
The structures of the zinc and cadmium complexes of 4-acyl-3-methyl-1-phenyl-5-pyrazolones, [Zn(C18H23N2O2)2(H2O)] and [Cd(C28H43N2O2)2(C2H6O)2], show remarkable differences. In the case of zinc the coordination number is five and a square pyramidal structure was found, which is realised by the coordination of one molecule of water in the apical position. The coordination polyhedron is significantly distorted towards a trigonal-bipyramidal arrangement. The cadmium compound contains two coordinated ethanol molecules and is octahedral.