毛穴のある結晶における好ましい光反応,金属マクロサイクルフレームワーク:PdII-メディエートされたオレフィン移動 [2+2]サイクル添加
Hirotaka Yonezawa1, Shohei Tashiro1, Takafumi Shiraogawa2
1Department of Chemistry, Graduate School of Science , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku, Tokyo 113-0033 , Japan.
Journal of the American Chemical Society
|November 9, 2018
まとめ
メタルマクロサイクルフレームワーク (MMF) では,1,6-ダイネは典型的な [2+2] サイクル添加ではなく,光誘導によるオレフィン移動を経験する. この狭い空間は反応性を制御し 望ましくない反応を抑制し 選択的変換を可能にします
科学分野:
- 超分子化学
- 写真化学
- カタリシス
背景:
- ナノサイズの狭い空間では 化学反応を正確に制御できます
- 1,6-ディエンは,通常,光照射下で分子内 [2+2] サイクロードダクトを形成する.
- 多孔性物質内の光化学反応の選択性を制御することは大きな課題です.
研究 の 目的:
- メタル・マクロサイクル・フレームワーク (MMF) 内の1,6ダイエンの光化学的振る舞いを調査する.
- MMFの反応経路を変え,選択性を高める能力を実証する.
- 閉じ込められた環境における光誘導によるオレフィン移動のメカニズムを解明する.
主な方法:
- メタル・マクロサイクル・フレームワーク (MMF) の合成と特徴付け
- MMF内の1,6-ディエンの基板による光照射実験
- UV対分散反射スペクトル検査を含むスペクトル解析
- 構造的決定のためのX線 difraktion (XRD)
- 機械的な洞察のためのCASPT2計算による質量スペクトロメトリー.
主要な成果:
- 1,6-ディエンは,MMF内で好ましく光誘導オレフィン移動を経験しました.
- 内分子 [2+2] サイクロアディションは,閉じ込められた空間で完全に抑制されました.
- 光誘導によるPd-Cl結合解離を含む反応機構が提案された.
- オレフィン移動の基板の範囲は,代用されたアルリルベンゼン誘導体で成功裏に試験された.
結論:
- 金属マクロサイクルフレームワークは,光化学反応経路を効果的に制御することができます.
- MMF内の閉じ込めは選択的なオレフィン移動を可能にし,競合するサイクル添加反応を抑制します.
- この研究は,多孔結晶物質における光誘導変換のメカニズム的理解を提供します.
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