(III) 催化 N-酸导向的 C-H 烯的化. 在温和条件下高产量,多功能合器
Baoqing Liu1, Yang Fan, Yang Gao
1Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210093, China.
Journal of the American Chemical Society
|December 13, 2012
概括
研究人员开发了一种新的Rh(III) 催化方法,用于使用N-nitroso化合物对的正极olefination. 这种多功能N-nitroso导向策略为有机合成提供了温和的条件,高产量和广泛的基质范围.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 合成方法论 合成方法论
背景情况:
- N-nitroso化合物是具有证明反应性的多功能有机结构.
- 开发高效的合成方法对于访问各种化学架构至关重要.
研究的目的:
- 开发一种由Rh (III) 催化N-nitroso导向的方法,用于的正极olefination.
- 探索这种新转型的合成效用和机械基础.
主要方法:
- 使用Rh(III) 催化剂进行N-nitroso导向的正极olefination.
- 进行了全面的机械学研究,包括交换,动态同位素效应和动态分析.
- 研究了各种Rh(III) 复合体和反应条件.
主要成果:
- 实现了温和的反应条件和高产率,用于阿伦的正极olefination.
- 证明了与具有挑战性的基质的合成兼容性,包括像1-octene.等未被激活的烯.
- 确定了催化剂静止状态为[RhCp*](2+),电友性C-H激活作为周转限制步骤,以及五个成员的rhodacycle中间体.
结论:
- 在温和的Rh(III) 催化条件下,N-nitroso组指导正极olefination.
- 这种方法提供了访问有价值的有机架构,具有广泛的基板范围.
- 该N-nitroso部分可以进一步转化为氨基功能,突出其合成多功能性.
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...
01:20Electrophilic Aromatic Substitution: Nitration of Benzene
The nitration of benzene is an example of an electrophilic aromatic substitution reaction. It involves the formation of a very powerful electrophile, the nitronium ion, which is linear in shape. The reaction occurs through the interaction of two strong acids, sulfuric and nitric acid.
01:12Preparation of Nitriles
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01:14Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
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In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...
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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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