Coordination of lanthanides by two polyamino polycarboxylic macrocycles: formation of highly stable lanthanide complexes

Journal Article · Wed Jul 16 00:00:00 EDT 1986 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic00235a031· OSTI ID:5459525

Loncin, M F; Desreux, J F; Merciny, E

The formation constants of a few lanthanide complexes with DOTA (1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) and TETA (1,4,8,11-tetraazacyclotetradecane-N,N',N'',N'''-tetraacetic acid) have been measured by potentiometric and competition methods. The ligand DOTA forms the most stable lanthanide chelates known so far (log K/sub ML/ = 28.2-29.2) while the stability of the TETA compounds at 80 /sup 0/C (log K/sub ML/ = 14.5-16.5) is comparable to the stability of the EDTA complexes. A competition method with the oxalate anion as a probe had to be used for determining the formation constants of the DOTA lanthanide chelates because of the high stability of these compounds. The relative stability of the DOTA and TETA complexes in accounted for by steric factors with reference to known solution- and solid-state structures. 20 references, 2 tables.

• Research Organization: Univ. of Liege, Belgium
• OSTI ID: 5459525
• Journal Information: Inorg. Chem.; (United States), Vol. 25:15
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBOXYLIC ACIDS
STABILITY
SYNTHESIS
ORGANIC NITROGEN COMPOUNDS
RARE EARTH COMPLEXES
EXPERIMENTAL DATA
COMPLEXES
DATA
INFORMATION
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
400201* - Chemical & Physicochemical Properties
400301 - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)