Interaction of beta-diketones with La-III, Eu-III and Y-III complexes of the six-nitrogen-donor macrocyclic ligand C22H26N6 and crystal structure of [Eu(CH3COO){(C6H5CO)(2)CH}(C22H26N6)](CH3COO)center dot 6(H2O)

The interaction of several beta-diketones [pentane-2,4-dione, 1,3-diphenylpropane-1,3-dione, 1,1,1-trifluoro-4(2-thienyl)butane-2,4-dione] and their sodium salts with complexes of the type [ML(CH3COO)(2)]X . n(H2O), where M is La-III, Eu-III or Y-III, L is the macrocyclic ligand C22H26N6, X is Cl- or CH3COO- and n is 4-9, was investigated in solution by NMR and luminescence spectroscopy. A number of crystalline {ML}-(beta-diketonate) complexes were isolated and characterized; the structure of one member of the series, [EuL(CH3COO){(C6H5CO)(2)CH}] (CH3COO). 6(H2O), was established by X-ray crystallography. The structure is ionic; the 10-coordinate Eu-III is bonded to the six nitrogens of the macrocyclic ligand, two oxygens of a bidentate acetate and two oxygens of the chelating beta-diketonate. The coordinated acetate and the beta-diketonate are situated on opposite sides of the {EuL} macrocycle; an uncoordinated acetate provides charge neutrality. (C) 1997 Elsevier Science Ltd.