离子液促进的,高度区域选择性的,由烯化物对电子丰富的烯酸进行赫克化
Jun Mo1, Lijin Xu, Jianliang Xiao
1Department of Chemistry, Liverpool Centre for Materials and Catalysis, University of Liverpool, Liverpool L69 7ZD, UK.
Journal of the American Chemical Society
|January 13, 2005
概括
使用离子液体进行催化赫克化,可有效合成分支,化烯. 这种方法提供了高的区域选择性与多样化的烯化物,优于传统的分子溶剂.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 绿色化学 绿色化学
背景情况:
- 赫克反应是一个重要的碳-碳键形成反应.
- 传统的赫克反应通常依赖于昂贵且无法获得的酸.
- 在与电子丰富的烯酸反应的Heck反应中实现高区域选择性可能是具有挑战性的.
研究的目的:
- 开发一种区域选择性催化赫克化方法,使用易于获得的化和化.
- 为了研究使用伊米达离子液体作为Heck arylation的反应介质.
- 探索以多种替代剂合成有分支的,合的烯酸.
主要方法:
- 帕拉催化了乙烯基乙烯,化物和化三甲基的赫克化.
- 使用伊米达离子液体作为反应介质.
- 采用一系列的化和化作为合伙伴.
主要成果:
- 在imidazolium离子液体中实现了高效率和显著的区域选择性.
- 反应只产生了分支的,合的烯酸,用烯酸替换alpha到 heteroatom (对于乙烯基乙和胺) 或β到 heteroatom (对于allyltrimethylsilane).
- 相比之下,分子溶剂中的反应产生了区域异构体的混合物.
结论:
- 伊米达离子液体在催化赫克结合中促进了独特的区域控制.
- 这种方法提供了一种简单,有效和更绿色的替代方法,用于合成分支,联烯酸.
- 开发的化学扩大了赫克反应的范围,包括了更广泛的基质和化剂.
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