The chiral bis(aziridines) 4, 6 and 7 have been synthesized and evaluated as chelating ligands for a variety of asymmetric transformations mediated by metals. The processes studied were the asymmetric addition of osmium tetroxide to olefins, copper-catalyzed asymmetric cyclopropanation and aziridination, palladium-catalyzed asymmetric allylic alkylation and asymmetric 1,2-addition of organolithium reagents to imines. In the best cases an enantiomeric excess > 95% was obtained.
The chiral bis(aziridines) 4, 6 and 7 have been synthesized and evaluated as chelating ligands for a variety of asymmetric transformations mediated by metals. The processes studied were the asymmetric addition of osmium tetroxide to olefins, copper-catalyzed asymmetric cyclopropanation and aziridination, palladium-catalyzed asymmetric allylic alkylation and asymmetric 1,2-addition of organolithium reagents to imines. In the best cases an enantiomeric excess > 95% was obtained.