An Na-8 cluster in the structure of a novel oxamato-bridged (NaCuII)-Cu-I three-dimensional coordination polymer

The new heterometallic sodium(I)-copper(II) compound Na4Cu2 (2) . 10.5 H2O (3), where H-8[2] stands for N,N',N ",N'''-methanetetrayltetrakismethylenet etrakis (oxamic acid), has been synthesized and its crystal structure deter mined by single-crystal X-ray diffraction. The structure of 3 consists of c ationic [Cu-2(eta(4):eta(4)-2](4-) dinuclear units, coordinated sodium cati ons, and water molecules. In the crystal, the dinuclear copper entities are joined through discrete aggregates of eight sodium atoms linked by oxamato and water bridges, leading to a three-dimensional polymeric network.