在温和条件下对乙烯酸盐的Ni-催化基化:催化剂识别和优化
Michael Grigalunas1, Tobias Ankner2, Per-Ola Norrby1,3
1†Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States.
一个新的催化交叉合反应有效地将乙烯酸与基化物结合起来. 这种方法为合成复杂的有机分子提供了高产量.
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:
- 交叉合反应是有机合成的基础.
- 开发高效的催化系统来形成C-C键是非常重要的.
- 乙烯酸盐是多功能核友,但它们的交叉合可能具有挑战性.
研究的目的:
- 开发一种新的催化过程,用于乙烯酸和基化物交叉合.
- 为了优化反应条件,以获得高产量和广泛的基质范围.
- 为了确定活性催化物种并排除污染.
主要方法:
- 作为前催化剂,使用了 ((0) bis ((1,5-环氧八二烯) (Ni ((cod) 2).
- 采用N-异环碳 (NHC) 连接物来稳定催化剂.
- 研究了化 (LiI) 作为添加剂的作用.
- 选了各种芳香和酸酸和基化物.
- 优化反应温度和时间,以实现高效的合.
主要成果:
- 实现了芳香和酸酸和各种基化物之间的分子间合.
- 在优化条件下获得高达90%的产量.
- 确定了Ni ((cod) 2与NHC连接体和LiI相结合作为有效的催化系统.
- 证明在优化基条件下,作为催化剂是无能为力的,尽管最初的误导性结果是由于商业配体中微量污染造成的.
结论:
- 成功开发了一种强大的Ni催化基乙烯酸与基化的交叉合.
- 优化的协议为CC键形成提供了高收益率和高效的方法.
- 该研究阐明了活性催化系统,将其与潜在的催化通路区分开来.
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