非対称なモリタ-ベイリス-ヒルマン反応は,キラルブロンステッド酸によって触媒化された
Nolan T McDougal1, Scott E Schaus
1Department of Chemistry, Metcalf Center for Science and Engineering, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, USA.
Journal of the American Chemical Society
|October 2, 2003
まとめ
チラル・ブロンステッド酸は,アルデヒドとサイクロヘクセノンの非対称なモリタ・ベイリス・ヒルマン反応を触媒化し,高収量とエナチオ選択性を達成します. この研究は,この重要な化学的変換のための最初の高度なエナンチオセレクティブ法を示しています.
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・カタリシス
背景:
- モリタ-ベイリス-ヒルマン (MBH) 反応は,貴重な炭素-炭素結合形成反応である.
- エナンチオセレクティブの変種を開発することは,キラル分子合成に不可欠です.
研究 の 目的:
- キラルブロンステッド酸を用いた新しいエナンチオセレクティブ非対称モリタ・ベイリス・ヒルマン反応を開発する.
- サイクロヘクセノンとアルデヒドのMBH反応におけるBINOL由来ブロンステッド酸の触媒活性を調べる.
主な方法:
- 触媒として,BINOL製ヒラルブレンステッド酸 (2eまたは2f) を利用した.
- 核愛性プロモーターとしてトリエチルフォスフィンを使用しています.
- サイクロヘクセノンの様々なアルデヒドとの反応を研究した.
主要な成果:
- MBH反応産物について,良好から優れた (39-88%) 収量を達成しました.
- 67%から96%のEEの範囲で,高いエナチオ選択性を得ました.
- キラルブレンステッド酸がエナチオセレクティブ性を促進する効果を示した.
結論:
- この研究では,サイクロヘクセノンの最初の高度にエナチオセレクティブな非対称MBH反応が,キラルブレンステッド酸によって触媒化されたアルデヒドと報告されています.
- 開発された方法は,価値あるキラル化合物の非対称合成のための新しい経路を提供します.
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