Synthesis and crystal structure of two praseodymium 2-iodobenzoic acid complexes

Two new complexes, {[Pr(2-IBA)3 · 2,2′-bipy]2·[Pr(2-IBA)3 · 2,2′-bipy]2 · 0.5C2H5OH · H2O} (1) and [Pr(2-IBA)3 · phen]2 (2) (2-IBA = 2-iodobenzoate; 2,2′-bipy = 2,2′-bipyridine; phen = 1,10-phenanthroline) were synthesized, and their crystal structures were determined by X-ray diffraction. Complex 1 consists of two binuclear molecules [Pr(2-IBA)3 · 2,2′-bipy]2 (a) and [Pr(2-IBA)3 · 2,2′-bipy]2 (b), half uncoordinated ethanol and one uncoordinated water. In the two molecules (a) and (b), the coordination environment of central ions is similar. The Pr13+ ion in molecule (a) and Pr23+ ion in molecule (b) are nine-coordinate with seven oxygen atoms from five 2-IBA ligands and two nitrogen atoms from one 2,2′-bipy molecule. The crystal structure of complex 2 is similar to that of binuclear [Pr(2-IBA)3 · 2,2′-bipy]2 in complex 1.