β,β-直接結合したポルフィリン環:合成,光物理特性,フルレンの結合
Qiang Chen1, Amber L Thompson1, Kirsten E Christensen1
1Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K.
Journal of the American Chemical Society
|May 18, 2023
まとめ
独特の3D構造を持つ新型の循環性亜鉛ポルフィリンオリゴーマー (CP3およびCP4) を合成した. これらのポルフィリンには独特の光物理的特性があり,CP4はディトピックフルレンの受容体として作用する.
科学分野:
- 超分子化学
- 有機化学
- 材料科学
背景:
- サイクリック・ポルフィリン・オリゴマーは,光合成光採集システムと超分子受容体のモデルとして機能する.
- 循環性ポルフィリンにおける直接のβ,β結合は合成的に困難であり,十分に研究されていない.
研究 の 目的:
- 前例のないβ,βと直接結合した周期性亜鉛ポルフィリントリマー (CP3) とテトラマー (CP4) を合成する.
- これらの新種のオリゴマーの3次元構造,光物理的特性,および超分子受容体の能力を調査する.
主な方法:
- ヤマモトカップリングの2,3-ジブロモポルフィリン前駆体
- NMRスペクトロスコーピー,質量スペクトロメトリー,単結晶X線微分を用いた構造的特徴づけ.
- 密度関数理論 (DFT) を用いた計算モデリングによる幾何学最適化.
- 光物理学的および電気化学的性質の測定
- NMR タイトリングとX線微分を用いたフルレンの結合試験.
主要な成果:
- CP3とCP4の周期性亜鉛ポルフィリンオリゴマーの合成に成功した.
- プロペラ (CP3) とセール (CP4) の3D構造の決定
- CP3は,二面角が小さいため,CP4と比較してより強いπ結合と赤偏移吸収を示す.
- CP3の中央環は部分的に芳香性 (HOMA 0. 52) であり,CP4の中央環は芳香性ではない (HOMA - 0. 02).
- CP4は,C70とC60に対する有意な結合親和性を持つディトピーフルレン受容体の活性を示している.
結論:
- β,β-直接結合は,調節可能な性質を持つ新しい循環型ポルフィリン構造の形成を可能にします.
- 幾何学的差異は電子構造,π結合,および芳香性に大きく影響する.
- の形状のCP4はフルレンの効果的なディトピック受容体であり,分子認識と自己組み立てにおける潜在的な応用を強調しています.
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