不对称的化反应由性双醇催化
1Department of Chemistry, Center for Chemical Methodology and Library Development, Boston University, 24 Cummington Street, Boston, Massachusetts 02215, USA.
Journal of the American Chemical Society
|May 8, 2008
概括
像 (S) - VAPOL这样的奇拉尔双,有效催化了Petasis反应,产生了有价值的奇拉尔α-氨基. 这种酶选择性合成提供了高产品产量和优秀的立体化学控制.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
背景情况:
- 酸反应是一种多组分反应,涉及酸,氨基和化物.
- 开发这种反应的酶选择性方法对于合成奇拉分子至关重要.
研究的目的:
- 为了研究使用奇拉双醇作为催化剂对enantioselective Petasis反应的使用.
- 探索反应机制并优化高产量和酶选择性条件.
主要方法:
- 使用 (S) -VAPOL (一种性双) 作为催化剂 (15mol%).
- 使用基酸盐,二次氨基和乙基酸盐作为反应剂.
- 使用3 Å分子作为添加剂.
主要成果:
- 获得了良好的至优秀的收益率 (71-92%) 的奇拉性α-氨基产品.
- 获得了高的反体比率,范围从89:11到98:2.
- 机理学研究表明,单一的配体交换和四坐标酸中间体.
结论:
- 奇拉尔双醇是选择性Petasis反应的有效催化剂.
- 开发的方法提供了一条可靠的途径来合成具有高立体化学纯度的奇拉性α-氨基.
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