通过Horner-Wadsworth-Emmons反应在深层欧性溶剂中的α,β-不和的增强型立体选择合成
Andrea Nicola Paparella1, Margherita Stallone1, Mara Pulpito1
1Dipartimento di Farmacia-Scienze del Farmaco, Università di Bari "Aldo Moro", Consorzio C.I.N.M.P.I.S., Via E. Orabona, 4, 70125 Bari, Italy. filippo.perna@uniba.it.
Organic & biomolecular chemistry
|February 13, 2024
概括
通过使用深层环氧溶剂,实现了乙烯胺衍生物的绿色合成. 这种可扩展的Horner-Wadsworth-Emmons反应为有价值的不和 Ester提供了一条可持续的途径.
科学领域:
- 有机化学 有机化学
- 绿色化学 绿色化学
背景情况:
- 霍纳-瓦兹沃斯-埃蒙斯反应是合成α,β-不和的关键方法.
- 传统方法通常涉及恶劣的条件或有毒的溶剂,造成环境问题.
研究的目的:
- 开发一种可扩展的,环保的 (E) -α,β-不和的合成方法.
- 为了利用可生物降解的深度环氧溶剂 (DES) 进行霍纳-瓦兹沃思-埃蒙斯反应.
主要方法:
- 霍纳 - 沃兹沃斯 - 艾蒙斯反应是在三乙酸和 (异质) 芳香碳化合物之间进行的.
- 作为反应介质,使用了有毒,无毒和生物降解的DES,特别是胆化物/尿素.
- 在室温和空气下进行反应,使用LiOH,K2CO3或DBU等基.
主要成果:
- 成功开发了 (E) -α,β-不和的可扩展合成,包括乙基酸盐衍生物.
- 这种反应表明对非替代或三替代产品具有很高的立体选择性.
- 胆化物/尿素DES可以在三个周期内重复使用,而不会显著地降低效率.
- 格拉姆尺度 (10毫摩尔) 的反应没有副作用,产生了71.1的生态尺度得分.
结论:
- 深度环氧溶剂为霍纳-瓦兹沃思-埃蒙斯反应提供了可持续和高效的介质.
- 这种方法提供了一种绿色和可扩展的方法来合成有价值的不和 Ester.
- DES的可重复使用性突出了其在经济高效和环保的化学合成方面的潜力.
相关概念视频
01:14Alkylation of β-Diester Enolates: Malonic Ester Synthesis
3.4K
Malonic ester synthesis is a method to obtain α substituted carboxylic acids from ꞵ-diesters such as diethyl malonate and alkyl halides.
3.4K
01:26Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction
3.4K
α-Substituted ketones or aldehydes can be synthesized from enamines by the Stork enamine reaction, named after its pioneer Gilbert Stork. Enamines are useful synthetic intermediates where the lone pair on nitrogen is in conjugation with the C=C bond. They resemble enolate ions, as the resonance forms of both species have a nucleophilic α carbon.
3.4K
01:07Alkylation of β-Ketoester Enolates: Acetoacetic Ester Synthesis
3.3K
Acetoacetic ester synthesis is a method to obtain ketones from alkyl halides and β-keto esters. The reaction occurs in the presence of an alkoxide base that abstracts the acidic proton of the β-keto esters. The step results in an enolate ion which is doubly stabilized. The enolate then reacts with an alkyl halide via the SN2 process to produce an alkylated ester intermediate with a new C–C bond. The hydrolysis of the intermediate, followed by acidification, results in an...
3.3K
01:18β-Dicarbonyl Compounds via Crossed Claisen Condensations
3.1K
Crossed Claisen condensations are base-promoted reactions between two different ester molecules producing β-dicarbonyl compounds. The reaction involving esters, with both containing α hydrogen, results in a mixture of four different products that are difficult to isolate. This reduces the synthetic utility of the reaction.
3.1K
02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
10.2K
Alkenes are converted to 1,2-diols or glycols through a process called dihydroxylation. It involves the addition of two hydroxyl groups across the double bond with two different stereochemical approaches, namely anti and syn. Dihydroxylation using osmium tetroxide progresses with syn stereochemistry.
10.2K
01:19α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
2.9K
The pinacol and McMurry reactions involve the reductive coupling of ketones or aldehydes. Similarly, the bimolecular reductive coupling of two ester molecules in the presence of sodium metal in an aprotic solvent yields an α-hydroxy ketone product. The α-hydroxy ketone is also called acyloin, so the reaction is referred to as ‘acyloin condensation.’
2.9K