Co,O サイトでの C-H アクティベーション: 孤立した表面サイト対分子アナログ
Deven P Estes1, Georges Siddiqi1, Florian Allouche1
1Department of Chemistry and Applied Biosciences, Eidgenössische Technische Hochschule Zürich , CH-8093 Zürich, Switzerland.
Journal of the American Chemical Society
|October 22, 2016
まとめ
シリカのコバルトイオンが炭化水素変換を触媒化する. これらの反応は,コバルト-酸素結合の1,2加法によるC-HまたはH-H結合の異解活性化を含む共通のメカニズムを共有しています.
科学分野:
- 異質な触媒
- 有機金属化学
- 表面科学
背景:
- 炭化水素の活性化と変換は 化学的に重要な課題です
- シリカ表面の移行金属イオンは,触媒として知られています.
- 反応メカニズム,特にC- H活性化については,ほとんど不明です.
研究 の 目的:
- シリコンガラスの上で,はっきりと定義された孤立したCO2イオンを合成する.
- 炭化水素変換反応におけるこれらの場所の触媒的活動を調査する.
- 反応メカニズムの解明には,様々なスペクトロスコピーと運動技術を使用する.
主な方法:
- メタルシロキシド前駆体を使用して,シリカの孤立したCo (II) サイトを合成する.
- プロパン脱水,プロペンの水素化,アルキンのトリメリゼーションのための触媒試験.
- 運動学,運動同位体効果,同位体ラベル付け,パラ水素誘導極化 (PHIP) NMRを含むメカニズム研究.
主要な成果:
- 孤立したCO2サイトは,炭化水素変換反応を効果的に触媒化する.
- デヒドロゲン化,水素化,トリメリゼーションに共通する反応機構が特定された.
- 証拠は,Co-O結合の1,2加法による異解性C-HまたはH-H活性化を支持する.
結論:
- シリカの孤立した Co ((II) サイトは,多用途の触媒である.
- ヘテロリティック活性化を含む提案されたメカニズムは,炭化水素変換の洞察を提供します.
- この研究は,新種のシリカ系触媒の設計の基礎となる.
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