基的反选择性直接催化不对称的曼尼赫式反应提供β-氨基醇
Shigeki Matsunaga1, Naoya Kumagai, Shinji Harada
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|April 17, 2003
概括
这项研究引入了一种新的催化方法,用于合成抗β-氨基醇. 该过程使用一种新型催化剂系统实现了高产量和出色的立体选择性.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 曼尼赫类反应对于合成β-氨基碳化合物至关重要.
- 开发针对反选择性曼尼赫反应的enantioselective方法仍然是一个挑战.
- 现有的方法往往缺乏补充的立体选择性或实用性.
研究的目的:
- 开发一种反选择性直接催化不对称的曼尼赫型反应.
- 为了达到高产量,在合成曼尼希 adducts. diastereoselectivity,和enantioselectivity.
- 为合成抗β-氨基醇提供一种实用且高效的方法.
主要方法:
- 使用二甲 (Et2Zn) 和 (S,S) 结合BINOL复合物作为催化剂.
- 研究了2-基-2'-甲氧基和N-二基酸胺之间的曼尼希反应.
- 使用低催化剂负载 (0.25-1mol %).
主要成果:
- 取得了优异的曼尼赫提取的收益率 (高达99%).
- 获得了高的抗选择性 (抗/syn比高达>98/2).
- 达到优异的反体过剩 (高达>99.5%).
结论:
- 与以前的方法相比,开发的催化系统提供了补充性的反选择性.
- 这提供了一条新且高效的途径,以实现对抗beta-amino酒精的对抗分子纯度.
- 易于去除保护和随时可用的起始材料和催化剂组件增强了实用性.
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