SYNTHESIS AND PROPERTIES OF SOME NEW DOUBLE-METAL AROXIDE COMPLEXES

A new series of double-metal aroxocobaltate(II) tetrahydrofurane compl exes of the type [GRAPHICS] (x = o-NO2, o-Cl, o-Br, m-Cl, p-Br, 2,4-di chloro, 2,6-dichloro and 2,4-dimethyl; n = 1,3,4 or 5) was synthesized by the reaction of anhydrous CoBr2 with the sodium salt of the corres ponding phenol (abbreviated as NaOAr) as a monodentate ligand. The blu e violet crystalline and very air-senstive compounds show good solubil ities in some organic solvents, eliminate THF in vacuo at a temperatur e between 80 and 120-degrees-C/0.8 torr to yield the corresponding THF -free complexes. Electronic spectra (VIS and NIR) and magnetic measure ments at 297-degrees-K point to a prefered tetrahedral configuration o f cobalt(II) in these complexes.