关于使用BF3-激活型高价试剂合成3-二二的选择性
Radoslav Z Pavlović1,2, Tatjana J Kop2, Marko Nešić3
1Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States.
The Journal of organic chemistry
|July 14, 2023
概括
这项研究优化了一种制造化皮佩里丁的方法,这对于新疗法和农业化学品至关重要. 研究人员详细介绍了反应机制,改善了对选择性的控制,以便可靠地合成这些有价值的化合物.
科学领域:
- 有机化学 有机化学
- 药用化学 医学化学
- 农业化学化学 农业化学化学
背景情况:
- 化是制药和农业化学品的重要组成部分.
- 现有的合成3 - 二二烯的方法使用高价 (III) 试剂面临选择性和异位控制方面的挑战.
研究的目的:
- 为了优化反应条件,使用BF3-激活的阿里里二烯 (Aryliodine) 碳酸盐合成3-基二烯 (Fluoropiperidines) .
- 阐明控制这种转换中的立体,区域和化学选择性的机械路径.
- 提供可靠的方法,用于构建化亚热环.
主要方法:
- 对循环和非循环基质的反应参数进行系统的优化.
- 使用多核核核磁共振光谱学和标签的详细机械研究.
- 通过NMR和X射线晶体学对反应产物的结构性表征.
主要成果:
- 确定了影响选择性的关键因素,包括基质结构,BF3对的协调和电解质的作用,如四甲基四二酸 (TBABF4).
- 提出了一种反应机制,涉及BF3-协调(III) 对基的攻击,其次是确定5-exo-cyclization的 diastereodetermining.
- 通过对连接体和电解质选择的调制,对产品形成的证明控制.
结论:
- 这项研究提供了对BF3促进的N-托西胺与阿里里奥丁 (III) 碳酸盐的循环化机制的理解.
- 优化条件使得可靠和选择性合成的3 - 多二烯.
- 这些发现有助于在合成复杂的化亚热环中更广泛地应用高价值 (III) 化学.
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