Synthesis of 4, 5-Dihydropyrrole from Γ-Nitro-nitrile

A new method for the synthesis of 4,5-dihydropyrrole derivatives from gamma-nitro-nitriles is described. In this procedure, the nitro groups of nitro-nitriles were reduced into aminoes under Fe+HCl systerm in methanol at 30 degrees Cirstly. And then the amino-groups reacted with cyano groups to form target compounds via intramolecular nucleophilic addition reaction and rearrangement reaction. Under the optimized conditions, all gamma-nitro-nitriles can be easily converted into 4,5-dihydropyrrole derivatives in satisfactory yield. It shows that the reaction has better universality. Based on the experimental results, the possible reaction mechanism was proposed.