オーガノメタリック Cu20ナノクラスター:シリカの合成,特徴化,固定化,および"クリック"化学
Andrew W Cook1, Zachary R Jones2, Guang Wu1
1Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106, United States.
Journal of the American Chemical Society
|December 7, 2017
まとめ
原子精度の高いナノクラスター (APNC) は新しい触媒的可能性を提供します. この研究では,室温で前処理なしに"クリック"反応を効果的に触媒化し,サポートされたときに安定性を高める新しい銅APNCを導入しました.
科学分野:
- ナノ科学とナノテクノロジー
- 有機金属化学
- カタリシス
背景:
- オーガノメタリックリガンドで保護された原子精度の高いナノクラスター (APNC) は,ナノ科学の有望な分野である.
- これらのAPNCは,焼却などの苛酷な活性化方法を避けることが期待されています.
研究 の 目的:
- 新型混合金属製銅APNCを合成する
- 特に"クリック"反応について,その触媒的活動を調査する.
- 合成されたAPNCの安定性と不動性を調べるため
主な方法:
- 銅APNC [Cu20 ((CCPh) 12 ((OAc) 6) ] (1) の合成は,フェニラセチレンの存在下でCu ((OAc) をPh2SiH2で還元する.
- クラスタを部分的に脱水したシリカに固定する.
- Cu K-エッジ EXAFSスペクトロスコーピーを用いた特徴付け.
- [3+2]サイクル添加反応における触媒活性の評価
主要な成果:
- 独特の四面体 [Cu4]2+コアを特徴とする混合有金属銅APNC [Cu20(CCPh) 12 ((OAc) 6] (1) の合成に成功した.
- クラスターはシリカで固定され,フェニラセチレンを放出します.
- サポートされていないクラスターとサポートされたクラスターは,前処理なしに室温で"クリック"反応のための効果的な触媒です.
- EXAFSの分析は,サポートされていないクラスターとサポートされているクラスターの構造的類似性を確認し,高安定性を示す,触媒化後の重要な変化を明らかにしなかった.
結論:
- 新しい,安定した銅のAPNCが合成され,特徴づけられました.
- APNCは"クリック"反応のための効果的な,前処理フリーな触媒です.
- 不動化は反応条件下でのクラスターの安定性を高め,実用的な応用への道を開きます.
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