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メタルテンプレート/金属交換方法による離散的なMn(II) ビスフェン複合体の共性異質化:強化反応性を持つエポキシダーション触媒
Tracy J Terry1, T Daniel P Stack
1Department of Chemistry, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|March 21, 2008
まとめ
SBA-15シリカの金属模板法を用いたエポキシデーション触媒の不動化により,安定性と選択性が向上する. このテンプレート化されたアプローチは,ランダム・グラフティングまたは同質な触媒と比較して,より良い触媒性能とリサイクルを提供します.
科学分野:
- マテリアルサイエンス 材料科学
- カタリシス カタリシス カタリシス
- ナノテクノロジー ナノテクノロジー
背景:
- 固体基板にエポキシデーション触媒を固定することは,場所の隔離,安定性の向上,再利用の容易さなどの利点を提供します.
- ビス-1,10-フェナントロリンリンガンドは,効率的なエポキシデーション触媒の開発に不可欠です.
研究 の 目的:
- ビス-1,10-フェナントロリンリガンドをメソポラスSBA-15シリカに共振的に結合するための合成金属テンプレート方法を開発する.
- このテンプレートメソッドを使用して固定されたマンガネス触媒のエポキシデーション反応性と性能を評価するために.
主な方法:
- メタルテンプレート/メタル交換戦略を使用して,SBA-15シリカの定義された調整環境を作成しました.
- プリントされたシリカ基板にはマンガンが加えられ,エポキシデーション触媒が形成された.
- 触媒の性能は,オレフィンエポキシデーションをペラセチン酸で用いたランダムに挿入された類似品および均質な触媒と比較した.
主要な成果:
- テンプレートメソッドは,ランダムな移植と比較して,再現しやすい,溶液のようなbis-1,10-フェナントロリン調整を生成しました.
- 印刷されたマンガネス触媒は,エポキシド選択性,より広い基板範囲,より高い反応性を改善しました.
- テンプレート型触媒は,効率的なリサイクルと,同質でランダムに挿入された触媒よりも優れた性能を示し,変数の反応性または分解を示した.
結論:
- SBA-15シリカ上のbis-1,10-phenanthrolineリガンドの金属テンプレート固定化は,高度に活性的で選択的なエポキシデーション触媒を作成するための実行可能な戦略です.
- この方法は,ランダムな移植と均質な触媒の限界を克服し,オレフィンエポキシデーションの安定性,再利用性,効率性を向上させます.
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