ISSN:
0009-2940
Keywords:
Amides
;
Barbiturates
;
Hydrogen bonds
;
Linear free-energy relations
;
Solvent effects
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
NMR Shift titrations with 2,6-diacyldiaminopyridines as well as with the parent benzene derivative and barbiturates indicate strong hydrogen bond attenuation by steric hindrance, by flexible side chains, and by chloroform as solvent. Analysis of unhindered associations and of corresponding host-guest complexes reported in the literature shows a linear correlation of complexation free energy ΔG° with the number n of hydrogen bonds for n 〉 1, which amounts to ΔG° = (5 ± 1) kJ/(mol · n) in CDCl3; this value is expected to increase in carbon tetrachloride to ΔG° ≈ 10 kJ/(mol · n) as judged by extrapolation from 2 measurements.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19891220631
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