Sonogashira reaction on pyridinium N-heteroarylaminides

The reactivity of N-(5-iodopyridin-2-yl)aminide in a copper-free Sonogashira cross-coupling process is reported. The reaction proceeds on using PdCl2(PPh3)2 and DABCO as the base under microwave irradiation in acetonitrile or water as solvents. The process can also be carried out by traditional heating in acetonitrile on using Pd(AcO)2/DABCO with Cs2CO3.

The Sonogashira copper-free cross-coupling reaction takes place efficiently on iodoaminide 6 employing DABCO as the base and Pd(OAc)2 or PdCl2(PPh3) as palladium catalyst under microwave irradiation in acetonitrile or water as solvents yielding mono-coupled products 8.