Copper‐Catalyzed [3+2] Annulation of Pyridinium Ylides with α‐CF3 Ketones: Synthesis of Functionalized 2‐Fluoroindolizines

A copper-catalyzed [3+2] annulation of the in situ generated pyridinium ylides with α-CF₃ ketones was realized, in which α-CF₃ ketones first acted as the synthetic equivalents of unstable fluoroalkynones. With this protocol, a series of 1,3-difunctionalized 2-fluoroindolizines were afforded in moderate to good yields under ambient conditions with air as the oxidant.

Abstract

A copper-catalyzed [3+2] annulation of the in situ generated pyridinium ylides with α-CF₃ ketones was realized, in which α-CF₃ ketones first acted as the synthetic equivalents of unstable fluoroalkynones. With this protocol, a series of functionalized 2-fluoroindolizines were afforded in moderate to good yields under ambient conditions with air as the oxidant.

Zum Volltext