由利性易斯酸催化的2-二烯-4-酸的高度反选择性1,3-双极循环添加反应
Hiroyuki Suga1, Kei Inoue, Shuichi Inoue
1Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, Wakasato, Nagano 380-8553, Japan. sugahio@gipwc.shinshu-u.ac.jp
Journal of the American Chemical Society
|December 12, 2002
概括
奇拉尔易斯酸催化剂,特别是稀土金属三酸复合物与2,6-bis(oxazolinyl) 化 (Pybox),使2-二-4-酸盐的高度反选择性1,3-双极循环添加成为可能.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
背景情况:
- 1,3-双极循环添加反应对于合成异环化合物至关重要.
- 在这些反应中达到高的酶选择性对于产生性分子至关重要.
研究的目的:
- 为了研究使用合的2,6-bis(oxazolinyl) pyridine (Pybox) -稀土金属三酸复合物作为易斯酸催化剂.
- 为了在2-二-4-酸盐的1,3-双极循环添加剂中实现显著的反反选择性.
主要方法:
- 作为易斯酸催化剂,利用了奇拉Pybox-稀土金属三复合物.
- 与各种基质进行了1,3-双极循环添加反应,包括氧甲基衍生物,酸和3-烯-2-氧利丁.
- 使用不同Pybox配体 (i-Pr和Ph) 的基于 (Sc(III)) 和 (Yb(III)) 的催化剂.
主要成果:
- 在Sc(III) -Pybox-i-Pr催化反应中,产生的内附产物具有高达93%的反体过量 (ee).
- 与基酸盐的反应产生了具有87% ee 的外附产物.
- Yb(III) -Pybox-Ph有效地催化了与3-烯基-2-oxazolidinone的反应,产生了具有98% ee.e的外附加物.
结论:
- 奇拉尔Pybox-稀土金属三酸复合物是对对抗选择性1,3-双极循环添加物的有效催化剂.
- 金属和Pybox配体的选择会影响反应的立体化学结果 (内/外) 和酶选择性.
相关概念视频
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