Angular ligand constraint yields an improved olefin aziridination catalyst

[GRAPHICS] The use of a pyridinophane, a macrocycle composed of three pyridines linked, via all ortho positions through CH2 or CH2CH2 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 CH2Cl2 solvent and the weakly coordinating anions BAr4- (Ar = C6H5 or 3,5-C6H3(CF3)(2)). Reactions are complete in minutes at 20 degreesC, and yields are almost quantitative for olefins not bearing secondary allylic CH bonds; however, cis-cyclooctene gives only the aziridine despite the allylic hydrogens.