Zhu GD, Staeger MA, Boyd SA
Abbott Laboratories, Pharmaceutical Products Division, Metabolic Diseases Research, D4MJ, AP10, 100 Abbott Park Road, Abbott Park, Illinois 60064-6101, USA.
Org Lett. 2000 Oct 19;2(21):3345-8. doi: 10.1021/ol0064359.
An electron-donating heteroatom substituent at position-2 of a furan promotes regiospecific opening of the 7-oxa bridge of the Diels-Alder cycloadduct with hexafluoro-2-butyne, producing a 4-heterosubstituted 2,3-di(trifluoromethyl)phenol building block in a single step. The phenol and heteroatom substituent are easily transformed to the corresponding iodide or triflate that readily undergoes Heck, Suzuki, and Stille reactions to install a variety of substituents in high yields. This methodology provides a facile and general synthesis of 1,4-disubsituted 2, 3-di(trifluoromethyl)benzenes.
呋喃2位上的供电子杂原子取代基促进了与六氟-2-丁炔的狄尔斯-阿尔德环加成物的7-氧杂桥的区域特异性开环，一步生成4-杂取代的2,3-二（三氟甲基）苯酚结构单元。苯酚和杂原子取代基可轻松转化为相应的碘化物或三氟甲磺酸盐，它们能顺利进行Heck反应、Suzuki反应和Stille反应，以高收率引入各种取代基。该方法为1,4-二取代的2,3-二（三氟甲基）苯提供了一种简便通用的合成方法。
