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Updated: Jul 17, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Supramolecular structures and stereochemical versatility of azoquinoline containing novel rare earth metal complexes
A Z El-Sonbati1, R M Issa, A M Abd El-Gawad
1Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia. elsonbatisch@yahoo.com
Abstract:
Rare earth complexes of 5-(phenylazo)-8-hydroxyquinoline (HL) of composition [M(L)(2)X.H(2)O] [where M=La, Ce, Pr, Nd and X=NO(3)(-) or NCS(-)] have been prepared and characterized on the basis of their chemical analyses, (1)H NMR, magnetic measurements, conductance, and visible and IR spectral data. Composition, conductance and IR spectral data of the complexes show that the HL acts as a bidentate monobasic ligand. The visible spectra of Pr(3+) and Nd(3+) show characteristic f-f transitions, and the nephelauxetic effect (1-beta) of these transitions has been evaluated. These data indicate the weak involvement of the 4f orbitals in complex formation.
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