Diels-Alder reactions of hexafluoro-2-butyne with 2-heterosubstituted furans: A facile and general synthesis of 1,4-disubstituted 2,3-di(trifluoromethyl)benzenes

[GRAPHICS] An electron-donating heteroatom substituent at position-2 of a furan promot es regiospecific opening of the 7-oxa bridge of the Diets-Alder cycloadduct with hexafluoro-2-butyne, producing a 4-heterosubstituted 2,3-di(trifluoro methyl)phenol building block in a single step. The phenol and heteroatom su bstituent are easily transformed to the corresponding iodide or triflate th at readily undergoes Heck, Suzuki, and Stille reactions to install a variet y of substituents in high yields. This methodology provides a facile and ge neral synthesis of 1,4-disubsituted 2,3-di(trifluoromethyl)benzenes.