通过C-H键激活对异环的Rh (I) 催化结合:通过机械洞察扩大了范围
Jared C Lewis1, Ashley M Berman, Robert G Bergman
1Department of Chemistry, University of California and Division of Chemical Sciences, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|February 7, 2008
概括
一种新的Rh催化直接化方法可以有效地合亚醇和亚醇化物. 这种功能组耐受性过程使用了一种新联体,简化了反应和产品分离.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 药用化学 医学化学
背景情况:
- 异环环的直接结合对于合成药物相关化合物至关重要.
- 使用 (Pd) 或铜 (Cu) 催化剂的现有方法往往缺乏功能组耐受性,并且需要严苛的条件.
- 亚醇是重要的药解体,由于其电子性质,它们对直接结具有独特的挑战.
研究的目的:
- 开发一种新,实用和功能群耐受的方法,用于直接与化的化和化.
- 为了确定一个高度活跃和热稳定的催化剂系统进行这种转换.
- 建立反应条件,简化处理,净化,并与微波合成兼容.
主要方法:
- 使用 (Rh) 催化直接化,使用化.
- 使用一种易于制备的,低分子量联体,Z-1-tert-butyl-2,3,6,7-tetrahydrophosphepine,它以双重的P-olefin方式与Rh协调.
- 使用相应的的四甲盐进行空气稳定的组装,并在THF或二氧化中进行反应.
主要成果:
- 成功地用化对各种药用重要醇进行直接化.
- 已证明功能组耐受性,适应与Pd或Cu催化剂不兼容的合伙伴.
- 使用微波加热,在2小时内获得了优异的产品产量.
- 与传统的高沸胺溶剂相比,简化了反应设置和产品分离.
结论:
- 开发的Rh催化方法提供了一种实用和高效的途径,用于直接化醇.
- 新型的氨酸连接体和反应条件提供了一个强大而多功能的催化系统.
- 这种方法促进了复杂的醇衍生物的合成,在药物化学中具有广泛的应用.
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