パラジウム触媒によるステレオ選択的O-グリコシル化で,グリカルを使用しています
Hahn Kim1, Hongbin Men, Chulbom Lee
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Journal of the American Chemical Society
|February 5, 2004
まとめ
新しいパラジウム触媒反応により,高ステレオ選択性を持つ複雑な二酸化糖類が効率的に生成されます. リガンドの選択は,アルファまたはベータグリコシドの形成を制御し,炭水化物の化学における多用途の合成経路を提供します.
科学分野:
- 炭水化物化学 炭水化物の化学
- オーガニック・シンセシス オーガニック・シンセシス
- カタリシス カタリシス カタリシス
背景:
- 伝統的なグリコシライゼーション方法は,しばしばステレオコントロールが欠けているか,または厳しい条件を必要とします.
- 複雑な炭水化物を合成するための効率的でステレオセレクティブな方法の開発は,様々な用途において極めて重要です.
研究 の 目的:
- 非常にステレオセレクティブなパラジウム触媒によるO-グリコシル化反応を開発するために.
- リガンド選択によるアノメリック立体化学の制御を実証する.
- 合成されたグリコシドの有用性を,さらなる合成変換で示します.
主な方法:
- パラジウム触媒による亜鉛 (II) アルコキシドとグリカルアセテートまたは炭酸塩の反応.
- 異なるフォスフィンリガンド (2-di-tert-butylphosphinobiphenyl vs. trimethyl phosphite) を利用して,立体化学的結果に影響を与える.
- その後,二酸化水素化,水解,水素化によるグリコシド産物の機能化.
主要な成果:
- ディサカリド形成において,良い収穫量と高いステレオ選択性を達成した.
- 2-di-tert-butylphosphinobiphenylリガンドによるベータ・グリコシドの独占的形成が実証されています.
- トリメチルフォスフィートリガンドによる好ましいアルファアノマー形成を示した.
- 不飽和グリコシドのさらなる変換を成功裏に実行しました.
結論:
- 開発されたパラジウム触媒によるO-グリコシレーションは,複雑な炭水化物を合成するための新しい,軽い,単純な方法を提供します.
- アノメリック立体化学に対するリガンド制御は,合成炭水化物化学のための強力なツールを提供します.
- この方法は,結合されたグリコシライゼーションと機能化の戦略を通じて,難しいサッカリド構造へのアクセスを可能にします.
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