催化不对称的未被激活的基因的硫功能化
Scott E Denmark1, David J P Kornfilt, Thomas Vogler
1Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, Illinois 61801, United States. sdenmark@illinois.edu
Journal of the American Chemical Society
|August 24, 2011
概括
这项研究引入了一种新型的双键的催化不对称硫化,使用基于BINAM的色胺催化剂. 这种方法有效地从和烯中产生硫化循环化合物,具有悬挂函数组.
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:
- 双键的硫化是有机合成中的一个关键转化.
- 开发高效和立体选择性的硫化方法仍然是一个挑战.
研究的目的:
- 开发和烯的催化不对称硫化.
- 为了利用基于BINAM的光胺催化剂进行这种转化.
主要方法:
- 使用基于BINAM的酸胺催化剂.
- 使用电友硫源进行反应.
- 研究与悬挂氧基或氧基组的循环化.
主要成果:
- 实现了简单和烯的催化不对称硫化.
- 通过分子内循环化合成硫化四基和四基.
- 证明了与酒精和碳素酸的分子间二元功能化.
结论:
- 开发的方法提供了一个有效的途径,以立体定义的硫化循环化合物.
- 催化剂系统是多功能性的,可以实现分子内循环和分子间的硫功能化.
相关概念视频
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...
02:24Reduction 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.
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02:47Alkynes to Aldehydes and Ketones: Hydroboration-Oxidation
Introduction
One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
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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.
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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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