Efficient synthesis of ynones from carboxylic acids and terminal alkynes via Pd/Cu catalysis using 2-chloroimidazolium chloride as the activation reagent

Abstract

In this work, we have developed a successful Sonogashira coupling reaction utilizing IPrCl-Cl as the activation reagent to couple carboxylic acids with terminal alkynes. The reaction employs CuI/Pd(PPh₃)₂Cl₂ as the co-catalyst and Et₃N as the solvent, resulting in excellent yields (up to 88%) of ynones. The use of carboxylic acids as a starting material makes this method a valuable contribution to organic synthesis.