A facile and efficient method for the synthesis of alkynone by carbonylative Sonogashira coupling using CHCl3 as the CO source

A facile and efficient method for the synthesis of alkynones by a Pd-catalyzed carbonylative Sonogashira coupling reaction starting from aryl iodide, terminal alkyne and chloroform (CHCl3) as the CO source is described. This procedure proves that CHCl3 is a cheap and efficient CO source in the presence of CsOH center dot H2O as the base. Furthermore, it is applied successfully for themodification of natural products, such as vindoline and tabersonin, to obtain the corresponding products in good yields.