アジドを水中のダイアゾ化合物に変換する
Ho-Hsuan Chou1, Ronald T Raines
1Department of Chemistry and ∥Department of Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|September 24, 2013
まとめ
私たちは,アジドを軽度な条件下でダイアゾ化合物に効率的に変換する新しいフォスフィノエステルを開発しました. この方法は,高い収穫量と幅広い機能群耐性を提供し,化学生物学におけるダイアゾ化合物の応用を拡大します.
科学分野:
- 合成有機化学 合成有機化学とは
- 化学生物学 化学生物学とは
- バイオコンジューゲーション化学
背景:
- ディアゾ化合物は,汎用性の高い合成反応剤である.
- 化学生物学におけるそれらの応用は依然として限られている.
- アジドはバイオ分子に容易に組み込まれます.
研究 の 目的:
- アジドからダイアゾ化合物を生成するための新しい方法を開発する.
- 温和で生物学的に重要な条件下で効率的なダイアゾ化合物形成を達成するために.
- 化学生物学におけるダイアゾ化学の活用のための新しい道を探求する.
主な方法:
- フォスフィノエステル反応剤の設計と合成.
- 反応条件 (pH,温度,バッファ) の最適化.
- 反応収量と機能群互換性の評価.
- 反応の進行を色測定で監視する.
主要な成果:
- フォスフィノエステルは,中性pHと室温で,リン酸バッファ内のアジドをダイアゾ化合物に効率的に変換します.
- 一般的な核愛性および電愛性機能群に対する耐性で,高収量を達成した.
- コロリメトリーを用いて反応の進行を成功裏にモニターした.
- バイオポリマー改変のための実証された可能性.
結論:
- アジドからダイアゾ化合物を生成するための新しい,効率的で穏やかな方法が確立されています.
- このフォスフィノエステル媒介反応は,化学生物学におけるアジドの有用性を拡大する.
- この方法は,バイオポリマーとリガンドの機能化に適しており,新しい研究分野を開拓しています.
関連する概念動画
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
01:371° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Mechanism
Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
01:19Diazonium Group Substitution: –OH and –H
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper...
01:22Preparation of 1° Amines: Azide Synthesis
Direct alkylation of ammonia produces polyalkylated amines, along with a quaternary ammonium salt. To exclusively prepare primary amines, the azide synthesis method can be used.
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
01:14Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
Treating arylamines with nitrous acid gives aryldiazonium salts that are effective substrates in nucleophilic aromatic substitution reactions. The diazonio group in these salts can be easily displaced by different nucleophiles, yielding a wide variety of substituted benzenes. The leaving group departs as nitrogen gas, and this easy elimination is the driving force for the substitution reaction.
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...