ISSN:
0030-4921
Schlagwort(e):
Chemistry
;
Analytical Chemistry and Spectroscopy
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Tris(dipivaloylmethanato)europium [Eu(DPM)3]induced shifts of the proton resonances of pyridine and its 2-methyl, 3-methyl, 2,3-dimethyl and 2,5-dimethyl derivatives, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, 1,6-, 1,7- and 1,8-naphthyridine, cinnoline, phthalazine, quinazoline, quinoxaline, 1,4,5- and 1,4,6-triazanaphthalene, pteridine, acridine, phenanthridine and 1, 10-phenanthroline, have been measured for solutions containing 0·1, 0·3 and 0·5 molar equivalents of Eu(DPM)3. Differences in the behaviour of these heterocycles are discussed in terms of the steric relationship between the heterocycle and the complex. The 3 cos2 φ term, present in the expression for calculating pseudo-contact shifts, is shown to be important. The order of basicity of these heterocycles, as measured by their pKa values, cannot be used to predict the order of Eu(DPM)3 induced chemical shifts.
Zusätzliches Material:
1 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/mrc.1270030512
Permalink
