Synthesis, structure and magnetic characterization of the first azido bridged heterotetranuclear chromium-sodium complex

The first mixed-metal azido bridged complex of Cr(III)–Na(I) has been prepared and its structure is determined. Reaction of chromium(III) chloride and sodium azide with bis-[(E)-N′-(1-(pyridin-2-yl)ethylidene)]carbohydrazide (HL) produced the tetranuclear complex [Cr2Na2(L)2(CH3OH)2(μ-N3)4(N3)2] (1) in good yield. The structure is composed of idealized octahedral [CrIII(N5O)] cores linked to the octahedral [Na(N4O2)] cores by two bridging azide ligands. Magnetic properties and EPR of 1 were also studied.