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多様なオーソ-C ((sp²) -H トランジエント・ディレクティング・グループを用いたベンザルデヒドの機能化

Xi-Hai Liu¹, Hojoon Park², Jun-Hao Hu¹

¹School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology , Wuhan 430070, People's Republic of China.

Journal of the American Chemical Society

|December 23, 2016

まとめ

この研究は,ベンザルデヒドの多用途のオーソ-C ((sp2) -H機能化のための新しい一時的な指向グループ戦略を導入する. この方法は,補助基なしでパラジウム触媒によるアリレーション,塩素化,ブロミネーション,およびイリジウム触媒によるアミデーションを可能にします.

科学分野:

有機化学
カタリシス
合成方法論

背景:

暫定的な誘導群を用いたパラジウム触媒によるC-H機能化は,主にC-Hアリレーションに限定される.
ベンザルデヒド基板は,潜在的触媒中毒および競合する誘導群により,C-H活性化に特異的な反応性課題を有する.

研究の目的:

ベンザルデヒドの多用途のオルトC ((sp2) -H機能化戦略を開発する.
トランジエント・ディレクティング・グループを用いたアリレーションを超えて,金属触媒によるC-H機能化の範囲を拡大する.
複雑な分子合成における開発方法の適用性を実証する.

主な方法:

ベンザルデヒド基板のイミン結合による一時的な誘導群の局所形成.
パラジアム (II) 触媒によるC-Hアリレーション,塩素化,およびブロミン化.
イリジウム (III) 触媒化C-Hアミデーション

主要な成果:

ベンザルデヒドの多種多様なオーソ-C ((sp2) -H機能化,アリレーション,塩素化,ブロミン化,およびアミデーションを達成した.
暫定的な指揮グループが他の調整機能グループを有効に覆すことが示された.
薬剤同類体の後期多様化のための方法論を成功裏に適用した.

結論:

暫定的な指向グループ戦略は,ベンザルデヒドの金属触媒化C-H機能化の範囲を大幅に拡大します.
このアプローチは複雑な有機分子を合成し,薬の類似性を機能化するための強力なツールを提供します.
開発された方法は,以前の戦略の限界を克服し,高効率で複数の反応タイプを可能にします.

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