尼和阿克罗莱因的不对称1,3-双极循环添加反应与双催化剂作为奇拉的易斯酸
Taichi Kano1, Takuya Hashimoto, Keiji Maruoka
1Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|August 25, 2005
概括
一个性双- (IV) 氧化物催化剂有效地促进了不对称的1,3-双极循环添加反应. 这种方法产生具有高反选择性的异索利丁,证明其在立体选择性合成中的实用性.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 立体选择性合成 立体选择性合成
背景情况:
- 不对称的1,3-双极循环添加反应对于合成奇拉分子至关重要.
- 开发这些反应的高效和选择性催化剂仍然是有机化学的一个关键挑战.
研究的目的:
- 在不对称的1,3-双极循环添加反应中研究一个mu-oxo-类型的奇拉 bis-Titanium(IV) 氧化物催化剂 (S,S) -1 的有效性.
- 在从子和阿克罗莱因合成异索利丁的过程中实现高的异选择性.
主要方法:
- 使用了一种性 bis-Titanium(IV) 氧化物催化剂, (S,S) -1.
- 采用了不同子 (2) 和烯蛋白之间的不对称的1,3-双极循环加法反应.
- 在二甲中在-40°C进行反应.
主要成果:
- 二氧化 (S,S) -1 催化剂有效调解了循环添加反应.
- 由此产生的异佐利丁的高至优异的异选择性得到了实现.
- 一个具体的例子显示,使用二 (R = t-Bu) 和烯蛋白与10mol%的催化剂负载,对内循环载荷管道显示了97%的反体过量 (ee).
结论:
- 氧类型的奇拉 bis-Ti(IV) 氧化物 (S,S) -1 是不对称的1,3-双极循环添加的高效催化剂.
- 这种催化系统提供了一条有价值的途径,以致于以酶体丰富的异素.
- 该方法证明了复杂有机分子立体选择性合成的巨大潜力.
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