由性N,N'-二氧化物- (II) 复合物催化不对称的碳烯反应:非常广泛的基质范围
Ke Zheng1, Jian Shi, Xiaohua Liu
1Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, PR China.
Journal of the American Chemical Society
|November 5, 2008
概括
一个新的 (II) -N,N'-二氧化物复合物使高度反选择性碳烯反应成为可能. 这促进了具有优异选择性和产量的有价值的α-基碳化合物的不对称合成.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 催化剂是一种催化剂.
背景情况:
- 对于生物活性分子来说,α-基碳基化合物的不对称合成至关重要.
- 开发高效的催化系统,以对酶选择性碳烯反应,仍然是一个挑战.
研究的目的:
- 开发一种新型的催化系统,用于高度反选择性碳烯反应.
- 为了合成生物相关的α-基碳烯化合物.
主要方法:
- 使用一种新的 ((II) -N,N extprime-dioxide复合物作为催化剂.
- 在温和的条件下,在糖衍生物/糖酸盐和各种基之间进行了碳烯反应.
主要成果:
- 实现了具有非常优异的enantioselectivities (97-99% ee) 的高度enantioselective碳烯反应.
- 耐受广泛的芳香性,异芳香性和异芳香性酸衍生物和酸.
- 获得高产量的产品.
- 即使降低了1mol%的催化剂负荷,也保持了高的反催化剂选择性.
结论:
- 新型的 (II) -N,N extprime-dioxide复合物是不对称的碳烯反应的有效催化剂.
- 这种方法提供了一条高效的途径,以致于以酶体丰富的α-基碳烯化合物.
- 催化系统在温和条件下和低催化剂负载下表现出强度和效率.
相关概念视频
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The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
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02:23SN2 Reaction: Stereochemistry
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