Samarium diiodide is an efficient catalyst for the aminolysis of either activated or non activated aziridines with aromatic amines. A variety of N-diprotected beta-diamines has been prepared including new products. The comparison of the N-protecting groups of aziridines in reactions catalyzed by samarium diiodide or by samarium iodobinaphtholate indicates that N-Boc protection leads to the best results.