基的不对称化,由奇拉二醇催化
Sha Lou1, Philip N Moquist, Scott E Schaus
1Department of Chemistry, BU Center for Chemical Methodology and Library Development, Life Science and Engineering Building, Boston University, 24 Cummington Street, Boston, MA 02215, USA.
Journal of the American Chemical Society
|September 28, 2006
概括
基拉尔BINOL衍生的二醇有效地催化了基的不对称的化. 这种方法实现了高产量和优异的酶选择性,用于合成性有机化合物.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 有机化学 有机化学
背景情况:
- 基拉尔BINOL衍生的二醇在不对称合成中是有价值的催化剂.
- 化反应对于产生碳-碳键和引入奇拉性至关重要.
- 开发高效的催化系统,以实现对酶选择性子的功能化,仍然是一个关键的挑战.
研究的目的:
- 为了研究使用奇拉BINOL衍生的二醇作为催化剂,以对子的enantioselective不对称的allylboration.
- 为了优化反应条件,包括催化剂加载和核选择.
- 为了评估发达的催化系统的产量, diastereoselectivity 和 enantioselectivity.
主要方法:
- 使用3,3'-dibromo-BINOL (3,3'-Br2-BINOL) 作为一种性催化剂.
- 采用化二氧化为化反应的核爱好者.
- 通过与酸试剂反应各种子,包括酸及其衍生物.
主要成果:
- 催化系统实现了不对称的酸盐的化. 催化系统实现了良好的至优秀的产量 (76-93%).
- 获得了高反体比率 (er = 95:5 到 99.5:0.5),证明了显著的反选择活性.
- 在涉及乙和克罗二氧酸的反应中观察到出色的二选择性 (dr >= 98:2).
结论:
- 基拉尔BINOL衍生二醇,特别是3,3'-Br2-BINOL,是子的异对称基化反应的高效催化剂.
- 开发的方法提供了一条可靠的途径,以获得具有高立体化学控制的合性合醇.
- 这种催化系统为合成复杂的性分子提供了宝贵的工具.
相关概念视频
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