在催化酶选择性水合成型中应用一种性支架连接体
Amanda D Worthy1, Candice L Joe, Thomas E Lightburn
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Journal of the American Chemical Society
|October 2, 2010
概括
研究人员开发了一种新的方法来合成β-氨基化物,使用enantioselective基形成. 这种创新方法利用独特的脚手架连接物进行高效和高度选择性的化学合成.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 合成方法论 合成方法论
背景情况:
- 贝塔氨基化物是有价值的合成中间体.
- 现有的合成方法往往缺乏效率或选择性.
- 新型催化系统的开发对于推进有机合成至关重要.
研究的目的:
- 开发一种用于合成β-阿米诺-化物的enantioselective方法.
- 探索在不对称催化剂中使用新型脚手架连接体.
- 在温和的反应条件下实现高产量和酶选择性.
主要方法:
- PMP受保护的氨酸氨基的酶选择性水合成型.
- 使用一种性支架连接体,该连接体与基质结合.
- 在温和条件下进行反应 (35 °C,50 psi CO/H) (2).
主要成果:
- 成功合成β-氨基化物.
- 对于Z-olefins,获得了优异的反抗选择性 (高达93% ee).
- 证明了脚手架连接体的实用性,作为在催化量中有效的性辅助剂.
结论:
- 开发的基甲基化方法提供了一条有效的途径,以获得基丰富的β-氨基酸化物.
- 性支架配体为不对称合成提供了一种多功能策略.
- 这种方法对可扩展的性构建块的生产具有前景.
相关概念视频
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The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
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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.
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Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
Prochirality
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The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...
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Reduction of Alkenes: Catalytic Hydrogenation
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the surface of...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the surface of...


