Ionic strength dependence of formation constants. Alkali metal complexes of ethylenediaminetetraacetate nitrilotriacetate, diphosphate, and tripolyphosphate in aqueous solution

1985 ◽  
Vol 57 (14) ◽  
pp. 2956-2960 ◽  
Author(s):  
Pier G. Daniele ◽  
Carmelo. Rigano ◽  
Silvio. Sammartano
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Alkali Metal ◽  
Metal Complexes ◽  
Formation Constants ◽  
Ionic Strength Dependence ◽  
Strength Dependence ◽  
Alkali Metal Complexes

Meso tetrakis ortho-, meta-, and para-N-alkylpyridiniopor-phyrins: kinetics of copper(II) and zinc(II) incorporation and zinc porphyrin demetalation

2003 ◽  
Vol 07 (03) ◽  
pp. 139-146 ◽  
Author(s):  
Peter Hambright ◽  
Ines Batinić-Haberle ◽  
Ivan Spasojević
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Effective Charge ◽  
Methyl Ethyl ◽  
Ionic Strength Dependence ◽  
Zinc Porphyrin ◽  
Cationic Porphyrin ◽  
Strength Dependence ◽  
Acid Catalyzed ◽  
Kinetics Of

The relative reactivities of the tetrakis( N -alkylpyridinium- X - yl )-porphyrins where X = 4 (alkyl = methyl, ethyl, n -propyl) , X = 3 (methyl) , and X = 2 (methyl, ethyl, n -propyl, n -butyl, n -hexyl, n -octyl) were studied in aqueous solution. From the ionic strength dependence of the metalation rate constants, the effective charge of a particular cationic porphyrin was usually larger when copper(II) rather than zinc(II) was the reactant. The kinetics of ZnOH + incorporation and the acid catalyzed removal of zinc from the porphyrins in 1.0 M HCl were also studied. In general, the more basic 4- (para-) and 3- (meta-) isomers were the most reactive, followed by the less basic 2- (ortho-) methyl to n -butyl derivatives, with the lipophilic ortho n -hexyl and n -octyl porphyrins the least reactive.

Sign in / Sign up

Export Citation Format

Share Document