Controlled synthesis of double-helical coordination polymers through self orgainzation of ligand organic units

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K13957
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Inorganic chemistry
• Research Institution: Hokkaido University
• Principal Investigator: Konishi Katsuaki 北海道大学, 地球環境科学研究院, 教授 (80234798)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 配位高分子 / らせん構造 / 金 / 発光

Outline of Final Research Achievements

Gold(I)-thiolate coordination polymers have attracted continuing interests in relation to the applications for pharmaceuticals and their photoluminescence activities. In this research, we studied the synthesis and optical properties of soluble gold(I)-thiolate coordination polymer by using polyethylene glycol (PEG)-modified alkanethiols, and show that the superstructure formation of the polymer chains leads to the appearance of intense photoluminescence due to the interchain aurophilic interaction. When the thiol possesses a long alkyl chain between the terminal PEG and S atom, the AuSR species generated at the initial stage were photoluminescence inactive, but became photoluminescent after being annealed in water. In contrast, Such PL evolution was not observed when the alkyl spacer was swapped with shorter ones, implying the critical roles of the alkyl packing interactions in the controlled formation of superstructure held by aurophilic interactions.

Free Research Field

配位化学

Academic Significance and Societal Importance of the Research Achievements

直鎖状の金チオラート配位高分子は薬剤や発光材料との関連で関心が持たれている。本研究で配位子の有機ユニットの自己組織構造形成を基軸とするアプローチを展開したところ、ポリエチレングリコール鎖を導入して水や各種有機溶媒への親和性を向上させた種々の長鎖アルカンチオラートを用いた場合に、高分子鎖間での金原子間相互作用に由来する強い発光が観察され、二重ラセン構造のような複数の高分子鎖が集合した高次構造が溶液中で形成されることを見出した。また本研究によって有機配位子の設計で直鎖配位高分子のサイズ、高次構造が制御できることを示すことが明らかにされ、今後の機能物質設計に有用な情報が得られた。