グループ選択的環閉エニンメタテシス:アルキニルシリロキシ結合ダイエニンの濃度依存の選択性プロファイル

Sarah V Maifeld¹, Reagan L Miller, Daesung Lee

¹Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, USA.

Journal of the American Chemical Society

|September 30, 2004

まとめ

高度に選択的環閉メタテシスは,Grubbs触媒を用いて達成されました. より高い濃度は,急速な予備均衡を介してより小さなリングの形成を好むことにより,選択性を高めました.

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:

環閉メタテシス (RCM) は,強力な炭素-炭素結合形成反応である.
RCMにおいて,特に複雑な基板において,高い選択性を達成することは,依然として課題です.

研究の目的:

アルキニルシリロキシテザードディエニンヌの高度なグループ選択性RCMを開発する.
選択性に対する触媒生成と濃縮の影響を調査する.

主な方法:

RCM用のGrubbsの第1世代と第2世代の触媒を使用しました.
基板としてアルキニルシリロキシテザードダイニンを使用した.
選択性の効果を研究するために,反応物の濃度を変化させる.

主要な成果:

ターゲットダイエニンズの高度なグループ選択性RCMを達成しました.
より高い基板濃度で選択性の有意な増加が観察されました.
Grubbsの第1世代と第2世代の両方の触媒の有効性を実証しました.

結論:

開発されたRCM方法は,特定のアルケンの部分に対して高い選択性を提供します.
より高い濃度は,より小さなリングのより速いリング閉鎖率を好むことにより,選択性を促進します.
この研究は,複雑な分子構造のための貴重な合成ツールを提供します.

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