Premium
Metal Complexes with Macrocyclic Ligands. X . On the metal complexation kinetics of two N 4 ‐macrocycles containing a pyridine ring
Author(s) -
SchultzGrunow Philipp,
Kaden Thomas A.
Publication year - 1978
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19780610702
Subject(s) - chemistry , pyridine , protonation , metal , kinetics , ring (chemistry) , metal ions in aqueous solution , ligand (biochemistry) , ring size , reaction rate constant , polymer chemistry , crystallography , inorganic chemistry , ion , stereochemistry , medicinal chemistry , organic chemistry , receptor , biochemistry , physics , quantum mechanics
The complexation kinetics of the two macrocycles 1 and 2 with Co 2+ , Ni 2+ , Cu 2+ and Zn 2+ have been measured by pH‐stat techniques. The rates are first order in metal and ligand concentration and depend upon the pH. This results from the different reactivities of the various protonated species of the macrocyclic tetraamines. The resolved rate constants are given in Table 2 . In comparison with other 14‐membered cyclic aliphatic tetraazasystems 1 and 2 react more slowly with metal ions. This might be a consequence of the more rigid structure induced by the pyridine ring.