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
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.
Zhu
GD
Abbott Laboratories, Pharmaceutical Products Division, Metabolic Diseases Research, D4MJ, AP10, 100 Abbott Park Road, Abbott Park, Illinois 60064-6101, USA.
Staeger
MA
Boyd
SA