The collision complexes formed by caffeine and C6H6 in CCl4 were studied by NMR spectroscopy over a very wide C6H6-concn. range (£39.2 m). The ring-current shifts of the resonances can only be interpreted on the basis of a mixt. of 1:1 and 1:2 complexes. Both graphical (projection maps) and fairly sophisticated automatic minimization procedures were employed for the 1st time to ext. equil. parameters from this type of NMR data. The successful fit of the data suggests that other systems that also show unaccountable differences in formation consts. measured from different nuclei of the some acceptor mol. may contain complexes different from 1:1.
Collision complexes. 2. A proton nuclear magnetic resonance study of the complex caffeine-benzene / Andini, Salvatore; Ferrara, Luciano; Temussi, PIERO ANDREA; Lelj, F.; Tancredi, T.. - In: THE JOURNAL OF PHYSICAL CHEMISTRY. - ISSN 0022-3654. - STAMPA. - 83:13(1979), pp. 1766-1771.
Collision complexes. 2. A proton nuclear magnetic resonance study of the complex caffeine-benzene.
ANDINI, SALVATORE;FERRARA, LUCIANO;TEMUSSI, PIERO ANDREA;
1979
Abstract
The collision complexes formed by caffeine and C6H6 in CCl4 were studied by NMR spectroscopy over a very wide C6H6-concn. range (£39.2 m). The ring-current shifts of the resonances can only be interpreted on the basis of a mixt. of 1:1 and 1:2 complexes. Both graphical (projection maps) and fairly sophisticated automatic minimization procedures were employed for the 1st time to ext. equil. parameters from this type of NMR data. The successful fit of the data suggests that other systems that also show unaccountable differences in formation consts. measured from different nuclei of the some acceptor mol. may contain complexes different from 1:1.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
