イリジウム触媒によるC−C σ−結合の非対称機能化は,リング・ストレインド・ボロナート・コンプレックスによって可能
Hong-Cheng Shen1, Mihai V Popescu2, Ze-Shu Wang1
1School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K.
Journal of the American Chemical Society
|July 20, 2023
まとめ
この研究では,ビサイクロ[1.1.0]ブチル (BCB) ボロナート複合体を用いたC-C結合の非対称機能化のためのイリジウム触媒法が導入されました. この新しい反応により,独特の反添加ダイアステロ選択性を持つエンアンチオ濃縮サイクロブタンが得られます.
科学分野:
- 有機化学
- カタリシス
- 合成方法論
背景:
- オーガノボロン化合物は,有機合成と薬物の発見において重要な中間物質である.
- アルケニルボロナートのエナンチオセレクティブの1,2-メタレート再配列は,価値あるキラル反応剤への経路を提供します.
- C−C結合の非対称的な機能化は,合成化学における重要な課題である.
研究 の 目的:
- バイシクロ[1.1.0]ブチル (BCB) ボロナート複合体の,イリジウム触媒による非対称性アリレーション誘発による新しい再配置を開発する.
- C-Cシグマ結合の非対称的な機能化を達成するために,二酸化炭素化と炭化ガスを含みます.
- 合成された三次元1,1,3-三置換サイクロブタン製品.
主な方法:
- イリジウム触媒による非対称性アリレーション誘発の1,2メタラート再配置.
- ビサイクロ[1.1.0]ブチル (BCB) ボロナート複合体におけるストレイン解放を利用する.
- 実験データと密度関数理論 (DFT) の計算を用いて機械的洞察を得ている.
主要な成果:
- C-C シグマ結合の非対称機能化が成功しました
- ボロンエステルを含有する様々な1,1,3-トリスプスチートされたサイクロブタン製品へのアクセス
- 以前の *syn* 加法経路とは対照的に, *anti* 加法により生じる特異的な *trans* ダイアステレオイソーマの観察.
結論:
- 開発されたプロトコルは,複雑なキラルサイクロブタン構造を合成するための新しい効率的な方法を提供します.
- 観察された*反*加減ダイアステレオ選択性は,BCBボロナート複合体と初期の移行状態の高い核愛性によるものである.
- この研究は,非対称的な二機能化の範囲を拡大し,さらなる合成アプリケーションのための貴重な構成要素を提供します.
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