Convenient two-step one-pot synthesis of 3-substituted imidazo[1,2-a]pyridines and imidazo[1,2-b]pyridazines

A convenient and novel two-step one-pot method for the synthesis of 3-substituted imidazo[1,2-a]pyridines and 3-substituted imidazo[1,2-b]pyridazines was developed through the reaction of heterocyclic amines and N, N-dimethylformamide dimethyl acetate with active electrophiles $$\hbox {RCH}_{2}\hbox {Br}$$ ( $$\hbox {R} = \hbox {CO}_{2}\hbox {Et}$$ , CN, COPh, 4’-MeO-PhCO and 4’-F-PhCO). This protocol provides a simple and practical approach to 3-substituted fused imidazo-heterocyclic compounds in moderate to high yields. Synopsis. 3-Substituted imidazo[1,2-a]pyridines and imidazo[1,2-b]pyridazines were synthesized through a convenient, novel two-step one-pot reaction of heterocyclic amines and N,N-dimethylformamide dimethyl acetate with active electrophiles in moderate to high yields.