铁催化了olefins的不对称氧胺化
Kevin S Williamson1, Tehshik P Yoon
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|July 17, 2012
概括
一种新的铁催化剂使得基的区域选择性和反选择性氧胺化能够产生氨基醇. 这种方法为铜催化剂提供了补充的区域化学,使用廉价金属控制立体化学.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 基的氧胺化对于合成有价值的含化合物至关重要.
- 在有机合成中,开发高效和选择性的催化氧氨化方法仍然是一个重大挑战.
研究的目的:
- 开发一种新的铁 (II) 催化剂,用于基因的区域选择性和反选择性氧胺化.
- 与现有的铜催化方法相比,探索铁催化反应的补充区域选择性.
- 为了证明得到的oxazolidine产品在获取丰富的氨基醇方面具有实用性.
主要方法:
- 作为催化剂使用了一种新型的铁 (II) 双 (oxazoline) 复合物.
- 采用N-硫нил氧化作为氧化氨基化反应的和氧源.
- 研究了催化过程的区域选择性和反选择性.
- 操纵了oxazolidine产品以产生自由的氨基醇.
主要成果:
- 铁 (II) 催化剂成功调解了基的区域选择性和反选择性氧胺化.
- 反应产生了oxazolidine中间体,这些中间体很容易被转化为高丰富的自由氨基醇.
- 铁催化剂观察到的区域选择性与铜 ((II) 催化反应相辅相成.
- 通过在铁和铜催化剂之间进行选择,可以获得对1,2-氨基醇增强酶的两个区域异构体.
结论:
- 一种新的铁 (II) 催化剂为基的不对称氧胺化提供了一条有效的途径.
- 铁催化过程为铜催化提供了补充的区域选择性,使得各种氨基醇的区域异构体可以获得.
- 使用廉价的第一排过渡金属催化剂可以在氧齐里丁介导的氧胺反应中进行受控的区域化学.
相关概念视频
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02:04Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
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03:08Hydroboration-Oxidation of Alkenes
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02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
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Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
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