Comparative stability constants for metal ions with tetraazamacrocycles of various ring sizes carrying a single amine or carboxylate pendant group
GA Lawrance, Y Baran, A Bayada, PG Lye, M Maeder, EN Wilkes
article (Uluslararası, Hakemli) | Yazar(lar): GA Lawrance, Y Baran, A Bayada, PG Lye, M Maeder, EN Wilkes | Yıl: 2003 | Dergi/Kurum: TRANSITION METAL CHEMISTRY | İndeks: WOS.SCI — Özet: Acid dissociation constants for a series of tetraazamonocycloalkanes of {13}-{15} membered ring sizes, as well as for a related 'reinf
Acid dissociation constants for a series of tetraazamonocycloalkanes of {13}-{15} membered ring sizes, as well as for a related 'reinforced' {15R} tetraazabicycloalkane, each with one primary amine or carboxylate C-pendant, are reported. Further, formation constants with the metal ions Zn-II, Cd-II, Pb-II, Hg-II, Mn-II and Co-II have been determined. The ligands differ in their selection of metal ions, reflected in the formation constants for 1:1 complexation (K-ML). Differences arise in part from the increasing ring size or rigidity and also from the availability of potential pendant O-donors versus N-donors in stepping from amine to carboxylate pendant ligands, implying a role for the pendants in binding the metal ions.