Copper-Catalyzed [3 + 2] Annulation of Azides with a (Difluorovinyl)zinc Complex, Fluoroacetylene Equivalent
- Takeshi FujitaTakeshi FujitaDivision of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, JapanMore by Takeshi Fujita,
- Masafumi TakeishiMasafumi TakeishiDivision of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, JapanMore by Masafumi Takeishi, and
- Junji Ichikawa*Junji Ichikawa*Email: [email protected]Division of Chemistry, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, JapanMore by Junji Ichikawa
Abstract
The copper-catalyzed [3 + 2] annulation of organic azides with (2,2-difluorovinyl)zinc chloride–TMEDA was achieved via C–F bond cleavage. Thus, a series of 1-substituted 4-fluorotriazoles was synthesized in high yields. In this reaction, the difluorovinylzinc complex functions as an easy-to-handle equivalent of fluoroacetylene (FC≡CH) to undergo cycloaddition with azides. This work offers a facile and practical method for the use of fluoroacetylene, which has been considered to be highly reactive and difficult to handle and control for synthetic applications.