在单一操作中构建4-阿扎黄核和合成欧尼
Victoria A Lehman1, Yun Ma1, Jonathan R Scheerer1
1Department of Chemistry, College of William & Mary, P.O. Box 8795, Williamsburg, Virginia 23187, United States.
The Journal of organic chemistry
|July 17, 2024
概括
研究人员在一个步骤中高效合成了4-azafluorenone核心. 这种方法为天然产品提供了一条新的途径,比如石,这是一个关键的4-azafluorenone类化合物.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 自然产品的合成自然产品的合成
背景情况:
- 4-azafluorenone类化合物家族呈现出一种独特的三环架.
- 氨酸是这个家族中已知的最简单的天然产品.
- 有效的合成路径到4-azafluorenone核心是需要进一步研究的.
研究的目的:
- 为4-azafluorenone核心开发一种新的单操作合成方法.
- 为了证明这种合成方法的实用性,通过详细阐述核心到Onychine.
- 为获得4-azafluorenone类化合物提供一个新的途径.
主要方法:
- 胺和ninhydrin之间的一步凝结反应.
- 一个1,2,4-triazine中间体的形成.
- 一个合并的 [4 + 2]/bis-retro [4 + 2] 循环加法序列,使用norbornadiene.
- 随后对合成的核心进行了进一步的阐述,使其成为石.
主要成果:
- 在单次合成操作中成功合成了4-azafluorenone核心.
- 使用了易于获得的原料.
- 中间体1,2,4-三衍生物在反应级联中起到了至关重要的作用.
- 合成的核心被有效地转化为石.
结论:
- 已经建立了一种新且高效的单步方法来构建4-azafluorenone核心.
- 这种合成策略为4-azafluorenone类化合物家族提供了一种简化方法.
- 奥尼奇因的合成证实了开发的方法的多功能性.
相关概念视频
Preparation of 1° Amines: Azide Synthesis
3.9K
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...
3.9K
Preparation of 1° Amines: Gabriel Synthesis
3.5K
Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
Strong bases like NaOH or KOH deprotonate the phthalimide to form the corresponding anion, which acts as a nucleophile. Further, the anion attacks an...
3.5K
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
3.2K
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.
3.2K
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Mechanism
3.4K
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...
3.4K
Preparation of Nitriles
2.0K
One of the common methods to prepare nitriles is the dehydration of amides. This method requires strong dehydrating agents like phosphorous pentoxide or boiling acetic anhydride for converting amides to nitriles. Another reagent namely, thionyl chloride also accomplishes the dehydration of amides, where amide acts as a nucleophile. The first step of the mechanism involves the nucleophilic attack by the amide on the thionyl chloride to form an intermediate. In the next step, the electron pairs...
2.0K
Preparation of Amides
3.0K
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...
3.0K


