Synthesis, Structures, and Properties of Organosilicon Curved sigma-Conjugated Compounds

• Project/Area Number: 18H01960
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 33010:Structural organic chemistry and physical organic chemistry-related
• Research Institution: Gunma University
• Principal Investigator: KYUSHIN Soichiro 群馬大学, 大学院理工学府, 教授 (40195392)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥17,290,000 (Direct Cost: ¥13,300,000、Indirect Cost: ¥3,990,000); Fiscal Year 2020: ¥5,460,000 (Direct Cost: ¥4,200,000、Indirect Cost: ¥1,260,000); Fiscal Year 2019: ¥5,720,000 (Direct Cost: ¥4,400,000、Indirect Cost: ¥1,320,000); Fiscal Year 2018: ¥6,110,000 (Direct Cost: ¥4,700,000、Indirect Cost: ¥1,410,000)
• Keywords: 有機ケイ素化合物 / 曲面σ共役 / かご形オリゴシラン / おわん形オリゴシラン

Outline of Final Research Achievements

The following results were obtained in this research.
1) The charge-transfer complexes of oligosilane dendrimers and an electron acceptor were formed, and their UV/Vis spectra were measured. In order to raise the formation constant, synthesis of bicyclo[4.4.4]tetradecasilane having a large cavity was carried out.
2) Oligosilanes containing a phosphorus atom were synthesized. To clarify how the phosphorus atom affects the σ conjugation systems, their electronic properties were studied by UV spectra and theoretical calculations.

Academic Significance and Societal Importance of the Research Achievements

π共役はp軌道同士が平面上で相互作用することによって発現する現象で、有機化学における基本概念の一つである。最近のかご形化合物やおわん形化合物の研究によって、π共役が平面上だけではなく、曲面上でも発現することが明らかになっている。ところでケイ素化合物ではケイ素－ケイ素結合が相互作用するσ共役が知られているが、曲面上でσ共役化合物がどのような性質を示すかについてはほとんど明らかにされていない。本研究では有機ケイ素曲面σ共役化合物や関連化合物を合成して、その性質を明らかにした。

Research Products

• [Journal Article] Silicon-Silicon π Single Bond (2020)
  • Author(s): Soichiro Kyushin, Yoshikuni Kurosaki, Kyohei Otsuka, Haruna Imai, Shintaro Ishida, Toru Kyomen, Minoru Hanaya, Hideyuki Matsumoto
  • Journal Title: Nature Communications Volume: 11 Issue: 1
  • DOI: 10.1038/s41467-020-17815-z
  • Peer Reviewed / Open Access
• [Journal Article] A Six-Coordinate Silicon Dihydride Embedded in a Porphyrin: Enhanced Hydride-Donor Properties and the Catalyst-Free Hydrosilylation of CO2 (2020)
  • Author(s): Shintaro Ishida, Takuroh Hatakeyama, Takuya Nomura, Maiko Matsumoto, Kimio Yoshimura, Soichiro Kyushin, Takeaki Iwamoto
  • Journal Title: Chemistry - A European Journal Volume: 26 Issue: 68 Pages: 15811-15815
  • DOI: 10.1002/chem.202002587
  • Peer Reviewed
• [Journal Article] Ruthenium-Catalyzed Hydrosilylation of Alkynes by Using Hydrooligosilanes without Si-Si Bond Cleavage (2020)
  • Author(s): Ken-ichiro Kanno, Yumi Aikawa, Soichiro Kyushin
  • Journal Title: Tetrahedron Letters Volume: 61 Issue: 36 Pages: 152274-152274
  • DOI: 10.1016/j.tetlet.2020.152274
  • Peer Reviewed
• [Journal Article] Oxygen-Free Poly(dimethylsilylene) (2020)
  • Author(s): Soichiro Kyushin, Kazuto Mizoguchi, Tomohiro Tanaka, Takeshi Yamanobe, Kenichi Hayashi
  • Journal Title: Organometallics Volume: 39 Issue: 24 Pages: 4651-4656
  • DOI: 10.1021/acs.organomet.0c00674
  • Peer Reviewed
• [Journal Article] Effects of Perpendicular Aryl Groups on Electronic Properties and Complexation of 4,4-Dihydrodithienosilole (2019)
  • Author(s): Akihiro Tsurusaki, Soichiro Kyushin
  • Journal Title: Bulletin of the Chemical Society of Japan Volume: 92 Issue: 6 Pages: 1039-1046
  • DOI: 10.1246/bcsj.20190007
  • NAID: 130007663607
  • Peer Reviewed
• [Journal Article] Stepwise Introduction of Different Substituents to α-Chloro-ω-hydrooligosilanes: Convenient Synthesis of Unsymmetrically Substituted Oligosilanes (2018)
  • Author(s): Ken-ichiro Kanno, Yumi Aikawa, Yuka Niwayama, Misaki Ino, Kento Kawamura, Soichiro Kyushin
  • Journal Title: Inorganics Volume: 6 Issue: 3 Pages: 99-99
  • DOI: 10.3390/inorganics6030099
  • Peer Reviewed / Open Access
• [Journal Article] Synthesis, Structures, and Reactivity of 9,9-Dialkoxy-9-silafluorenes (2018)
  • Author(s): Ken-ichiro Kanno, Satoshi Hirose, Soichiro Kyushin
  • Journal Title: Heteroatom Chemistry Volume: 29 Issue: 5-6
  • DOI: 10.1002/hc.21478
  • Peer Reviewed
• [Presentation] 大きな空孔をもつかご形オリゴシランの合成 (2020)
  • Author(s): 高橋雅英，久新荘一郎
  • Organizer: 第10回CSJ化学フェスタ2020
• [Presentation] 大きな空孔をもつかご形オリゴシランの合成 (2020)
  • Author(s): 高橋雅英，久新荘一郎
  • Organizer: 第24回ケイ素化学協会シンポジウム
• [Presentation] リン原子を含むケイ素クラスターの合成，性質 (2020)
  • Author(s): 円谷朋広，高橋雅英，久新荘一郎
  • Organizer: 日本化学会第100春季年会
• [Presentation] 大きな空孔をもつかご形オリゴシランの合成 (2020)
  • Author(s): 高橋雅英，笠原一紘，久新荘一郎
  • Organizer: 日本化学会第100春季年会
• [Presentation] Silicon Bond: Interaction to Form Micelles in a LC Phase (2019)
  • Author(s): Soichiro Kyushin, Kenji Nanba, Kimio Yoshimura, Yue Zhao, Yasunari Maekawa
  • Organizer: The 7th Asian Silicon Symposium
  • Int'l Joint Research / Invited
• [Presentation] 大きな空孔をもつかご形オリゴシランの合成 (2019)
  • Author(s): 高橋雅英，久新荘一郎
  • Organizer: 第23回ケイ素化学協会シンポジウム
• [Presentation] ケイ素クラスターの電子状態に及ぼすリン原子の効果 (2019)
  • Author(s): 円谷朋広，高橋雅英，久新荘一郎
  • Organizer: 第46回有機典型元素化学討論会
• [Presentation] Silicon Clusters: Synthesis, Structures, and Properties (2018)
  • Author(s): Soichiro Kyushin
  • Organizer: 15th International Symposium on Inorganic Ring Systems
  • Int'l Joint Research / Invited
• [Presentation] ケイ素クラスターの電子状態に及ぼすリン原子の効果 (2018)
  • Author(s): 円谷朋広, 久新荘一郎
  • Organizer: 第8回CSJ化学フェスタ2018
• [Presentation] ケイ素クラスターの電子状態に及ぼすリン原子の効果 (2018)
  • Author(s): 円谷朋広, 久新荘一郎
  • Organizer: 第22回ケイ素化学協会シンポジウム
• [Presentation] Effects of a Phosphorus Atom on Electronic States of Silicon Clusters (2018)
  • Author(s): Tomohiro Tsumuraya, Soichiro Kyushin
  • Organizer: 5th International Symposium of Gunma University Medical Innovation and 9th International Conference on Advanced Micro-Device Engineering
  • Int'l Joint Research