Angular ligand constraint yields an improved olefin aziridination catalyst

reaction: see text] The use of a pyridinophane, a macrocycle composed of three pyridines linked, via all ortho positions through CH(2) or CH(2)CH(2) groups, bound to copper, gives good performance (rate and yield) catalyzing the conversion of substituted aliphatic olefins and PhINTs to aziridines. Advantages also derive from using CH(2)Cl(2) solvent and the weakly coordinating anions BAr(4)(-) (Ar = C(6)H(5) or 3,5-C(6)H(3)(CF(3))(2)). Reactions are complete in minutes at 20 degrees C, and yields are almost quantitative for olefins not bearing secondary allylic CH bonds; however, cis-cyclooctene gives only the aziridine despite the allylic hydrogens.