使用Et2Zn/链接-BINOL复合体的基的直接催化不对称曼尼赫式反应:合成抗或合成β-氨基醇
Shigeki Matsunaga1, Takamasa Yoshida, Hiroyuki Morimoto
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Journal of the American Chemical Society
|July 15, 2004
概括
这项研究详细介绍了一种直接的催化不对称的曼尼赫式反应,使用一种与结合的BINOL复合物. 通过调整 imine 保护组,反应有效地产生具有高立体选择性的反或 syn-beta 氨基醇.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 立体选择性合成 立体选择性合成
背景情况:
- 曼尼希反应是一种基本的碳-碳键形成反应.
- 开发催化不对称的变体对于合成性分子至关重要.
- 基基的直接催化不对称的曼尼赫式反应仍然具有挑战性.
研究的目的:
- 描述基基的直接催化不对称的曼尼赫式反应.
- 使用单一的催化系统实现高立体控制 (反或同选择性).
- 为了研究高催化剂效率和周转率数字.
主要方法:
- 作为催化剂使用了一种Et2Zn/(S,S) 结合-BINOL复合物.
- 在imine上使用不同的保护组 (N-Diphenylphosphinoyl (Dpp和Boc).
- 进行了机械学研究,以了解催化剂效率.
主要成果:
- 实现了高产量 (>99%) 和优异的反体过剩 (>99.5%) 对抗和syn-beta-amino酒精.
- 通过改变保护组,证明了可调整的立体选择性 (反/同步比>98/2或5/95).
- 观察到显著高的催化剂周转率 (TON高达4920),使催化剂负荷降低到0.02 mol %.
结论:
- Et2Zn/(S,S) 连接的BINOL复合体使得一种高效且立体选择性的直接催化不对称的曼尼赫式反应成为可能.
- 保护性小组对 imine 的操纵是控制反/syn diastereoselectivity 的关键.
- 开发的方法为不对称的曼尼赫式反应提供了先进的催化系统,具有前所未有的TON.
相关概念视频
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