C(sp)-C(sp2) Bond Formation from Triflates via a Copper-Free Sonogashira Cross-Coupling

Abstract A rapid and copper-free Sonogashira cross-coupling enabling the direct use of aryl triflates as electrophiles is reported. The palladium-catalyzed protocol operates under simple and robust conditions, overcoming common limitations associated with triflate substrates. Broad scope is demonstrated across electron-rich, electron-neutral, moderately electron-deficient, and heteroaryl triflates, as well as diverse aromatic and aliphatic terminal alkynes. Extension to vinyl triflates further highlights the versatility of the method, offering a practical alternative to the use of corresponding aryl and vinyl halides for C(sp)-C(sp2) bond formation.