ダイアステレオ選択的に切り替え可能な,イミンによるカルバマートアンモニアムイリドのエナチオ選択的トラッピング
Jun Jiang1, Hua-Dong Xu, Jian-Bei Xi
1Department of Chemistry, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China.
Journal of the American Chemical Society
|May 11, 2011
まとめ
この研究は,キラルダイアミノ酸誘導体を合成するための新しい3つの成分反応を報告しています. この方法は,ダイアゾ化合物,カルバマート,イミンを用いて,有価な化合物への効率的かつ選択的なアクセスを提供します.
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:
- ダイアミノ酸誘導体は,医薬品化学における重要な構成要素である.
- エナチオメリックに純粋なダイアミノ酸のための効率的な合成経路の開発は,依然として課題です.
研究 の 目的:
- α,β-ダイアミノ酸誘導体を合成するためのダイアステレオ選択的に切り替えるエナチオ選択的方法を開発する.
- 迅速かつ効率的な合成のための3つの成分マニッヒ型反応を探求する.
主な方法:
- ロジウム (II) アセテートジマー (Rh) 2 (OAc) 4 (Rh) 2 (OAc) 4) とキラルブロンステッド酸コカタリストを用いた.
- ダイアゾ化合物,カルバマート,イミンを含む3つの成分反応を用いる.
主要な成果:
- 合成および抗α置換α,β-ダイアミノ酸誘導体の迅速かつ効率的な合成を達成しました.
- 化学療法,ダイアステロセレクト,およびエナチオセレクティビティの高いレベルが実証されています.
- プロティックカルバマートアンモニアムイリドのダイアステレオ選択的に切り替え可能なエナチオ選択的トラッピングが,イミンで報告されています.
結論:
- 開発された3つの構成要素のマンニッヒ型反応は,価値あるダイアミノ酸誘導体への多用途で高度に選択的な経路を提供します.
- この方法論は,ステレオ化学を正確に制御し,エナティオメリカルに純粋な化合物へのアクセスを容易にします.
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関連する概念動画
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Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
01:07Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
In the presence of an aqueous base and a halogen, primary amides can lose the carbonyl (as carbon dioxide) and undergo rearrangement to form primary amines. This reaction, called the Hofmann rearrangement, can produce primary amines (aryl and alkyl) in high yields without contamination by secondary and tertiary amines.
01:19Amines to Amides: Acylation of Amines
Various carboxylic acid derivatives (such as acid chlorides, esters, and anhydrides) can be used for the acylation of amines to yield amides. The reaction requires two equivalents of amines. The first amine molecule functions as a nucleophile and attacks the carbonyl carbon to produce a tetrahedral intermediate. This is followed by the loss of the leaving group and restoration of the C=O bond.
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
Next, the second equivalent of amine serves as a Brønsted base and deprotonates the quaternary amide...
01:29Preparation of Amides
Amides are synthesized by treating carboxylic acids with amines in the presence of dehydrating agents like dicyclohexylcarbodiimide (DCC).
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
The DCC-promoted synthesis of amides begins with the protonation of DCC by carboxylic acid. The protonation makes it a better acceptor. Next, the addition of carboxylate to the protonated carbodiimide gives a reactive acylating agent.
Subsequently, the amine acts as a nucleophile that attacks the acylating agent to form a tetrahedral intermediate. In the...
01:26Preparation of 1° Amines: Hofmann and Curtius Rearrangement Mechanism
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01:14Aldehydes and Ketones with Amines: Enamine Formation Mechanism
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