ロジウム (III) 含有サイクロヘキサディエノンの非対称ボリレーティブサイクリング:実験的およびDFT研究
Yun-Xuan Tan1, Fang Zhang2, Pei-Pei Xie3
1CAS Key Laboratory of Synthetic Chemistry of Natural Substances, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.
Journal of the American Chemical Society
|July 27, 2019
まとめ
この研究は,最初のロジウム (III) 触媒による1,6-ダイエンの非対称なボリラティブサイクリングを導入する. この方法は,複数のステレオセンターを持つ光学的に純粋なシス・バイサイクル化合物を効率的に生成します.
科学分野:
- 有機化学
- カタリシス
- ステレオ選択合成
背景:
- 1,6-ダイエンの金属触媒による非対称サイクリングでオレフィンを区別することは本質的に困難である.
- 複数のステレオセンターを持つ複雑なバイサイクル構造を合成するための効率的な方法の開発は,有機化学における課題です.
研究 の 目的:
- サイクロヘキサディエノン系1,6ダイエンの最初のロジウム ((III) 触媒による非対称なボリラティブサイクライゼーションの開発.
- 光学的に純粋なシス・バイサイクルの骨格の合成で高い収量とステレオ選択性を達成する.
主な方法:
- ロジウム (III) 触媒による非対称なボリラティブサイクル反応.
- サイクロヘクサディエノン系モノ-1,1-ディ-,および (E) -1,2-非置換アルケーン (1,6-ディエネ) を利用した.
- SAESI-MS (スキャニング・エレクトロスプレー・イオニゼーション・マス・スペクトロメトリー) と,触媒サイクルを明らかにするための計算研究を用いた.
主要な成果:
- 3つまたは4つの隣接するステレオセンターを持つ光学的に純粋なシス・バイサイクルの骨格を成功裏に合成しました.
- 高い収量 (25~93%) と優れたダイアステレオ選択性 (> 20:1 dr) とエナチオ選択性 (90~99% ee) を達成した.
- 幅広い機能群との互換性が実証され,製品変換が容易である.
結論:
- 1,6-ダイエンの新しいロジウム ((III) 触媒による非対称なボリラティブサイクリングを確立した.
- 酸化添加,オレフィン挿入,結合添加,還元性除去などの主要なステップを含むRh (I) / (III) 触媒サイクルを提案した.
- リングストレスの役割は,地域選択性を制御し,5,6回転構造の形成を促進し,将来の反応設計の基礎を提供することを強調した.
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