In situで組み立てられたボロナートエステルは,キラルカルボキシル酸を助成し,非対称なトランス-アジリジナーションを触媒化した
Takuya Hashimoto1, Alberto Osuna Gálvez, Keiji Maruoka
1Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|November 9, 2013
まとめ
キラルダイオールと2-ボロノベンゾ酸を用いた新しいキラルブロンステッド酸触媒が開発されました. この新しい触媒は,特にN-ベンジルイミンのトランスアジリディネーション反応において,高いエナンチオセレクティブ性を達成します.
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
- アシンメトリック・シンセシス
背景:
- チラル・ブロンステッド酸触媒は,非対称合成に不可欠です.
- N-ベンジルイミンなどの難題のある基板のための効率的な触媒の開発は,依然として活発な研究分野です.
研究 の 目的:
- 非対称的なトランス-アジリディネーションのための新しいキラルブレンステッド酸触媒を開発する.
- 独立した有機分子から活性触媒の in situ 形成を調査する.
- N-BocとN-ベンジルイミンのトランスアジリディネーションにおいて,高いエナンチオ選択性を達成する.
主な方法:
- キラルダイオールと2-ボロノベンゾ酸から新しいキラルブロンステッド酸触媒の合成.
- 活性触媒種を生成するボロナートエステルの局所形成.
- N-フェニルジアゾアセタミドを用いたN-BocおよびN-ベンジルイミンのトランスアジリディネーションに触媒を適用する.
主要な成果:
- 新型キラルブロンステッド酸触媒の開発に成功.
- ボロナートエステルの in situ 形成を重要な触媒プロセスとして実証.
- N-BocとN-ベンジルイミンのトランスアジリディネーションで得られた高いエナンチオ選択性.
- N-ベンジルイミンで高いエナンチオ選択性を達成する最初の報告された触媒.
結論:
- 新しく効果的なキラルブレンステッド酸触媒が成功裏に開発されました.
- 局所生成のボロナートエステル触媒は,効率的な非対称なトランス-アジリディネーションを可能にします.
- この研究は,挑戦的なN-ベンジルイミンを用いた触媒的非対称合成の重要な進歩を提供します.
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