Development of dynamic covalent radicals for molecular self organization

2020 Fiscal Year Final Research Report

• Project/Area Number: 17H04874
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Functional solid state chemistry
• Research Institution: Osaka Prefecture University (2018-2020); Kyoto University (2017)
• Principal Investigator: Sakamaki Daisuke 大阪府立大学, 理学(系)研究科(研究院), 助教 (60722741)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 有機ラジカル / 動的共有結合 / 芳香族アミン / 自己組織化 / サーモクロミズム

Outline of Final Research Achievements

we demonstrate that the dimerization behavior of amine-substituted dicyanomethyl radicals can be switched from s- to pi-dimerization simply by varying the
electron-donating substituents. The dicyanomethyl radical with the julolidine skeleton does not undergo sigma-dimerization and was isolated as a stable radical in spite of the absence of bulky protecting groups. X-ray single-crystal analysis revealed that this radical forms the pi-dimer in the crystalline state, and variable temperature spectroscopy showed that this radical is in equilibrium
with the p-dimer in toluene solution. DFT calculations point to the importance of electrostatic interactions as a driving force for the pi-dimerization of this radical because of its polarized structure.

Free Research Field

構造有機化学

Academic Significance and Societal Importance of the Research Achievements

本研究によって、共有結合の断片であるラジカルがどのように二量化するかをコントロールするための分子設計指針を得ることが出来た。本研究で得られた知見は、有機ラジカルを分子の自己組織化や、外部刺激に応答して性質が変化する機能性材料などへと応用するための有効な指針となると考えられる。