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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
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調節可能な封じ込めと酸性を持つイミドジフォスファート型ブロンステッド酸に対する統一アプローチ
Sebastian A Schwengers1, Chandra Kanta De1, Oleg Grossmann1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|September 3, 2021
まとめ
新しいイミドジフォスファートブロンステッド酸の 単純な合成を開発しました これらの触媒は,調節可能な酸性および限られた活性部位を提供し,高度にエナチオセレクティブな反応を可能にし,一般的な超酸性物質を上回ります.
科学分野:
- 有機合成
- カタリシス
- 酸化学
背景:
- イミドジフォスファート (IDP) ベースのブロンステッド酸は貴重な触媒です.
- 効率的な合成経路を様々なIDPのエスカファッドに開発することは依然として課題です.
- 調節可能な酸性および活性部位封じ込めは,高度な触媒アプリケーションの重要な特徴です.
研究 の 目的:
- イミドジフォスファートベースのブロンステッド酸の効率的かつ操作的に単純な合成を確立する.
- これらの新しい酸性触媒の触媒的可能性,特にエナチオ選択的変換を調査する.
- 新しい超酸性触媒のモチーフを設計し合成する.
主な方法:
- ヘキサクロビスファゾニウム塩の連続した塩化物置換による単瓶合成
- 合成されたイミドディフォスファート (IDP),イミノイミドディフォスファート (iIDP),イミドディフォスフォリミデート (IDPi) の特徴
- 硫化およびメチル化反応における触媒の酸性 (pKa) と性能の評価
主要な成果:
- 調節可能な酸度 (pKa ~11からMeCNで<2) を有するIDP,iIDP,IDPIのスキャフォールへの迅速なアクセス.
- 構造的に閉じ込められたIDP触媒を用いた高度なエナンチオセレクティブの硫化 (>95:5er) の実証.
- 新型超酸性イミドジフォスフォービス (イミノスルフォニリミノ) イミド酸 (IDPii) 触媒の開発
- シリルケテンアセタルのα-メチル化が成功し,メタノールをIDPii触媒として使用した.
結論:
- 開発された方法論は,さまざまなイミドジフォスファートベースのブロンステッド酸に簡単にアクセスできます.
- これらの触媒は調節可能な性質を持ち,挑戦的なエナチオ選択的変換を可能にします.
- 新しいIDPii超酸性物質は例外的な反応性を示し,酸性触媒の新たな道を開く.
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