Facile Microwave Synthesis of Pd-Catalyzed Suzuki Reaction for Bis-6-Aryl Imidazo[1,2-a]Pyridine-2-Carboxamide Derivatives with PEG3 Linker

An efficient and facile synthetic procedure has been developed for the synthesis of novel series of Bis-6-aryl-imidazo[1,2-a]pyridine-2-carboxamide containing 3,3'-((oxybis(ethane-2,1-diyl))bis(oxy))bis(propan-1-amine) derivatives (6a-6j). An application of the Palladium catalyzed Suzuki reaction on amine-(CH2)3-PEG3-(CH2)3-amine linked 6-bromo imidazo[1,2-a]pyridine-2-carboxamide was reported and their products are discussed. The reaction was optimized through numerous catalytic conditions for this strategy, and it was fixed with the best approach having advantages of less reaction time, higher degree of yield, most consumption of starting material, and selection of best catalyst for the success of the reaction. The ideal spectroscopic characterization (PMR, CMR, IR and MS) have been utilized for the finalization of the synthesized adducts.