaction
2018Co-Authors: Wei Zheng, Wei Wang, Shuting Jiang, Guang Yang, Xuqing Wang, Guangqiang Yin, Ying Zhang, Hongwei TanAbstract:As a common phenomenon in biological systems, supramolecular transformations of biomacromolecules lead to specific biological functions as outputs, which thus inspire people to construct biomimetic dynamic systems through supramolecular transformation strategy. It should be noted that well-modulating the artificial macromolecules to fine-tune their properties is of great significance yet still remains a big challenge in polymer chemistry. In this study, through the combination of coordination-driven self-assembly and postassembly ring-opening polymerization, a six-armed star polymer linked by well-defined hexagonal metallacycle as core was successfully prepared. At the same time, the trans-platinum acetylide moieties as transformation sites were anchored onto the discrete metallacycle scaffold. Subsequently, the simple phosphine Ligand-Exchange Reaction induced the conversions of platinum acetylide building blocks with the varied binding angles, which thus resulted in the successive hexagon–rhomboid–hexagon transformations of metallacyclic scaffold, therefore allowing for the corresponding supramolecular transformation of metallacycle-linked star polymers. More importantly, accompanied by such transformation process, property modulation of the resultant polymers has been successfully realized. In a word, by taking advantage of dynamic nature of metal–Ligand coordination bonds and simple phosphine Ligand-Exchange Reactions, facile architecture transformation of a star polymer to a linear polymer and back to a star polymer was successfully realized, which may provide a promising approach toward the construction of new dynamic polymeric materials