ニッケル触媒化,カルボニルエネ型反応:アルファオレフィンに選択的で,電子が豊富なアルデヒドにより効率的です

Chun-Yu Ho¹, Sze-Sze Ng, Timothy F Jamison

¹Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

Journal of the American Chemical Society

|April 20, 2006

まとめ

ニッケル触媒は,アルファオレフィンとアルデヒドとの新しいカルボニルエネ反応を可能にします. この方法は,複雑な有機分子を合成するための伝統的なルイス酸触媒に多岐にわたる代替手段を提供します.

科学分野:

有機化学オーガニック・ケミストリー
カタリシスカタリシスカタリシス
合成方法論合成方法論

背景:

カーボニルエネ反応は,有機合成における炭素-炭素結合形成に不可欠である.
既存のルイス酸触媒法には,基板の範囲と反応性に関する制限があります.
新しい触媒システムの開発は,合成能力の拡大に不可欠です.

研究の目的:

新しいニッケル触媒によるカルボニルエネ型反応を記述する.
アルファオレフィンと芳香性アルデヒドまたはテルトアルキルアルデヒドを含む反応を調査する.
アリル金属反応剤の代替品として機能する触媒システムを提示する.

主な方法:

カルボニルエネ反応のニッケル・フォスフィン触媒を使用した.
アルファオレフィン,芳香アルデヒド,テルトアルキルアルデヒドを基板として使用しています.
様々な代用アルケーンとアルデヒドの反応性を研究した.

主要な成果:

単位置換アルケーンおよび芳香性/テートアルキルアルデヒドを含む有効基板が特定されました.
単位置換オレフィンの反応は,複数の置換オレフィンの反応よりも速いことが観察されました.
大量または電子が豊富なアルデヒドが,小量または電子が少ないアルデヒドよりも効果的であることが判明した.

結論:

ニッケル触媒は,カルボニルエネ型反応に強力な新しいアプローチを提供します.
記述された方法は,既存のルイス酸触媒反応を補完しています.
アルケン,シリルトリフラート,トリエチラミンとニッケル触媒の組み合わせは,アルリメタル反応剤の効果的な代替品として機能します.

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