高效的催化不对称化不受保护的β-酶胺
Guohua Hou1, Wei Li, Miaofeng Ma
1Department of Chemistry and Chemical Biology & Pharmaceutical Chemistry, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854, USA.
Journal of the American Chemical Society
|August 28, 2010
概括
一种新的催化方法使得未受保护的β-酶氨酸的高效和酶选择性化成为可能. 这提供了直接访问有价值的自由β-氨基酸,具有高产量和出色的立体控制.
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:
- β-氨基酸是药品和生物活性分子中至关重要的构建基.
- 在有机化学中,对纯β-氨基酸的高效合成仍然是一个重大挑战.
研究的目的:
- 开发一种高效且对自由β-氨基酸的合成有选择性的方法.
- 使用一种新型的催化剂,直接化不受保护的β-酶胺.
主要方法:
- 使用与 (S,S) -f-Binaphane连接体的复合物的催化系统的开发.
- 在优化的条件下,各种未受保护的β-酶胺的化.
- 使用奇拉色谱分析产品产量和反体过量 (ee).
主要成果:
- 实现了不受保护的β-酶氨酸的高效和对抗选择性化.
- 获得高产量的自由β-氨基酸 (高达97%).
- 证明了高催化活性,营业额 () 超过5000.
结论:
- 开发的Ir-(S,S) -f-Binaphane催化化是一种强大的合成纯β氨基酸的方法.
- 这种方法提供了一条简单而有效的途径,以获得有价值的性构建块.
- 催化剂的高效率和选择性为制药合成开辟了新的途径.
相关概念视频
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Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
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...
02:13Reduction 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...
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02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
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01:25Radical Anti-Markovnikov Addition to Alkenes: Overview
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02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Introduction
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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.