Preparation and characterization of di-(μ2-CH3COO-κ2O:O′)-tetrakis[μ3-methoxo-2,4-pentanedionatometal(II,III)] complexes

Three new complexes with general formula di-(μ2-CH3COO-κ2O:O′)-tetrakis[μ3-methoxo-2,4-pentanedionatometal(II,III)] (M = Co(III); Co(II), Ni(II), Zn(II)), analogues of the previously reported complex di-(μ2-CH3COO-κ2O:O′)-tetrakis[μ3-methoxo-2,4-pentanedionatocobalt(II,III)] ([Co4(acac)4(CH3COO)2(μ3-OCH3)4]), have been prepared and characterized with X-ray crystallography, mass spectrometry and magnetic susceptibility measurements. The complexes show the cubane type structure with two cobalt(III) sites and two divalent sites, in some cases exhibiting partial occupancy. Susceptibility data indicate that the two divalent sites are weakly ferromagnetically coupled in [Co2.5Ni1.5(acac)4(CH3COO)2(μ3-OCH3)4], J = +3.2 cm−1 (H = −2JexS1.S2).

Complexes with general formula [M(III)xM(II)y(acac)4(CH3COO)2(μ3-OCH3)4], in some cases exhibiting partial occupancy the metal sites, have been prepared and the cubane type structures characterized with X-ray crystallography, mass spectrometry and magnetic susceptibility measurements. Susceptibility data indicate weak ferromagnetic coupling for the two divalent sites.Figure optionsDownload as PowerPoint slide