Carboxylate clusters with the M4O4 cubane-like core: pivalate cocrystal containing CoII and NiII

Joint thermolysis of the dinuclear pivalate complexes M-2(mu-H2O)(mu-Piv)(2)(Piv)(2)(HPiv)(4) (M = Co (1) and Ni (2), Piv(-) is the pivalate anion), in decane at 174 A degrees C at the reactant ratio 1: 1 followed by treatment of the dry thermolysis product with methanol afforded crystals of a new cocrystallization product of the molecules containing the heterometallic cubane-like core M-4(Co,Ni)O-4. According to the X-ray diffraction data and the results of magnetic measurements, inductively coupled plasma atomic emission spectrometry (ICP-AES), and investigations of the solid-state thermal decomposition products, the isolated cocrystallization product has the general formula [Co1.6Ni2.4(mu(3)-OMe)(4)(mu(2)-Piv)(2)(pg(2) -Piv)(2)(MeOH)(4)] center dot 4MeOH (3 center dot 4MeOH). Thermolysis of the crystals of the solvate 3 center dot 4MeOH is a destructive process accompanied by the intramolecular redox reaction. A mixture of metallic Ni and cobalt oxide (CoO) are the final solid decomposition products of 3 center dot 4MeOH in an argon atmosphere, whereas a mixture of the phases NiO, Co3O4, and NiCo2O4 is formed in air.