Lithium complexation of configurational isomers of tetra-aza macrocycle containing 2,2′-bipyridine. X-Ray molecular structure of the trans-isomer of a dibutyl dicyano macrocycle

Abstract

Two configurational isomers of a dicyano dibutyl tetra-azamacrocycle containing four pyridine rings were obtained. The cis-isomer showed a higher complexing ability toward Li+ and Li+/Na+ selectivity than did the trans-isomer. The trans-isomer, the structure of which was established by X-ray analysis, displayed marked spectral changes due to significant conformational changes upon complexation.