在一个enynal单位和一个enol单位之间的AuBr(3) -catalyzed [4 + 2] benzannulation中
Naoki Asao1, Haruo Aikawa, Yoshinori Yamamoto
1Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan. asao@mail.tains.tohoku.ac.jp
Journal of the American Chemical Society
|June 17, 2004
概括
埃尼纳和碳化合物的金(III) 化物催化反应有效地产生功能化芳香化合物. 这种新的化方法为合成复杂的有机分子提供了高产率的途径.
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:
- 埃尼纳和碳化合物是多功能有机构建块.
- 黄金催化已经成为有机合成中的一个强大的工具.
- 构建功能化芳香化合物的高效方法是非常受欢迎的.
研究的目的:
- 开发一种新的黄金催化反应,用于合成功能化芳香化合物.
- 探索金化物 (AuBr3) 作为化反应中的催化剂的实用性.
- 为了阐明AuBr3催化转化的反应机制.
主要方法:
- 这项研究使用了enynals,包括o-alkynylbenzaldehydes和各种碳化合物.
- 反应被一种催化剂量黄金(III) 化物 (AuBr3) 催化.
- 反应是在100°C的1,4-二氧化中进行的.
主要成果:
- 功能化芳香化合物的高产量是从埃尼纳和碳化合物的反应中获得的.
- 在AuBr3催化形式的 [4 + 2] 化过程中,通过一种涉及到pyrylium auric ate复合体形成和Diels-Alder添加的拟议机制进行.
- 与乙化合物的类似反应也提供了相应的芳香化合物,产量很好.
结论:
- 金(III) 化物是一种有效的催化剂,用于和碳化合物的化.
- 开发的方法为功能化芳香化合物提供了一个简单而高收益的途径.
- 反应机制涉及到一系列独特的黄金介导转化.
相关概念视频
Electrophilic Addition to Alkynes: Halogenation
Introduction
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
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