一种催化结合策略:简单的化物催化分子间的烯氨基化
Melissa J MacDonald1, Derek J Schipper, Peter J Ng
1Center for Catalysis Research and Innovation, Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, Canada K1N 6N5.
Journal of the American Chemical Society
|November 22, 2011
概括
一种新的催化结合策略使用简单的化物前催化剂,通过分子间胺化来在室温下合成邻近的二胺. 这种方法显示了不对称催化剂的潜力,具有有前途的enantioselectivities.
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:
- 胺化反应对于合成含化合物至关重要.
- 开发高效和温和的条件,为分子间的胺化仍然是一个挑战.
- 暂时的分子内策略为控制反应性提供了新的方法.
研究的目的:
- 为室温分子间胺化引入一种催化结策略.
- 使用简单的化物预催化剂合成邻近的二胺.
- 探索这种方法在不对称催化剂中的潜力.
主要方法:
- 使用阿尔代预催化剂,从氨基胺和氧胺中形成混合氨基.
- 使用暂时的分子内分子性来促进胺化事件.
- 测试奇拉尔化物以实现对抗选择性合成.
主要成果:
- 取得了成功的室温分子间胺化.
- 维西纳胺被高效地合成.
- 使用奇拉类化物获得了有前途的enantioselectivities,证明了有效的enantioinduction.
结论:
- 催化绑定策略提供了一个温和而有效的通道到邻近的胺.
- 在催化过程中,暂时的分子内性是一种可行的策略,可以实现高的酶选择性.
- 这种方法对不对称合成应用具有重大潜力.
相关概念视频
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
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
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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.
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02:40Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
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02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
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01:21Acid-Catalyzed α-Halogenation of Aldehydes and Ketones
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