Regioselective sulfenylation of imidazoheterocycles with thiophenols at room temperature is reported. Sulfenylation is promoted by N-chlorosuccinimide under metal-free conditions with a broad range of substrate scopes.

We report herein an effective method for the halogenation of imidazo-fused heterocycles using readily available sodium salts (NaCl/NaBr/NaI) as halogen source and K 2 S 2 O 8 (or) oxone as promoter. A variety of C-3 halogenated imidazo[1,2-a]pyridines and benzo[d]imidazo[2,1-b]thiazoles were obtained in good to excellent yields. The present method of halogenation has been also extended to 2-aminopyridines, 2-aminopyrimidine, indole, and isoquinoline with moderate to excellent yields.

A one-pot three-component reaction for the regioselective synthesis of thioarylated imidazoheterocycles from aryl halides and elemental sulfur using copper(I) iodide as a catalyst has been developed. Reactions proceed with high efficiency and afford thioarylated imidazoheterocycles in good yields with broad functional group tolerance.