Syntheses, Electronic Structures, and Intermolecular Interactions of Singlet Biradical Molecules

• Project/Area Number: 17550034
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Organic chemistry
• Research Institution: Osaka Univeristy
• Principal Investigator: KUBO Takashi Osaka Univeristy, Graduate School of Science, Professor, 理学研究科, 教授 (60324745)
• Project Period (FY): 2005 – 2006
• Project Status: Completed (Fiscal Year 2006)
• Budget Amount: ¥3,600,000 (Direct Cost: ¥3,600,000); Fiscal Year 2006: ¥1,400,000 (Direct Cost: ¥1,400,000); Fiscal Year 2005: ¥2,200,000 (Direct Cost: ¥2,200,000)
• Keywords: Singlet biradical / Phenalenyl / Intermolecular interaction / Electro-conductivity / Non-linear optics / Two photon absorption / Polarized reflection spectra / SQUID

Research Abstract

Some Kekule compounds such as quinoid hydrocarbons have relatively small HOMO-LUMO gaps and show extremely high chemical reactivity. The representative is p-quinodimethane that has been defined as a biradicaloid compound, which could be categorized as a delocalized singlet biradical. In order to isolate such a reactive closed-shell biradical and to investigate properties associated with the biradical character, we introduced spin-delocalization moieties to p-quinodimethane and 2,6-naphthoquinodimethane. Newly designed molecules were prepared by multistep syntheses, and were found to be stable even in air at room temperature. Biradical character of the compounds was estimated to be 30% and 50% by a CASSCF(2,2)/6-31G calculation, respectively. An X-ray crystallographic analysis revealed one-dimensional π-stacking chains with short π-π contacts (3.14-3.16 Å). Compressed pellets of the compounds exhibited semi-conductive behavior (σ_<RT>=〜10^<-5> S cm^<-1>1,E_a = 0.2-0.3 eV), and large bandwidths were achieved along the π-π stacking according to an EHMO band calculation. Polarized reflection spectra of the single crystals showed intense bands at near-IR regions in the π-π stacking directions. The solid state bands are extraordinary lower in energy than the solution absorption bands. A strong intermolecular spin-spin interaction as well as an intramolecular one would be responsible for the large bandwidths and the lower-energy shifts of the absorption bands.

Research Products

• [Journal Article] Theoretical Study on the Second Hyperpolarizabilities of Phenalenyl Radical Systems Involving Acetylene and Vinylene Linkers : Diradical Character and Spin Multiplicity Dependences (2007)
  • Author(s): Suguru Ohta, et al.
  • Journal Title: Journal of Physical Chemistry A. 118 Pages: 3633-3641
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Strong Two-Photon Absorption of Singlet Diradical Hydrocarbons (2007)
  • Author(s): Kenji Kamada, et al.
  • Journal Title: Angewandte Chemie International Edition 46 Pages: 3544-3546
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Singlet Biradical Character of Phenalenyl-based Kekule Hydrocarbon with Naphthoquinoid Structure (2007)
  • Author(s): Takashi Kubo, et al.
  • Journal Title: Organic Letters 9 Pages: 81-84
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Syntheses and Unusual Segregated-Alternated Hybrid Stacking Structure of Hydrogen-Bonded Charge- Transfer Complexes Composed of Bis[2,3-pyridinedithiolate] Metal Complexes (2007)
  • Author(s): Sota Shibahara, et al.
  • Journal Title: Inorganic Chemistry 46 Pages: 1162-1170
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Theoretical Study on the Second Hyperpolarizabilities of Phenalenyl Radical Systems Involving Acetylene and Vinylene Linkers : Diradical Character and Spin Multiplicity Dependences (2007)
  • Author(s): Suguru Ohta, et al.
  • Journal Title: J.Phys.Chem.A. 111 Pages: 3633-3641
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Strong Two-Photon Absorption of Singlet Diradical Hydrocarbons (2007)
  • Author(s): Kenji Kamada, et al.
  • Journal Title: Angew.Chem.Int.Ed. 46 Pages: 3544-3546
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Singlet Biradical Character of Phenalenyl-based Kekule Hydrocarbon with Naphthoquinoid Structure (2007)
  • Author(s): Takashi Kubo, et al.
  • Journal Title: Org.Lett. 9 Pages: 81-84
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Syntheses and Unusual Segregated-Alternated Hybrid Stacking Structure of Hydrogen-Bonded Charge-Transfer Complexes Composed of Bis[2,3-pyridinedithiolate]Metal Complexes (2007)
  • Author(s): Sota Shibahara, et al.
  • Journal Title: Inorg.Chem. 46 Pages: 1162-1170
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Singlet Biradical Character of Phenalenyl-based Kekule Hydrocarbon with Naphthoquinoid Structure (2007)
  • Author(s): KUBO Takashi
  • Journal Title: Organic Letters 9巻 Pages: 81-84
• [Journal Article] Syntheses and Unusual Segregated-Alternated Hybrid Stacking Structure of Hydrogen-Bonded Charge- Transfer Complexes Composed of Bis[2,3-pyridinedithiolate]Metal Complexes (2007)
  • Author(s): SHIBAHARA Sota
  • Journal Title: Inorganic Chemistry 46巻 Pages: 1162-1170
• [Journal Article] Second hyperpolarizabilities of polycyclic diphenalenyl radicals : Effects of paralortho-quinoid structures and central ring modification (2006)
  • Author(s): Masayoshi Nakano, et al.
  • Journal Title: Chemical Physics Letters 429 Pages: 174-179
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Bis(9-phenanthryl)ethyne (2006)
  • Author(s): Takashi Kubo, et al.
  • Journal Title: Acta Crystallographica E62
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Origin of the enhancement of the second hyperpolarizability of singlet diradical systems with intermediate diradical character (2006)
  • Author(s): Masayoshi Nakano, et al.
  • Journal Title: Journal of Chemical Physics 125
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Powder XRD and Solid-State ^2H-NMR Studies of RAP-Protected Palladium Nanoparticle (RAP=Rubeanic Acid Polymer) (2006)
  • Author(s): Musashi Fujishima, et al.
  • Journal Title: Solid State Phenomena 111 Pages: 107-110
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] Second hyperpolarizabilities of polycyclic diphenalenyl radicals : Effects of para/ortho-quinoid structures and central ring modification (2006)
  • Author(s): Masayoshi Nakano, et al.
  • Journal Title: Chem.Phys.Lett. 429 Pages: 174-179
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Origin of the enhancement of the second hyperpolarizability of singlet diradical systems with intermediate diradical character (2006)
  • Author(s): Masayoshi Nakano, et al.
  • Journal Title: J.Chem.Phys 125
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] Bis(9-phenanthryl)ethyne (2006)
  • Author(s): KUBO Takashi
  • Journal Title: Acta Crystallographica E62巻
• [Journal Article] Origin of the enhancement of the second hyperpolarizability of singlet diradical systems with intermediate diradical character (2006)
  • Author(s): NAKANO Masayoshi
  • Journal Title: Journal of Chemical Physics 126巻
• [Journal Article] Second hyperpolarizabilities of polycyclic diphenalenyl radicals : Effects of paralortho-quinoid structures and central ring modification (2006)
  • Author(s): NAKANO Masayoshi
  • Journal Title: Chemical Physics Letters 429巻 Pages: 174-179
• [Journal Article] Powder XRD and Solid-State 2H-NMR Studies of RAP-Protected Palladium Nanoparticle (RAP=Rubeanic Acid Polymer) (2006)
  • Author(s): FUJISHIMA Musashi
  • Journal Title: Solid State Phenomena 111巻 Pages: 107-110
• [Journal Article] Second hyperpolarizability of phenalenyl radical system involving acetylene o-conjugated bridge (2006)
  • Author(s): Ohta, S., Nakano, M., Kubo, T., Kamada, K., Ohta, K., Kishi, R., Nakagawa, N., Champagne, B., Botek, E., Umezaki, S., Takebe, A., Takahashi, H., Furukawa, S., Morita, Y., Nakasuji, K., Yamaguchi, K.
  • Journal Title: Chemical Physics Letters 418巻(in press)
• [Journal Article] Second hyperpolarizabilities of polycyclic aromatic hydrocarbons involving phenalenyl radical units (2006)
  • Author(s): Nakano, M., Kubo, T., Kamada, K., Ohta, K., Kishi, R., Ohta, S., Nakagawa, N., Takahashi, H., Furukawa, S., Morita, Y., Nakasuji, K., Yamaguchi, K.
  • Journal Title: Chemical Physics Letters 418巻 Pages: 142-147
• [Journal Article] Synthesis, Intermolecular Interaction, and Semi-conductive Behavior of a Delocalized Singlet Biradical Hydrocarbon (2005)
  • Author(s): Kubo, T., Shimizu, A., Sakamoto, M., Uruichi, M., Yakushi, K., Nakano, M., Shiomi, D., Sato, K., Takui, T., Morita, Y., Nakasuji, K
  • Journal Title: Angewandte Chemie International Edition 44巻 Pages: 6564-6568
• [Journal Article] Molecular structure and properties of bis (o-diiminobenzosemiquinonato) metal (II) complexes monocation in salts and charge transfer complexes (2005)
  • Author(s): Kubo, T., Sakamoto, M., Kitagawa, H., Nakasuji K.
  • Journal Title: Synthetic Metals 153巻 Pages: 465-468
• [Journal Article] Magnetic interaction in 2D sheet structure of bis (1H, 4H-5,6-diethylpyrazinedithiolato) copper (II) trifluoroacetate (2005)
  • Author(s): Kubo, T., Ohashi, M., Kitagawa, H., Nakasuji K.
  • Journal Title: Polyhedron 24巻 Pages: 2528-2532
• [Journal Article] Biradicaloid character of phenalenyl-based aromatic compounds with a small HOMO-LUMO gap (2005)
  • Author(s): Kubo, T., Sakamoto, M., Nakasuji K.
  • Journal Title: Polyhedron 24巻 Pages: 2522-2527
• [Journal Article] Preparation and proton transport property of N,N'-diethyldithiooxamidatocopper coordination polymer (2005)
  • Author(s): Nagao, Y., Kubo, T., Nakasuji, K., Ikeda, R., Kojima, T., Kitagawa, H.
  • Journal Title: Synthetic Metals 154巻 Pages: 89-92
• [Journal Article] Second Hyperpolarizability (y) of Singlet Diradical System ; Dependence of y on the Diradical Character (2005)
  • Author(s): Nakano, M., Kishi, R., Nitta, T., Kubo, T., Nakasuji, N., Kamada, K., Ohta, K., Champagne, B., Botek, E., Yamaguchi K.
  • Journal Title: Journal of Physical Chemistry A 109巻 Pages: 885-891
• [Journal Article] A New Hydrogen-Bonded Charge-Transfer Complex [Ni(Hpydt)_2-TNAP; Synthesis, Structure and Electrical Conductivity.
  • Author(s): Sota Shibahara, et al.
  • Journal Title: Inorganic Chemical Communication 印刷中
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] CASCI-DFT study of the phenalenyl radical system.
  • Author(s): Takeshi Ukai, et al.
  • Journal Title: Polyhedron 印刷中
  • Description: 「研究成果報告書概要(和文)」より
• [Journal Article] A New Hydrogen-Bonded Charge-Transfer Complex [Ni(Hpydt)_2]-TNAP ; Synthesis, Structure and Electrical Conductivity
  • Author(s): Sota Shibahara, et al.
  • Journal Title: Inorg.Chem.Comm. (in press)
  • Description: 「研究成果報告書概要(欧文)」より
• [Journal Article] CASCI-DFT study of the phenalenyl radical system
  • Author(s): Takeshi Ukai, et al.
  • Journal Title: Polyhedron (in press)
  • Description: 「研究成果報告書概要(欧文)」より
• [Book] 大学院講義有機化学(演習編) (2007)
  • Author(s): 野依良治 他 編
  • Total Pages: 176
  • Publisher: 東京化学同人
  • Description: 「研究成果報告書概要(和文)」より
• [Patent(Industrial Property Rights)] 二光子吸収材料 (2005)
  • Inventor(s): 中野雅由, 久保孝史, 鎌田賢司, 大田浩二, 山口 兆, 中筋一弘, 森田 靖, 岸 亮平, 清水章弘
  • Industrial Property Rights Holder: 大阪大学及び, 独立行政法人産業技術総合研究所
  • Filing Date: 2005-09-15
  • Description: 「研究成果報告書概要(和文)」より
• [Patent(Industrial Property Rights)] 二光子吸収材料 (2005)
  • Inventor(s): 中野雅由, 久保孝史, 鎌田賢司, 大田浩二, 山口 兆, 中筋一弘, 森田 靖, 岸 亮平, 清水章弘
  • Industrial Property Rights Holder: 大阪大学及び独立行政法人産業技術総合研究所
  • Industrial Property Number: 2005-267913
  • Filing Date: 2005-09-15