巨大分子デンドリマーの合成と光機能界面への展開

• Project/Area Number: 17029010
• Research Category: Grant-in-Aid for Scientific Research on Priority Areas
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: University of Tsukuba
• Principal Investigator: 新井 達郎 筑波大学, 大学院数理物質科学研究科, 教授 (50151139)
• Project Period (FY): 2005 – 2006
• Project Status: Completed (Fiscal Year 2006)
• Budget Amount: ¥4,800,000 (Direct Cost: ¥4,800,000); Fiscal Year 2006: ¥2,400,000 (Direct Cost: ¥2,400,000); Fiscal Year 2005: ¥2,400,000 (Direct Cost: ¥2,400,000)
• Keywords: 巨大分子 / 光化学 / 光異性化 / デンドマリー / 励起状態 / 蛍光 / スチルベン / 構造変化 / 光物理 / ダイナミクス / デンドリマー

Research Abstract

巨大分子の光化学は、視覚における光情報の捕集と伝達の観点から興味深い。このような観点から、光応答性巨大分子デンドリマーを合成し、光機能界面としての可能性も含めて検討した。
励起-重項状態で100ps程度の時間で構造変化しうるスチルベン骨格を用いたデンドリマーを合成し、周辺の巨大な置換基が反応ダイナミクスや物性に及ぼす効果を研究した。特にスチルベンのベンゼン環の異なる置換位置に巨大置換基として世代の異なるデンドロンを置換したデンドリマーのスチルベン部位の超高速光反応と周辺部位も含めた分子全体のゆっくりした構造変化について、蛍光や反応の効率、反応の方向などを中心に各種分光学的手法も含めて検討した。
研究した中でも、疎水部として蛍光性かつ光応答性の部位を導入し、外側に親水基を導入して水溶性となった分子では、内部の疎水部の特異な光機能性がいくつか観測された。例えば、水溶性スチルベンデンドリマーの水中での高速光反応ダイナミクスに関した研究では、分子中心と周辺の構造変化の特徴や新規な異性化機構の可能性を提案した。スチルベン骨格を中心部に有するデンドリマーでは、トランス体は紫色の蛍光を発するが、光異性化により生成したシス体は、蛍光を発しなくなる。油水界面の効果で光反応が特異的な方向にのみ進行すること、中心の二重結合の異性化を巨大分子全体の構造変化として増幅できる可能性、水中に存在する有機巨大分子を蛍光性から無蛍光性に完全に変化可能であるなど水溶性の巨大分子の光による構造変化を新しい機能に展開可能な成果を得た。さらに、これらの光反応性が、デンドロン置換基の置換位置の効果を受けること、水溶性デンドリマーの内部に対する機能分子の取り込みと放出を光で制御できる可能性についても見いだした。

Research Products

• [Journal Article] The Effect of meta-Substitution on the Photochemical Properties of Benzoxazole Derivatives (2007)
  • Author(s): Ohshima, Asuka
  • Journal Title: Bulletin of the Chemical Society of Japan 80 Pages: 561-566
• [Journal Article] Photoisomerization and Fluorescence Properties of para-Substituted Benzyl Ether-Type Stilbene Dendrimers (2007)
  • Author(s): Watanabe, Shinko
  • Journal Title: Bulletin of the Chemical Society of Japan 80 Pages: 586-588
• [Journal Article] The first observation of the effect of dendritic structure to produce the triplet excited state of the core stilbene by dendron excitation (2007)
  • Author(s): Miura, Yousuke
  • Journal Title: Tetrahedron Letters 48 Pages: 639-641
• [Journal Article] The relaxation dynamics of the excited state of stilbene dendrimers substituted with phenylacetylene groups (2006)
  • Author(s): Nishimura, Yoshinobu
  • Journal Title: Journal of Photochemistry and Photobiology A : Chemistry 178 Pages: 150-155
• [Journal Article] Volume-Demanding Cis-Trans Isomerization of 1,2-Diaryl Olefins in the Solid State (2006)
  • Author(s): Natarajan, Arunkumar
  • Journal Title: Journal of Organic Chemistry 71 Pages: 1055-1059
• [Journal Article] The Spin Mixing Process of a Radical Pair in Low Magnetic Field Observed by Transient Absorption Detected Nanosecond Pulsed Magnetic Field Effect (2006)
  • Author(s): Miura, Tomoaki
  • Journal Title: Journal of Physical Chemistry A 110 Pages: 4151-4156
• [Journal Article] Synthesis and Photochemical Properties of a New Water-soluble Coumarin, Designed as a Chromophore for Highly Water-Soluble and Photolabile Protecting Group (2006)
  • Author(s): Senda, Naoko
  • Journal Title: Bulletin of the Chemical Society of Japan 79 Pages: 1753-1757
• [Journal Article] Solvent Effect on the Photochemical Properties of Symmetrically Substituted trans-3, 3', 5, 5' -Tetramethoxystilbene (2006)
  • Author(s): Hayakawa, Junpei
  • Journal Title: Journal of Physical Chemistry A 110 Pages: 12566-12571
• [Journal Article] A practical simulation and a novel insight to the magnetic field effect on a radical pair in a micelle (2006)
  • Author(s): Maeda, Kiminori
  • Journal Title: Molecular Physics 104 Pages: 1779-1788
• [Journal Article] Stereoselective Synthesis of cis- and trans-Oligo(phenylenevinylene)s via Palladium-Catalyzed Cross-Coupling Reactions (2006)
  • Author(s): Katayama, Hiroyuki
  • Journal Title: Journal of Organic Chemistry 71 Pages: 2699-2705
• [Journal Article] Exciplex Formation of Intermolecularly Hydrogen-Bonded System between Anthracene and N,N^Dimethylaniline Derivatives (2006)
  • Author(s): Ohshiro, Ikuma
  • Journal Title: Bulletin of the Chemical Society of Japan 79 Pages: 1950-1954
• [Journal Article] Substituent Effects on the Ground-State Properties of Naphthalene-Based Analogues of Salicylideneaniline in Solution (2006)
  • Author(s): Ohshima, Asuka
  • Journal Title: Bulletin of the Chemical Society of Japan 79(2) Pages: 305-311
• [Journal Article] Photochemical and complexation studies for new fluorescent and colored chelator (2005)
  • Author(s): Ohshima, Asuka
  • Journal Title: Science and Technology of Advanced Materials 6(6) Pages: 633-643
• [Journal Article] Spin Dynamics of the Radical Pair in a Low Magnetic Field Studied by the Transient Absorption Detected Magnetic Field Effect on the Reaction Yield and Switched External Magnetic Field (2005)
  • Author(s): Suzuki, Toshiaki
  • Journal Title: Journal of Physical Chemistry A 109(44) Pages: 9911-9918
• [Journal Article] Enhancement of the Large Stokes-Shifted Fluorescence Emission from the 2-(2'-Hydroxyphenyl)benzoxazole Core in a Dendrimer (2005)
  • Author(s): Ohshima, Asuka
  • Journal Title: Journal of Physical Chemistry A 109(43) Pages: 9731-9736
• [Journal Article] Photochemistry of salicylideneaniline analogue at low temperature. (2005)
  • Author(s): Ohshima, Asuka
  • Journal Title: Chemistry Letters 34(9) Pages: 1288-1289
• [Journal Article] Effect of the intramolecular hydrogen bonding on the photochromic properties of the hemiindigo dye having a pyrrole ring. (2005)
  • Author(s): Ikegami, Masash
  • Journal Title: Molecular Crystals and Liquid Crystals 431 Pages: 445-449
• [Journal Article] Photoisomerization and photoinduced hydrogen-atom transfer in 1-chloro-4-(2-pyrrol-2-ylethenyl)phthalazine. (2005)
  • Author(s): Akiu, Kei
  • Journal Title: Bulletin of the Chemical Society of Japan 78(6) Pages: 1132-1137
• [Journal Article] Dynamics of Intramolecular Electron Transfer Reaction of FAD Studied by Magnetic Field Effects on Transient Absorption Spectra (2005)
  • Author(s): Murakami, Masaaki
  • Journal Title: Journal of Physical Chemistry A 109(26) Pages: 5793-5800
• [Journal Article] Study on oxygen quenching processes of the excited state dendrimer molecules (2005)
  • Author(s): Momotake, Atsuya
  • Journal Title: Chemistry Letters 34(5) Pages: 684-685
• [Journal Article] Recognition of substituted cytosine derivatives by the base pairing with guanine connected to pyrene. (2005)
  • Author(s): Kawai, Takahiro
  • Journal Title: Chemical Physics Letters 407(1-3) Pages: 58-62
• [Journal Article] Photochromic and fluorescence properties of a hemiindigo in the presence of bovine serum albumin. (2005)
  • Author(s): Ikegami, Masashi
  • Journal Title: Chemistry Letters 34(4) Pages: 492-493
• [Journal Article] The photochemical isomerization of cross-linked 1,3,5-tristyryl benzene dendrimer with hula-twist mechanism. (2005)
  • Author(s): Uda, Mayuko
  • Journal Title: Tetrahedron Letters 46(17) Pages: 3021-3024
• [Book] 新規クロミック材科の設計・機能・応用 (2005)
  • Author(s): Momotake, Atsuya
  • Total Pages: 15
  • Publisher: 株式会社シーエムシー出版