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ビス (((イミノ)) ピリジンのコバルト触媒アルケンのイソメリゼーション-ヒドロボレーション:端末選択性の遠隔水素機能化のための戦略

Jennifer V Obligacion¹, Paul J Chirik

¹Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States.

Journal of the American Chemical Society

|December 17, 2013

まとめ

ビスミノピリジンコバルト触媒は,ピナコルボラン (HBPin) を使用してアルケンの水酸化を効率的に実行します. 改変された触媒は,阻害された基板に対して高い活性を示し,C-H結合の機能化のための新しい経路を提供します.

科学分野:

有機金属化学有機金属化学
カタリシスカタリシスカタリシス
オーガニック・シンセシスオーガニック・シンセシス

背景:

アルケンの水酸化は,重要な有機変換である.
効率的で選択的な触媒の開発は,合成化学にとって極めて重要です.

研究の目的:

アルケンの水酸化のための触媒としてのビス・ミノ・ピリジン・コバルト・メチル複合体を調査する.
活性と選択性を向上させるための触媒構造を最適化するために,特にステリカルに阻害された基板を使用します.

主な方法:

ビス・イミノ・ピリジン・コバルト・メチル複合体の合成と特徴付け.
ピナコルボラン (HBPin) を用いて様々なアルケーンを用いた触媒水溶解反応.
最適な構造を特定するために,触媒置換剤のスクリーニング.

主要な成果:

ビス・ミノ・ピリジン・コバルト・メチル複合体は,様々なアルケンの水酸化を効果的に触媒化する.
ピロリジニル置換の触媒は,ステリカルに要求される基板に対して優れた活性を示した.
反応は,穏やかな条件 (23 °C) の下で,高抗マルコヴニコフ選択性で,きれいな基板で進行した.
内部オレフィンは,独占的な末端ボロン添加を経て,遠隔C-H機能化を可能にしました.

結論:

改変されたビス・イミノ・ピリジン・コバルト複合体は,アルケンの水酸化のための非常に効果的な触媒である.
開発された触媒システムは,ヒドロボレーションとC-H機能化のための汎用的かつ選択的な方法を提供します.

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