三次性アミドのAl(III) 触媒化されたトランスアミド化の発見とメカニズム的研究
Justin M Hoerter1, Karin M Otte, Samuel H Gellman
1Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|December 21, 2007
まとめ
Tris ((amido) aluminum ((III) 触媒は,温和な条件下で二次アミンと三次カルボキシアミドの効率的なトランスアミデーションを可能にします. この発見は,金属触媒化アミドメタテシス反応を前進させる.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- オーガニック・シンセシス オーガニック・シンセシス
背景:
- カーボキシアミドC-N結合の割れは,通常,厳しい反応条件を必要とします.
- アミド結合の機能化のためのより穏やかな方法の開発は,合成効率にとって非常に重要です.
研究 の 目的:
- 三次カルボキシアミドのトランスアミド化のためのトリソアミドアルミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノアミノア
- 実験技術と計算技術の組み合わせを用いて反応機構を明らかにする.
主な方法:
- 反応速度と速度を制限するステップを決定するための運動学的研究.
- 中間物質と触媒種を特徴付けるためのスペクトル検査方法 (例えば,NMR).
- 反応経路とエネルギー学をモデル化するための密度関数理論 (DFT) 計算.
主要な成果:
- Tris ((アミド) アルミニウム ((III)) 複合体は,Al2 ((NMe2) 6によって例示され,二次アミンと三次カルボキシアミドの容易なトランスアミド化を触媒化する.
- 触媒のサイクルには,触媒のダイマーとモノメアの添加物との均衡が伴う.
- 速度を決定するステップは,四面体中間体内の分子内核性攻撃または再配置です.
結論:
- この研究は,軽度の三次性アミドトランスミデーションのための新しい触媒システムを明らかにしています.
- 機械学的洞察は,二次アミドやプライマリアミンを含む反応との主要な違いを強調しています.
- 三次性アミド/二次性アミン系は,先進的な金属触媒化アミドメタテシスを開発する大きな可能性を示しています.
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関連する概念動画
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Aminolysis is a nucleophilic acyl substitution reaction, where ammonia or amines act as nucleophiles to give the substitution product. Acid halides react with ammonia, primary amines, and secondary amines to yield primary, secondary, and tertiary amides, respectively.
In the first step of the aminolysis mechanism, the amine attacks the carbonyl carbon of the acyl chloride to form a tetrahedral intermediate. In the second step, the carbonyl group is re-formed with the elimination of a chloride...
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01:26Preparation of 1° Amines: Hofmann and Curtius Rearrangement Mechanism
The Hofmann and Curtius rearrangement reactions can be applied to synthesize primary amines from carboxylic acid derivatives such as amides and acyl azides. In the Hofmann rearrangement, a primary amide undergoes deprotonation in the presence of a base, followed by halogenation to generate an N-haloamide. A second proton abstraction produces a stabilized anionic species, which rearranges to an isocyanate intermediate via an alkyl group migration from the carbonyl carbon to the neighboring...
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