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Yasushi Nishihara - One of the best experts on this subject based on the ideXlab platform.
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Vinylene-bridged difluorobenzo[c][1,2,5]-thiadiazole (FBTzE): a new electron-deficient building block for high-performance semiconducting polymers in organic electronics
Journal of Materials Chemistry C, 2019Co-Authors: Yuya Asanuma, Hiroki Mori, Ryosuke Takahashi, Yasushi NishiharaAbstract:A new class of an acceptor unit, vinylene-bridged 5,6-difluorobenzothiadiazole FBTzE, has been developed. Palladium-catalyzed Migita–Kosugi–Stille Coupling reactions of 1 with 2, yielding 3 and its sequential dehydrogenative Coupling with 4, readily afforded FBTzE-containing monomers 5a–5c that have lower lowest unoccupied molecular orbital (LUMO) energy level and smaller energy gap than those of 5,6-difluorobenzothiadiazole (DFBT). Subsequently, three types of FBTzE-containing copolymers 3T, 4T, and 2TTT were synthesized by Migita–Kosugi–Stille Coupling of monomers 5b and 5c with distannylated thiophene, bithiophene, and thienothiophene, respectively and their physicochemical properties and solar cell performances were evaluated. As a result of cyclic voltammogram, the synthesized FBTzE-based polymers have deeper highest occupied molecular orbital (HOMO) and LUMO energy levels, and stronger intermolecular interactions than those of DFBT-based polymer PffBT4T-DT. Although 3T/PC61BM blended film formed favorable face-on orientation with short dπ of 3.57 A, its solar cell showed poor PCE of 2.7% owing to the construction of large phase separation structure with a domain size over 100 nm. In a sharp contrast, 2TTT/PC61BM formed unsuitable edge-on orientation with short dπ of 3.49 A, but its film formed optimal nanoscale phase separation, leading to a good performance with PCE of up to 5.2%.
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Phenanthrodithiophene (PDT)–Difluorobenzothiadiazole (DFBT) Copolymers: Effect on Molecular Orientation and Solar Cell Performance of Alkyl Substitution onto a PDT Core
Macromolecules, 2018Co-Authors: Hiroki Mori, Ryosuke Takahashi, Keita Hyodo, Shuhei Nishinaga, Yuta Sawanaka, Yasushi NishiharaAbstract:Synthesis, characterization, and solar cell application of three 4,7-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene (PDT)–difluorobenzothiadiazole (DFBT copolymers (P1–P3) with different linear alkyl side chains to improve solubility, molecular weight, and molecular orientation are described. The utilization of Ir-catalyzed direct borylation and sequential functionalization can selectively afford the target 4,7-dialkylated PDT as the monomers. Migita–Kosugi–Stille Coupling in the presence of CuI can accelerate polymerization to afford high-molecular-weight polymers along with their improved solubility. The effect of alkyl substitution at the 4,7-positions on the electronic structure of PDT–DFBT copolymers is negligible. By installation of additional alkyl chains at the 4,7-positions of PDT, the synthesized polymers P1–P3 have lower intermolecular interaction than that of nonalkylated P0, but they still maintained aggregation behavior in solution. In addition, they formed a favorable face-on orientation w...
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Phenanthrodithiophene (PDT)–Difluorobenzothiadiazole (DFBT) Copolymers: Effect on Molecular Orientation and Solar Cell Performance of Alkyl Substitution onto a PDT Core
2018Co-Authors: Hiroki Mori, Ryosuke Takahashi, Keita Hyodo, Shuhei Nishinaga, Yuta Sawanaka, Yasushi NishiharaAbstract:Synthesis, characterization, and solar cell application of three 4,7-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene (PDT)–difluorobenzothiadiazole (DFBT copolymers (P1–P3) with different linear alkyl side chains to improve solubility, molecular weight, and molecular orientation are described. The utilization of Ir-catalyzed direct borylation and sequential functionalization can selectively afford the target 4,7-dialkylated PDT as the monomers. Migita–Kosugi–Stille Coupling in the presence of CuI can accelerate polymerization to afford high-molecular-weight polymers along with their improved solubility. The effect of alkyl substitution at the 4,7-positions on the electronic structure of PDT–DFBT copolymers is negligible. By installation of additional alkyl chains at the 4,7-positions of PDT, the synthesized polymers P1–P3 have lower intermolecular interaction than that of nonalkylated P0, but they still maintained aggregation behavior in solution. In addition, they formed a favorable face-on orientation with a short π-stacking distance of 3.6 Å, which can enhance their carrier transport ability, resulting in high Jsc and FF. As a result, their fabricated solar cells reached a PCE exceeding 6%, which are about 1.7-fold higher than that of P0. Comparison of alkyl side chain length at the 4,7-positions of PDT revealed that all polymers formed a predominantly face-on orientation and have a similar face-on ratio in blended films, but their crystallinity was decreased as the carbon chains at the 4,7-positions of PDT became shorter. On the other hand, the polymers with short alkyl side chains tended to have low surface roughness and small domain size of active layers, which is an ideal phase separation structure for high-performance PSCs. From these results, it could be seen that the polymers have a trade-off relationship between their domain size and crystallinity, but the impact of alkyl side chain length on their photovoltaic properties is rather small. Thus, the construction of face-on orientation is highly important to achieve a high PCE. Among three polymers, the P3/PC61BM-based solar cell with an optimal nanoscale phase separation structure with bicontinuous domain showed the highest PCE of up to 6.6%
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Mechanisms and Fundamental Reactions
Lecture Notes in Chemistry, 2012Co-Authors: Masayuki Iwasaki, Yasushi NishiharaAbstract:It is widely accepted that the catalytic cycle of cross-Coupling reactions of organometallic reagents with aryl halides catalyzed by transition metals consists of three fundamental processes: oxidative addition, transmetalation, and reductive elimination. Although the details of oxidative addition and reductive elimination have been extensively studied, little research on detailed mechanisms for transmetalation has been exploited until recently. In this chapter, recent examples of the transmetalation process (a transfer of organic groups to palladium) are generally outlined, vis-a-vis the intermediate complexes after transmetalation in Suzuki–Miyaura Coupling and the effect of added copper salts in Migita–Kosugi–Stille Coupling.
Hiroki Mori - One of the best experts on this subject based on the ideXlab platform.
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Vinylene-bridged difluorobenzo[c][1,2,5]-thiadiazole (FBTzE): a new electron-deficient building block for high-performance semiconducting polymers in organic electronics
Journal of Materials Chemistry C, 2019Co-Authors: Yuya Asanuma, Hiroki Mori, Ryosuke Takahashi, Yasushi NishiharaAbstract:A new class of an acceptor unit, vinylene-bridged 5,6-difluorobenzothiadiazole FBTzE, has been developed. Palladium-catalyzed Migita–Kosugi–Stille Coupling reactions of 1 with 2, yielding 3 and its sequential dehydrogenative Coupling with 4, readily afforded FBTzE-containing monomers 5a–5c that have lower lowest unoccupied molecular orbital (LUMO) energy level and smaller energy gap than those of 5,6-difluorobenzothiadiazole (DFBT). Subsequently, three types of FBTzE-containing copolymers 3T, 4T, and 2TTT were synthesized by Migita–Kosugi–Stille Coupling of monomers 5b and 5c with distannylated thiophene, bithiophene, and thienothiophene, respectively and their physicochemical properties and solar cell performances were evaluated. As a result of cyclic voltammogram, the synthesized FBTzE-based polymers have deeper highest occupied molecular orbital (HOMO) and LUMO energy levels, and stronger intermolecular interactions than those of DFBT-based polymer PffBT4T-DT. Although 3T/PC61BM blended film formed favorable face-on orientation with short dπ of 3.57 A, its solar cell showed poor PCE of 2.7% owing to the construction of large phase separation structure with a domain size over 100 nm. In a sharp contrast, 2TTT/PC61BM formed unsuitable edge-on orientation with short dπ of 3.49 A, but its film formed optimal nanoscale phase separation, leading to a good performance with PCE of up to 5.2%.
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Phenanthrodithiophene (PDT)–Difluorobenzothiadiazole (DFBT) Copolymers: Effect on Molecular Orientation and Solar Cell Performance of Alkyl Substitution onto a PDT Core
Macromolecules, 2018Co-Authors: Hiroki Mori, Ryosuke Takahashi, Keita Hyodo, Shuhei Nishinaga, Yuta Sawanaka, Yasushi NishiharaAbstract:Synthesis, characterization, and solar cell application of three 4,7-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene (PDT)–difluorobenzothiadiazole (DFBT copolymers (P1–P3) with different linear alkyl side chains to improve solubility, molecular weight, and molecular orientation are described. The utilization of Ir-catalyzed direct borylation and sequential functionalization can selectively afford the target 4,7-dialkylated PDT as the monomers. Migita–Kosugi–Stille Coupling in the presence of CuI can accelerate polymerization to afford high-molecular-weight polymers along with their improved solubility. The effect of alkyl substitution at the 4,7-positions on the electronic structure of PDT–DFBT copolymers is negligible. By installation of additional alkyl chains at the 4,7-positions of PDT, the synthesized polymers P1–P3 have lower intermolecular interaction than that of nonalkylated P0, but they still maintained aggregation behavior in solution. In addition, they formed a favorable face-on orientation w...
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Phenanthrodithiophene (PDT)–Difluorobenzothiadiazole (DFBT) Copolymers: Effect on Molecular Orientation and Solar Cell Performance of Alkyl Substitution onto a PDT Core
2018Co-Authors: Hiroki Mori, Ryosuke Takahashi, Keita Hyodo, Shuhei Nishinaga, Yuta Sawanaka, Yasushi NishiharaAbstract:Synthesis, characterization, and solar cell application of three 4,7-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene (PDT)–difluorobenzothiadiazole (DFBT copolymers (P1–P3) with different linear alkyl side chains to improve solubility, molecular weight, and molecular orientation are described. The utilization of Ir-catalyzed direct borylation and sequential functionalization can selectively afford the target 4,7-dialkylated PDT as the monomers. Migita–Kosugi–Stille Coupling in the presence of CuI can accelerate polymerization to afford high-molecular-weight polymers along with their improved solubility. The effect of alkyl substitution at the 4,7-positions on the electronic structure of PDT–DFBT copolymers is negligible. By installation of additional alkyl chains at the 4,7-positions of PDT, the synthesized polymers P1–P3 have lower intermolecular interaction than that of nonalkylated P0, but they still maintained aggregation behavior in solution. In addition, they formed a favorable face-on orientation with a short π-stacking distance of 3.6 Å, which can enhance their carrier transport ability, resulting in high Jsc and FF. As a result, their fabricated solar cells reached a PCE exceeding 6%, which are about 1.7-fold higher than that of P0. Comparison of alkyl side chain length at the 4,7-positions of PDT revealed that all polymers formed a predominantly face-on orientation and have a similar face-on ratio in blended films, but their crystallinity was decreased as the carbon chains at the 4,7-positions of PDT became shorter. On the other hand, the polymers with short alkyl side chains tended to have low surface roughness and small domain size of active layers, which is an ideal phase separation structure for high-performance PSCs. From these results, it could be seen that the polymers have a trade-off relationship between their domain size and crystallinity, but the impact of alkyl side chain length on their photovoltaic properties is rather small. Thus, the construction of face-on orientation is highly important to achieve a high PCE. Among three polymers, the P3/PC61BM-based solar cell with an optimal nanoscale phase separation structure with bicontinuous domain showed the highest PCE of up to 6.6%
Shingo Ishikawa - One of the best experts on this subject based on the ideXlab platform.
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Pd‐Catalyzed Tandem sp2—sp3 Coupling Reactions of Chiral Stannolanes: An Efficient Preparation of Optically Active Tetrahydrobenz[f]isoindoles.
ChemInform, 2013Co-Authors: Akio Kamimura, Masahiro So, Shingo IshikawaAbstract:Dihydrostannolanes (I), readily available by a radical cascade reaction, undergo a novel double Migita-Kosugi-Stille Coupling reaction with dihalobenzenes in the presence of a palladium catalyst.
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Pd-catalyzed tandem sp2-sp3 Coupling reactions of chiral stannolanes: an efficient preparation of optically active tetrahydrobenz[f]isoindoles.
Organic Letters, 2013Co-Authors: Akio Kamimura, Masahiro So, Shingo IshikawaAbstract:A novel double Migita–Kosugi–Stille Coupling reaction with dihydrostannolanes, which are readily available from a radical cascade reaction, was achieved with dihalobenzenes in the presence of a palladium catalyst. Use of unsymmetrical 1-bromo-2-iodobenzene derivatives accomplished the double Coupling reaction which gave tetrahydrobenz[f]isoindoles in a regioselective manner.
Ryosuke Takahashi - One of the best experts on this subject based on the ideXlab platform.
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Vinylene-bridged difluorobenzo[c][1,2,5]-thiadiazole (FBTzE): a new electron-deficient building block for high-performance semiconducting polymers in organic electronics
Journal of Materials Chemistry C, 2019Co-Authors: Yuya Asanuma, Hiroki Mori, Ryosuke Takahashi, Yasushi NishiharaAbstract:A new class of an acceptor unit, vinylene-bridged 5,6-difluorobenzothiadiazole FBTzE, has been developed. Palladium-catalyzed Migita–Kosugi–Stille Coupling reactions of 1 with 2, yielding 3 and its sequential dehydrogenative Coupling with 4, readily afforded FBTzE-containing monomers 5a–5c that have lower lowest unoccupied molecular orbital (LUMO) energy level and smaller energy gap than those of 5,6-difluorobenzothiadiazole (DFBT). Subsequently, three types of FBTzE-containing copolymers 3T, 4T, and 2TTT were synthesized by Migita–Kosugi–Stille Coupling of monomers 5b and 5c with distannylated thiophene, bithiophene, and thienothiophene, respectively and their physicochemical properties and solar cell performances were evaluated. As a result of cyclic voltammogram, the synthesized FBTzE-based polymers have deeper highest occupied molecular orbital (HOMO) and LUMO energy levels, and stronger intermolecular interactions than those of DFBT-based polymer PffBT4T-DT. Although 3T/PC61BM blended film formed favorable face-on orientation with short dπ of 3.57 A, its solar cell showed poor PCE of 2.7% owing to the construction of large phase separation structure with a domain size over 100 nm. In a sharp contrast, 2TTT/PC61BM formed unsuitable edge-on orientation with short dπ of 3.49 A, but its film formed optimal nanoscale phase separation, leading to a good performance with PCE of up to 5.2%.
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Phenanthrodithiophene (PDT)–Difluorobenzothiadiazole (DFBT) Copolymers: Effect on Molecular Orientation and Solar Cell Performance of Alkyl Substitution onto a PDT Core
Macromolecules, 2018Co-Authors: Hiroki Mori, Ryosuke Takahashi, Keita Hyodo, Shuhei Nishinaga, Yuta Sawanaka, Yasushi NishiharaAbstract:Synthesis, characterization, and solar cell application of three 4,7-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene (PDT)–difluorobenzothiadiazole (DFBT copolymers (P1–P3) with different linear alkyl side chains to improve solubility, molecular weight, and molecular orientation are described. The utilization of Ir-catalyzed direct borylation and sequential functionalization can selectively afford the target 4,7-dialkylated PDT as the monomers. Migita–Kosugi–Stille Coupling in the presence of CuI can accelerate polymerization to afford high-molecular-weight polymers along with their improved solubility. The effect of alkyl substitution at the 4,7-positions on the electronic structure of PDT–DFBT copolymers is negligible. By installation of additional alkyl chains at the 4,7-positions of PDT, the synthesized polymers P1–P3 have lower intermolecular interaction than that of nonalkylated P0, but they still maintained aggregation behavior in solution. In addition, they formed a favorable face-on orientation w...
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Phenanthrodithiophene (PDT)–Difluorobenzothiadiazole (DFBT) Copolymers: Effect on Molecular Orientation and Solar Cell Performance of Alkyl Substitution onto a PDT Core
2018Co-Authors: Hiroki Mori, Ryosuke Takahashi, Keita Hyodo, Shuhei Nishinaga, Yuta Sawanaka, Yasushi NishiharaAbstract:Synthesis, characterization, and solar cell application of three 4,7-dialkylated phenanthro[1,2-b:8,7-b′]dithiophene (PDT)–difluorobenzothiadiazole (DFBT copolymers (P1–P3) with different linear alkyl side chains to improve solubility, molecular weight, and molecular orientation are described. The utilization of Ir-catalyzed direct borylation and sequential functionalization can selectively afford the target 4,7-dialkylated PDT as the monomers. Migita–Kosugi–Stille Coupling in the presence of CuI can accelerate polymerization to afford high-molecular-weight polymers along with their improved solubility. The effect of alkyl substitution at the 4,7-positions on the electronic structure of PDT–DFBT copolymers is negligible. By installation of additional alkyl chains at the 4,7-positions of PDT, the synthesized polymers P1–P3 have lower intermolecular interaction than that of nonalkylated P0, but they still maintained aggregation behavior in solution. In addition, they formed a favorable face-on orientation with a short π-stacking distance of 3.6 Å, which can enhance their carrier transport ability, resulting in high Jsc and FF. As a result, their fabricated solar cells reached a PCE exceeding 6%, which are about 1.7-fold higher than that of P0. Comparison of alkyl side chain length at the 4,7-positions of PDT revealed that all polymers formed a predominantly face-on orientation and have a similar face-on ratio in blended films, but their crystallinity was decreased as the carbon chains at the 4,7-positions of PDT became shorter. On the other hand, the polymers with short alkyl side chains tended to have low surface roughness and small domain size of active layers, which is an ideal phase separation structure for high-performance PSCs. From these results, it could be seen that the polymers have a trade-off relationship between their domain size and crystallinity, but the impact of alkyl side chain length on their photovoltaic properties is rather small. Thus, the construction of face-on orientation is highly important to achieve a high PCE. Among three polymers, the P3/PC61BM-based solar cell with an optimal nanoscale phase separation structure with bicontinuous domain showed the highest PCE of up to 6.6%
Akio Kamimura - One of the best experts on this subject based on the ideXlab platform.
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Pd‐Catalyzed Tandem sp2—sp3 Coupling Reactions of Chiral Stannolanes: An Efficient Preparation of Optically Active Tetrahydrobenz[f]isoindoles.
ChemInform, 2013Co-Authors: Akio Kamimura, Masahiro So, Shingo IshikawaAbstract:Dihydrostannolanes (I), readily available by a radical cascade reaction, undergo a novel double Migita-Kosugi-Stille Coupling reaction with dihalobenzenes in the presence of a palladium catalyst.
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Pd-catalyzed tandem sp2-sp3 Coupling reactions of chiral stannolanes: an efficient preparation of optically active tetrahydrobenz[f]isoindoles.
Organic Letters, 2013Co-Authors: Akio Kamimura, Masahiro So, Shingo IshikawaAbstract:A novel double Migita–Kosugi–Stille Coupling reaction with dihydrostannolanes, which are readily available from a radical cascade reaction, was achieved with dihalobenzenes in the presence of a palladium catalyst. Use of unsymmetrical 1-bromo-2-iodobenzene derivatives accomplished the double Coupling reaction which gave tetrahydrobenz[f]isoindoles in a regioselective manner.