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的Pd催化氧化性正氧化C-H玻里化
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|December 14, 2011
概括
这项研究引入了一种新型的催化反应,用于对N-arylbenzamides进行C-H化. 该方法使用修改后的二乙烯 (dba) 连接体,并与各种基质取得良好的产量.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- 催化C-H功能化是有机合成中的一个强大的工具.
- 开发用于直接C-H玻利化的高效方法仍然是活跃的研究领域.
- N-基胺为开发新的合成转化提供了一个多功能平台.
研究的目的:
- 报告一种新型催化氧化性正氧化-C-H化反应的发展.
- 探索使用N-arylbenzamides的这种新型玻里化方法的范围和局限性.
- 在进一步的合成应用中证明得到的玻利酸产品的实用性.
主要方法:
- 使用了带有修改的二乙烯基 (dba) 连接体的拉催化剂.
- 采用弱基和强氧化剂来促进氧化化.
- 研究了一系列来自酸的缺电子和富电子N-arylbenzamides的反应.
主要成果:
- 实现了N-arylbenzamides的高效的催化氧化正氧化C-H玻里化.
- 确定了关键反应成分,包括改性dba联结体,弱基和强氧化剂,以获得最佳产量.
- 对胺基底的各种电子性质表现出耐受性.
- 通过随后的转化,展示了酸产品转化为各种有价值的合成.
结论:
- 成功开发了一种新的Pd催化N-arylbenzamides的ortho-C-H玻利化.
- 反应是强大的,适用于广泛的胺衍生物.
- 产生的玻利酸中间体作为进一步合成多样化的多功能构建块.
相关概念视频
02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
Diols are compounds with two hydroxyl groups. In addition to syn dihydroxylation, diols can also be synthesized through the process of anti dihydroxylation. The process involves treating an alkene with a peroxycarboxylic acid to form an epoxide. Epoxides are highly strained three-membered rings with oxygen and two carbons occupying the corners of an equilateral triangle. This step is followed by ring-opening of the epoxide in the presence of an aqueous acid to give a trans diol.
02:36Regioselectivity and Stereochemistry of Hydroboration
A significant aspect of hydroboration–oxidation is the regio- and stereochemical outcome of the reaction.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
Hydroboration proceeds in a concerted fashion with the attack of borane on the π bond, giving a cyclic four-centered transition state. The –BH2 group is bonded to the less substituted carbon and –H to the more substituted carbon. The concerted nature requires the simultaneous addition of –H and –BH2 across the same face of the alkene giving syn stereochemistry.
01:11ortho–para-Directing Activators: –CH3, –OH, –NH2, –OCH3
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03:08Hydroboration-Oxidation of Alkenes
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02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
Introduction
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02:44Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
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