ISSN:
1573-1111
Keywords:
Tetraazacyclopentadecane
;
macrocyclic polyamine
;
anion complexation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Complexation stoichiometries and formation constants of tri- and tetra-protonated forms of 1,4,8,12-tetraazacyclopentadecane with NO 3 − , Cl−, IO 3 − and SO 4 2− ions are determined by pH potentiometric and13C NMR spectrometric measurements. Estimates of ΔH and ΔS are obtained from the values of the temperature dependent formation constants and acid dissociation constants. All four anions form only 1 : 1 complexes with the triprotonated amine species. NO 3 − and Cl− form 1 : 1 complexes only with the tetraprotonated amine, while IO 3 − and SO 4 2− form both 1 : 1 and 2 : 1 complexes. The complexation behavior is interpreted in terms of solvation and internal hydrogen bonding interactions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01041412
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