异酸盐的动态动力学不对称循环添加剂对维尼拉齐里丁的添加
Barry M Trost1, Daniel R Fandrick
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|September 25, 2003
概括
这项研究引入了使用维尼拉齐里丁和异酸盐的催化不对称转换,通过特定的性配体和酸性催化剂实现高反选择性 (ee),用于新型化学合成.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 有机金属化学 有机金属化学
背景情况:
- 动态运动不对称转换为奇拉分子提供了有效的路线.
- 的催化是C-N键形成的强大工具.
- 维尼拉齐里丁是多功能合成中间体.
研究的目的:
- 探索拉催化动态动态动力学非对称转换的第一个例子的raceme vinylaziridines.
- 在将维尼拉齐里丁添加到异酸盐中,以优化反应条件以获得高的异选择性.
主要方法:
- 选合性连接物,包括那些来自转-1,2-氨酸环和酸-纳酸/酸酸的衍生物.
- 对各种可催化剂的研究,重点关注pKa约为4.7.的酸.
- 对不同异酸盐电友性和N替代物对亚齐里丁的评估.
主要成果:
- 由 trans-1,2-diaminocyclohexane 和 2-diphenylphosphino-1-naphthoic 酸衍生的一种奇拉性联体表现出卓越的性能.
- 像乙酸和基二三醇这样的酸,pKa ~4.7,对于达到高反体过量 (ee) 至关重要.
- 较少的电友性异酸盐和N-基/阿里拉齐里丁产生了更好的结果,对三级C-N键形成的效果相似.
结论:
- 这项研究建立了一种有效的Pd催化方法,用于利用维尼拉齐里丁的不对称合成.
- 观察到的反应性与Curtin-Hammett场景一致,该场景涉及一个动态的pi-allyl拉中间体.
- 由此产生的产品很容易转化为有价值的伊米达佐利丁和邻近的胺.
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