Equilibrium and kinetic studies of lanthanide complexes of macrocyclic polyamino carboxylates
Abstract
The stability constants (log K[sub LnL]) of lanthanide complexes of macrocyclic polyamino carboxylates, LnL (where Ln is Ce[sup 3+], Gd[sup 3+], and Lu[sup 3+] and L is DO3A = 1,4,7,10tetraazacyclododecane1,3,7triacetic acid and HPDO3A = 10(hydroxypropyl)1,4,7,10tetraazacyclododecane1,4,7triacetic acid), have been determined at 25.0 [plus minus] 0.1[degree]C and [mu] = 0.1 ((CH[sub 3])[sub 4]NCl). The stability constants of lanthanide complexes of DO3A increase with the decreasing ionic radii or increasing charge density of Ln[sup 3+]. For L = HPDO3A, the stability constant of GdL is greater than that of CeL; however the stability constants of GdL and LuL are similar. The protonation constants, K[sub H] (M[sup [minus]1]), of the LnL complexes have been determined at 25.0 [plus minus] 0.1[degree]C and [mu] = 1.0 (NaCl), and the values are 18 [plus minus] 3 for Ce(DO3A), 115 [plus minus] 8 for Gd(DO3A), 11 [plus minus] 1 for Ce(HPDO3A), and 240 [plus minus] 25 for Gd(HPDO3A). The rates of acidassisted dissociation of the protonated complexes, ML(H), have been measured at 25.0 [plus minus] 0.1[degree]C and [mu] = 1.0 (NaCl). Direct, k[sub d] (s[sup [minus]1]), and acidassisted, k[sub 1] (M[sup [minus]1] s[sup [minus]1]), dissociation rate constants are k[sub d] = (1.8 [plus minus] 0.8) [times] 10[sup [minus]3]more »
 Authors:

 BristolMyers Squibb Pharmaceutical Research Inst., New Brunswick, NJ (United States)
 Publication Date:
 OSTI Identifier:
 6708670
 Resource Type:
 Journal Article
 Journal Name:
 Inorganic Chemistry; (United States)
 Additional Journal Information:
 Journal Volume: 32:5; Journal ID: ISSN 00201669
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CERIUM COMPLEXES; DISSOCIATION; GADOLINIUM COMPLEXES; LUTETIUM COMPLEXES; CHELATES; CHEMICAL REACTION KINETICS; EQUILIBRIUM; COMPLEXES; KINETICS; RARE EARTH COMPLEXES; REACTION KINETICS; 400201*  Chemical & Physicochemical Properties
Citation Formats
Kumar, K, Chang, C A, and Tweedle, M F. Equilibrium and kinetic studies of lanthanide complexes of macrocyclic polyamino carboxylates. United States: N. p., 1993.
Web. doi:10.1021/ic00057a017.
Kumar, K, Chang, C A, & Tweedle, M F. Equilibrium and kinetic studies of lanthanide complexes of macrocyclic polyamino carboxylates. United States. doi:10.1021/ic00057a017.
Kumar, K, Chang, C A, and Tweedle, M F. Wed .
"Equilibrium and kinetic studies of lanthanide complexes of macrocyclic polyamino carboxylates". United States. doi:10.1021/ic00057a017.
@article{osti_6708670,
title = {Equilibrium and kinetic studies of lanthanide complexes of macrocyclic polyamino carboxylates},
author = {Kumar, K and Chang, C A and Tweedle, M F},
abstractNote = {The stability constants (log K[sub LnL]) of lanthanide complexes of macrocyclic polyamino carboxylates, LnL (where Ln is Ce[sup 3+], Gd[sup 3+], and Lu[sup 3+] and L is DO3A = 1,4,7,10tetraazacyclododecane1,3,7triacetic acid and HPDO3A = 10(hydroxypropyl)1,4,7,10tetraazacyclododecane1,4,7triacetic acid), have been determined at 25.0 [plus minus] 0.1[degree]C and [mu] = 0.1 ((CH[sub 3])[sub 4]NCl). The stability constants of lanthanide complexes of DO3A increase with the decreasing ionic radii or increasing charge density of Ln[sup 3+]. For L = HPDO3A, the stability constant of GdL is greater than that of CeL; however the stability constants of GdL and LuL are similar. The protonation constants, K[sub H] (M[sup [minus]1]), of the LnL complexes have been determined at 25.0 [plus minus] 0.1[degree]C and [mu] = 1.0 (NaCl), and the values are 18 [plus minus] 3 for Ce(DO3A), 115 [plus minus] 8 for Gd(DO3A), 11 [plus minus] 1 for Ce(HPDO3A), and 240 [plus minus] 25 for Gd(HPDO3A). The rates of acidassisted dissociation of the protonated complexes, ML(H), have been measured at 25.0 [plus minus] 0.1[degree]C and [mu] = 1.0 (NaCl). Direct, k[sub d] (s[sup [minus]1]), and acidassisted, k[sub 1] (M[sup [minus]1] s[sup [minus]1]), dissociation rate constants are k[sub d] = (1.8 [plus minus] 0.8) [times] 10[sup [minus]3] and k[sub 1] = (1.12 [plus minus] 0.04) [times] 10[sup [minus]1] for Ce(DO3A) and k[sub d] = (1.4 [plus minus] 0.2) [times] 10[sup [minus]4] and k[sub 1] = (2.00 [plus minus] 0.04) [times] 10[sup [minus]3] for Ce(HPDO3A). The rates of dissociation of the other complexes are first order in acid at low [H[sup +]], but the rates saturate at high [H[sup +]]. 40 refs., 5 figs., 3 tabs.},
doi = {10.1021/ic00057a017},
journal = {Inorganic Chemistry; (United States)},
issn = {00201669},
number = ,
volume = 32:5,
place = {United States},
year = {1993},
month = {3}
}