DMF as an amine source: iron-catalyzed cyclization of 2 H -azirines to imidazoles.

A novel method has been developed for the synthesis of 1-methyl-4,5-diaryl-1 H -imidazoles through Fe(II)-catalyzed cyclization of 2 H -azirines and N , N -dimethylformamide (DMF) as an amine source. This transformation involves the cleavage of C-N and CN double bonds and the construction of new C-N and CN double bonds. The reaction has readily available starting materials, a wide range of substrates and mild reaction conditions. In addition, the reaction also facilitated the convenient synthesis of 1-methyl-2,4,5-triaryl-1 H -imidazoles.