Bis[(R)-2-methyl-1,4,7-triazacyclononane] cobalt(III), nickel(II), and copper(II) complexes

Abstract

Abstract Bis[(R)-2-methyl-1,4,7-triazacyclononane]cobalt(III), nickel(II), and copper(II) complexes have been prepared and characterized. The cobalt complex is separated into five components although there are nine possible isomers. The nickel and copper complexes were not separated into isomers. Since these optical active complexes contain, to a first approximation, no chiral chelate ring configuration, the optical activity results only from λ conformations of the six chelate rings. It is noteworthy that all the complexes show very strong positive CD extremes in the region of the first spin allowed d-d transitions in O h symmetry.