配合性有機枠組における正方形の網の絡み合い
Fangying Jin1, Ha L Nguyen1,2, Zhiye Zhong3
1Department of Chemistry, University of California-Berkeley, Kavli Energy Nanoscience Institute at UC Berkeley, and Berkeley Global Science Institute, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|January 24, 2022
まとめ
研究者らは,2D正方形の共性有機フレームワーク (COF) を初めて合成した. この突破は,新しいSFTBビルディングユニットを利用し,π-πの積み重ねを防止し,高度な材料設計のための絡み合いを可能にします.
科学分野:
- 材料科学
- 超分子化学
- 有機化学
背景:
- 協和有機フレームワーク (COF) は,調節可能な特性を有する結晶性多孔ポリマーである.
- 2D COFは通常,複雑なアーキテクチャの形成を阻害する強力な π-π スタッキングを示す.
- COF トポロジーを制御し,集積を防止するための戦略を開発することは,高度なアプリケーションにとって極めて重要です.
研究 の 目的:
- 新しく絡み合った2Dの正方形COF構造を合成する.
- π-πの積み重ねを防止し,絡み合いを可能にするためにSFTBの建築ユニットの役割を調査する.
- 複雑なCOFアーキテクチャを作成するための新しい設計原則を確立します.
主な方法:
- 4,4′,4′-9,9′-スピロビ[フッ素]-2,2′,7,7′-テトライル) -テトラベンザルデヒド (SFTB) とp-フェニレンダイアミン (PPA) またはベンジジン (BZD) を使用して2DCOF,COF-38とCOF-39の合成.
- COF-39の構造を決定する単結晶電子微分分析
- 歪んだ四面体SFTBブロックを使用してフレームワークを制御します.
主要な成果:
- COF-38とCOF-39の合成が成功し,2Dの四角 COF構造の最初の例となった.
- 相互に絡み合った2D正方形網 (sqlトポロジー) を明らかにするCOF-39の構造解明.
- SFTBのビルユニットがπ-πの積み重ねを効果的に防止し,絡み合ったネットワークの形成を容易にすることを実証する.
結論:
- SFTBのビルユニットは,2D COFの π-π スタッキングを克服し,絡み合った構造の形成を可能にする鍵です.
- この研究は,複雑で相互接続されたCOFアーキテクチャの設計のための新しい戦略を導入します.
- この発見は,共性有機フレームワークの理解と設計の原則を大幅に前進させました.
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