アルキンのアルケンとディアゼンによるTi触媒多成分酸化カルボアミネーション

Zachary W Davis-Gilbert¹, Letitia J Yao¹, Ian A Tonks¹

¹Department of Chemistry, University of Minnesota-Twin Cities , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States.

Journal of the American Chemical Society

|November 1, 2016

まとめ

この研究は,アルキンの新しいチタン触媒による酸化カルボアミネーションを導入する. この反応により,アルケン,アルキン,およびディアゼンから不飽和イミンおよびサイクロプロパンが効率的に合成される.

科学分野:

有機金属化学
キャタリシス
有機合成

背景:

酸化カルボアミネーションは有機合成における重要な変換である.
多成分反応のための効率的な触媒システムの開発は,依然として重要な課題です.

研究の目的:

アルキンの分子間または分子内酸化カルボアミン化のための新しい方法を報告する.
チタン触媒を用いてα,β-不飽和イミンとα-イミノメチル) サイクロパンの形成を調査する.

主な方法:

アルキンの機能化のために[py2TiCl2NPh]2の触媒を使用する.
アルケン,アルキン,ディアゼンを含む多成分反応を用いる.
触媒変換を駆動するTi (II) /Ti (IV) リドックスサイクルを調査する.

主要な成果:

α,β-不飽和イミンとα-イミノメチル) サイクロパネの合成に成功した.
製品の形成は,一般的なアザタナ・サイクロヘクセンの中間物質を通過する.
反応の選択性は,β-H除去またはα,γ結合を決定する基板制御によって制御される.

結論:

報告されたチタン触媒反応は,価値ある有機化合物への多用途な経路を提供します.
Ti (II) /Ti (IV) リドックスサイクルと基板制御された選択性を含むメカニズム的経路が解明されています.

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