N , N , N ′, N ′‐Tetrabromobenzene‐1,3‐disulfonamide and Poly( N ‐bromo‐ N ‐ethylbenzene‐1,3‐disulfonamide) as Mild and Efficient Catalysts for Solvent‐free Synthesis of N ‐Cyclohexyl‐2‐aryl(alkyl)‐imidazo[1,2‐ a ]pyridin‐3‐amine Derivatives

N ‐Cyclohexyl‐2‐aryl(alkyl)‐imidazo[1,2‐ a ]pyridin‐3‐amine derivatives have been synthesized in good to high yields from o ‐aminopyridine, aromatic and aliphatic aldehydes , and cyclohexyl isocyanide in the presence of N , N , N ′, N ′‐tetrabromobenzene‐1,3‐disulfonamide and poly( N ‐bromo‐ N ‐ethylbenzene‐1,3‐disulfonamide) as catalysts, at room temperature under solvent‐free conditions.