Crystal structure of di-μ-hydroxido-κ4O:O-bis-[bis(acetylacetonato-κ2O,O')Cobalt(III)]

Abstract

The dinuclear title complex, [Co2(C5H7O2)4(μ-OH)2] or [Co(acac)2(μ-OH)]2, where acac is acetylacetonate, is centrosymmetric with half of the molecule per asymmetric unit. The molecular structure is a dimer of octahedrally coordinated CoIII atoms with four O atoms from two chelating acac ligands and two O atoms from bridging hydroxide ligands. The crystal packing features weak C-H···O interactions between neighboring molecules, leading to the formation of chains normal to the ac plane. The hydroxide H atoms are not involved in hydrogen bonding because of the bulky acac ligands. This is the first crystal structure reported of a dimeric transition metal bis-acac complex with OH- as the bridging group.