Complexes of Heavy Lanthanides with o-Aminobenzoic Acid

Article abstract of DOI:10.1007/BF00809588

Anthranilates of Tb-Lu prepared in the reaction of the rare earth hydroxides with ortho-aminobenzoic acid (anthranilic acid) have the general formula Ln(C6H4NH2COO)3*2H2O where Ln=Tb, Dy, Ho, Er, Tm, Yb, Lu.The water molecules in the hydrated compounds are in the outer coordination sphere.On heating in air at 493 K dehydration occurs and the anhydrous anthranilates Ln(C6H4NH2COO)3 are formed.On the basis of the IR spectra it was found that the metal in dihydrated anthranilates was simultaneously coordinated through amino and carboxyl groups wheras in anhydrous anthranilates only through the bidentate carboxyl group.From X-ray analysis it was stated that the anthranilates Ln(C6H4NH2COO)3*2H2O are isostructural, wheras the anhydrous compounds Ln(C6H4NH2COO)3 are isostructural in the two groups Tb-Er and Tm-Lu. - Keywords: Anthranilic acid; Heavy lanthanides, complexes