Investigations on Synthesis and Properties of as-Indacene and its Congeners

• Project/Area Number: 15K13643
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Organic chemistry
• Research Institution: Osaka University
• Principal Investigator: Tobe Yoshito 大阪大学, 基礎工学研究科, 教授 (60127264)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2016: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2015: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: 開殻性一重項分子 / ジラジカル / 反芳香族性 / インダセン

Outline of Final Research Achievements

(1) As a model study for the synthesis of as-indacene derivatives, an entirely new synthetic route to s-indacene derivatives was successfully developed.t Because this method is applicable to the synthesis of as-indacene derivatives, it has became feasible to achieve the synthesis of the final target.
(2) In order to synthesize as-indacenes fused by thiophene rings, an o-quinodimethane type isomer was successfully generated, giving a dimer derived by 4+4 cycloaddition of the reactive intermediate. Attempts to kinetically stabilize the system by introducing bulky substituents failed to isolate the desired product, indicating the limit of kinetic stability of this system. In addition, two dihydro-o-quinodimethane type derivatives were synthesized and their photophysical properties were investigated.

Research Products

• [Journal Article] Fluoreno[2,3-b]fluorene vs Indeno[2,1-b]fluorene: Unusual Relationship between the Number of π Electrons and Excitation Energy in m-Quinodimethane-Type Singlet Diradicaloids (2017)
  • Author(s): Hirokazu Miyoshi, Masahito Miki, Shintaro Hirano, Akihiro Shimizu, Ryohei Kishi, Kotaro Fukuda, Daisuke Shiomi, Kazunobu Sato, Takeji Takui, Ichiro Hisaki, Masayoshi Nakano, Yoshito Tobe
  • Journal Title: J. Org. Chem. Volume: 82 Issue: 3 Pages: 1380-1388
  • DOI: 10.1021/acs.joc.6b02500
  • Peer Reviewed
• [Presentation] 新奇な電子状態をもつ開殻性一重項分子の合成、構造と物性 (2017)
  • Author(s): 戸部義人
  • Organizer: 新学術領域研究「高次複合光応答分子システムの開拓と学理の構築」第5回公開シンポジウム
  • Place of Presentation: 大阪大学基礎工学国際棟（豊中市・大阪府）
  • Year and Date: 2017-01-20
  • Invited
• [Presentation] Indenofluorene Motifs in Singlet Diradicaloids and Tetraradicaloids (2016)
  • Author(s): Yoshito Tobe
  • Organizer: The 70th Fujiwara Seminar
  • Place of Presentation: THE LUIGANS Spa & Resort（福岡県・福岡市）
  • Year and Date: 2016-04-17
  • Invited
• [Remarks] 大阪大学大学院基礎工学研究科・物質創成専攻・未来物質領域・新物質創成講座・機能分子創製グループ
  • URL: http://www.supra.chem.es.osaka-u.ac.jp/publications/
• [Remarks] 大阪大学大学院基礎工学研究科・物質創成専攻・未来物質領域・新物質創製講座・機能分子創製グループ
  • URL: http://www.supra.chem.es.osaka-u.ac.jp/publications/