催化抗马尔科夫尼科夫的维尼拉的胺化
Masaru Utsunomiya1, John F Hartwig
1Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520-8107, USA.
Journal of the American Chemical Society
|March 5, 2004
概括
催化剂使维尼拉烯与氨基的抗马尔科夫尼科夫胺化能够产生高区域选择性的β-乙胺产物. 这种新的方法有效地从 styrenes 和各种二次氨基中合成有价值的氨基衍生物.
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:
- 胺化反应对于合成氨基酸至关重要.
- 现有的方法往往缺乏区域选择性或需要恶劣的条件.
- 开发高效和选择性的胺化催化剂是一个持续的挑战.
研究的目的:
- 报道了一种新型的催化维尼拉烯的分子间胺化.
- 为了在添加二次胺到烯中实现反马尔科夫尼科夫的区域选择性.
- 探索这个新的催化系统的范围和局限性.
主要方法:
- 使用了一种含鲁催化剂系统,其中包括Ru(cod)(2-methylallyl)2,1,5-bis(diphenylphosphino) ,和三酸.
- 研究了各种二次氨基 (亚利法,基,循环) 与烯和替代烯的反应.
- 进行了对照实验,以确定连接物和酸的必要性.
主要成果:
- 从烯和各种二次氨基酸中获得β-乙烯胺产物的高产量 (64-96%) 和优异的区域选择性 (>99%).
- 证明了用乙氨基和替代氨酸的成功胺化 (51-91%的产量).
- 报道了第一个同质的过渡金属催化胺的α-甲基 styrene.
结论:
- 开发的催化剂系统提供了一个高效和高度区域选择性的路径,用于抗马尔科夫尼科夫的vinylarenes的胺化.
- 建议反应机制是直接的和不可逆转的,与催化途径不同.
- 这种方法为合成复杂的氨基结构提供了有价值的工具.
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