An unusual open cubane structure in a μ1,1-azido- and alkoxo-bridged tetranuclear copper(II) complex, [Cu4L2(μ1,1-N3)2]•5H2O (H3L = N,N′-(2-hydroxylpropane-1,3-diyl)bis-salicylideneimine)

A new end-on (EO) azido-bridged tetranuclear copper(II) complex [Cu4L2(mu(1,1)-N-3)(2)](.)5H(2)O derived from the ligand H3L (N,N'-(2-hydroxylpropane-1,3-diyl)bis-salicylideneimine) has been synthesized. Its X-ray structure shows an unusual Cu4O2N2 open cubane core in which four copper(II) atoms are connected two by two through two mu(1,1)-azido species and three by three through two alkoxo bridges. The magnetic susceptibility data is dominated by strong antiferromagnetic interactions associated with the alkoxides and weak ferromagnetic interactions arising from the azides, in agreement with magneto-structural correlations found in the literature relative to such bridges in Cu(II) complexes.