イリジウム複合体が高度なエナンチオとダイアステロセレクティブ [2+2+2]のサイクル添加を触媒化して,軸性キラルテラリル化合物の合成を行う
Takanori Shibata1, Takayoshi Fujimoto, Kazuhisa Yokota
1Department of Chemistry, School of Science and Engineering, Waseda University, Shinjuku, Tokyo 169-8555, Japan. tshibata@waseda.jp
Journal of the American Chemical Society
|July 9, 2004
まとめ
研究者は,キラルテラリル化合物を生成するための非対称なサイクル添加を開発しました. この方法は,高純度のC2対称性ダイオール化合物の新しい源を提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- アシンメトリック・シンセシス
- カタリシス カタリシス カタリシス
背景:
- 軸性キラル化合物は,合成化学における重要な構成要素である.
- 複雑なキラル分子のエナチオセレクティブ合成のための効率的な方法の開発は,依然として重要な課題です.
研究 の 目的:
- 新しい非対称 [2+2+2]サイクル添加反応を開発する.
- 高いステレオ選択性を持つ軸性キラル型テラリル化合物を合成する.
- C2対称性ダイオール化合物の新しいキラルプールへのアクセスを提供するために.
主な方法:
- アルファ・オメガ・ダインとモノアルキン間の非対称 [2+2+2] サイクロアディション反応を用いる.
- イリジウム-キラル・フォスフィン複合体を触媒として利用する.
- 結果となるテラリル化合物の脱保護により,ダイオールが形成されます.
主要な成果:
- この反応により,様々な軸性キラル型テラリル化合物が得られました.
- 非常に高いエナチオセレクティブ性 (>99.5% ee) とダイアステレオセレクティブ性 (dl/meso = >95/5) が達成されました.
- 合成されたテラリル化合物は,ラセミゼーションなしにC2対称ダイオールに容易に変換された.
結論:
- 開発された非対称サイクロアディションは,軸性キラルテラリル化合物を合成するための効果的な方法である.
- この手順は,C2対称二醇化合物の貴重な新しいキラルプールを提供します.
- 高いステレオ選択性と容易な変換は,この合成アプローチの有用性を強調しています.
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