サイクロペンタヌレーションポリメリゼーションによる結合した梯子ポリマー
Sambasiva R Bheemireddy1, Matthew P Hautzinger1, Tao Li2
1Department of Chemistry and Biochemistry and the Materials Technology Center, Southern Illinois University , Carbondale, Illinois 62901, United States.
Journal of the American Chemical Society
|April 4, 2017
まとめ
研究者らは,パラジウム触媒を用いて,新しい梯子ポリマーを合成しました. これらのサイクロペンタフューズされたポリサイクル芳香炭化水素ポリマーは,有機電子に適したユニークな電子特性を有しています.
科学分野:
- 材料科学
- ポリマー化学
- オーガニック電子
背景:
- ポリサイクルアロマティック炭化水素 (PAH) は,有機電子機器において極めて重要です.
- パーソナライズされた電子特性を持つ新しいPAHの開発は,活発な研究分野です.
- 階段ポリマーは,強化された硬さと電子結合を提供します.
研究 の 目的:
- サイクロペンタフューズドPAHを埋め込んだ新合成経路を開発する.
- 調節可能な電子特性を持つドナー-受容体型の共ポリマーを作成します.
- オーガニック・フィールド・エフェクト・トランジスタ (OFET) でこれらのポリマーの可能性を調査する.
主な方法:
- 9,10-ジブロムアントラセンのパラジアム触媒サイクロペンタヌレーションポリメリゼーションと様々なビス・アリレチニル・アレン.
- ベンゼン,チオフェン,またはチオノ[3,2-b]チオフェン単位によるドナー-受容体共ポリマーの合成.
- 鉄塩化物 (FeCl3) を用いたサイクロデヒドロジネーションにより,硬い梯子構造が形成される.
- NMRスペクトロスコーピー (同位体で標識されたポリマーの13C NMRを含む) とUV-Visスペクトロスコーピーを用いた特徴付け.
主要な成果:
- 分子重量 (Mn) が 9~22 kDa のドナー-受容体共ポリマーの成功合成
- サイクロデヒドロジネーションによる硬いレッダーポリマーの形成
- 階段ポリマーは,広いUV-Vis吸収と狭い光帯のギャップ (1.17-1.29 eV) を表した.
- 合成されたポリマーは,有機フィールド効果トランジスタにおけるp型半導体行動を示した.
結論:
- サイクロペンタフューズされたPAHの非伝統的な合成が確立されました.
- 開発されたポリマーは,有機電子アプリケーションのために望ましい光電子特性を持っています.
- 合成戦略は,bis (アリルチニル) アレン単体を選択することによって,ポリマーの構造と特性を調節することを可能にします.
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