Reduction and Hydrocyanation of Aziridines with C-C Bond Cleavage

The carbon-carbon bond in three-membered ring of 2,3-diaryl aziridines was reductively cleaved to give the corresponding dibenzylamine derivatives by electrocyclic ring opening of N-Li or N-Na aziridines followed by reduction of the 2-azaallyl anion formed with sodium borohydride in ethanol. Hydrocyanation of the 2-azaallyl anion with trimethylsilyl cyanide gave a secondary amine bearing a cyano group at the benzylic position. The effects of substituents on the electrocyclic ring opening of N-Li aziridines were also clarified. Unusual C-C bond cleavage of 2,3-diaryl aziridines took place to afford secondary amines by formal dihydrogenation and hydrocyanation. Formal dehydrogenation was performed by electrocyclic ring opening of N-Li or N-Na aziridines to azaallyl anions followed by reduction with NaBH4. Formal hydrocyanation was realized by treating azaallyl anions with Me3SiCN. image