New Compounds of Some Trivalent Lanthanides and Actinides with Furancarboxylic Acid. Synthesis, Structure, and Absorption Spectra of the Complexes [(NH2)3C]2[M(OOCC4H3O)5] (M = La, Ce, Pr, Nd, Tb, Np, Pu, Am)

Resumo

Eight new compounds of some lanthanides and actinides with furancarboxylate anion were synthesized and studied. Their structure was determined by single crystal X-ray diffraction. All the compounds contain complex anions [M(OOCC₄H₃O)₅]^2– in which four of five furancarboxylate anions coordinate the central metal atom in the bidentate fashion via carboxy groups, whereas the fifth anion is bonded to the metal atom only via one O atom of the carboxy group. In all the complexes except the Tb compound the ether oxygen atom of the fifth furancarboxylate anion is also bonded to the metal atom; i.e., a five-membered chelate ring (МОССО) is formed. Such bond is not formed in the Tb compound. Thus, the coordination number of the central atom is 9 in the Tb compound and 10 in the other complexes.