エポキシドのC-O結合割れのためのシリカを支えるオルガノランタン触媒
Zhuoran Wang1,2, Smita Patnaik1,2, Naresh Eedugurala1,2
1Ames Laboratory , U.S. Department of Energy , Ames , Iowa 50011 , United States.
Journal of the American Chemical Society
|January 14, 2020
まとめ
シリカナノ粒子の上でサポートされたオルゴランタン触媒は,エポキシード水酸化を効率的に触媒化する. これらの再利用可能な単一サイト触媒は,選択性と活性性を高め,製品の浄化を簡素化します.
科学分野:
- 有機金属化学
- カタリシス
- 材料科学
背景:
- 有機変換のための効率的で再利用可能な触媒システムの開発は極めて重要です.
- オルガノランタン複合体は独特の反応性を持っていますが,しばしば安定性と分離の問題があります.
- メソポラスシリカナノ粒子 (MSN) は,触媒の固定化のための多用途のプラットフォームを提供します.
研究 の 目的:
- メソポラスシリカナノ粒子 (MSN) に支えられた単位のオルゴランタン複合体を合成し,特徴づけること.
- 環開きエポキシドの水酸化におけるこれらの支援された触媒の触媒活性と選択性を調査する.
- 安定性,再利用性,製品分離の利点を同質な類型と比較して評価する.
主な方法:
- La{C{SiHMe2) 3}3複合体の合成と,700°Cで処理されたSBA型MSN (MSN700) への移植.
- 固体NMR (SSNMR),拡散反射率IRを用いた特徴化と,表面種の構造を決定するための元素分析.
- ピナコルボラン (HBpin) による環開きエポキシドの水酸化におけるサポートされた触媒の触媒試験,その後に反応中間物質のSSNMR分析を行う.
主要な成果:
- MSN700で,主に単足のSiO-La{C(SiHMe2) 3}2の表面結合ランタン複合体を成功裏に合成し,特徴づけました.
- 支持された触媒は,同質的なランタン複合体と比較して,より高い選択性と,ほとんどの場合,より高い活性を示した.
- 触媒は洗浄に優れた耐性を示し,製品の浄化と少なくとも5つの成功したリサイクルを可能にしました.
結論:
- MSNでサポートされている単一サイトオルゴランタン触媒は,エポキシード水酸化に非常に有効です.
- 支援されている触媒は,活性,選択性,再利用性,分離の容易さという点で大きな利点があります.
- この研究は,ランタニド複合体に基づく高度な異質な触媒を開発するための堅実な戦略を示しています.
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