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A highly efficient protocol for the copper and phosphine free Sonogashira cross-coupling reactions of aryl iodides with terminal alkynes under aerobic conditions has been developed. Using 1 mol % of the palladium-bis(oxazoline) complex, Pd-BOX A, in the presence of KOH, and a CH 3 CN–H 2 O solvent system allowed for the cross-coupling reactions to proceed at room temperature or 60 °C. This new catalytic system was found to be highly active for the cross-coupling reaction of aryl diiodo substrates with unactivated alkyl alkynes to produce various symmetrical dialkynes, as well as for the cross-coupling of terminal dialkynes with aryl iodides to generate symmetrical disubstituted internal alkynes.

An efficient catalytic system for the title cross coupling reactions based on a novel palladium-bis(oxazoline) complex is developed which exhibits exceptional air and moisture stability.