An Efficient Synthetic Route to New Imidazo[1,2-a]pyridines by Cross-Coupling Reactions in Aqueous Medium

The Suzuki cross-coupling reaction of 6-bromo-3-nitro-2-phenylsulfonylmethylimidazo[1,2-a]pyridine and 6-bromo-3-nitro-2-tosylmethylimidazo[1,2-a]pyridine provided an efficient route to the corresponding 6-aryl-3-nitro-2-phenylsulfonylmethylimidazo[1,2-a]pyridines and 6-aryl-3-nitro-2-tosylmethylimidazo[l,2-a]pyridines. The reaction was catalyzed by palladium(0) in aqueous medium.