Probing the capabilities of copper complexes with nitrogen and sulfur containing macrocyclic ligands as aziridination catalysts

Aziridines are three:membered rings containing one nitrogen atom. They are useful as synthetic intermediates in many organic reactions. Much work has been devoted to synthesizing their analogs, cyclopropanes and epoxides, but little work has been done on the aziridination reaction. This study endeavored to probe the efficiencies of novel copper aziridination catalysts with N3 and 53 macrocyclic ligands compared to an N5 2 analog for the reaction with the nitrene precursor (N-(para­ tosylsulfonyl)imino)phenyliodinane, PhINTs, and the olefin styrene. The nitrogen containing catalyst complex: gave higher yields than the sulfur containing catalyst complex. Both ligands were found to decrease the yield of the aziridination reaction relative to the catalyst complex Cu(acach, However, for the N3 ligand system, only a slight decrease occurred and the possibility remains that the system could be adjusted to obtain higher yields. Preliminary studies using an N5 2 macrocyclic ligand in the copper catalyst complex showed it to have slightly higher yields than the N] and 53 systems.