The Fascinating Acetylacetone Molecule and Its Acetylacetonate Salts
[caption id="attachment_20255" align="alignright" width="400"] Cobalt III Acetylacetonate[/caption] Acetylacetone is the simplest of the β-diketones and supports the phenomenon we call keto-enol tautomerism (see the illustration). Notice that the third carbon atom in the 5-carbon keto chain loans one of its hydrogen atoms in forming the enol tautomer. The freedom to move of this hydrogen atom suggests acetylacetone is a weak acid.1 In effect, the saturated di-ketone becomes an unsaturated di-alcohol. Only instead of two hydrogen atoms, one to each oxygen atom, there is just the one hydrogen atom that must be shared. Preparation Commercially, acetylacetone or H(acac) can be prepared from isopropenyl acetate by heating it in the presence of an appropriate metal catalyst. Dissociation and Reaction Since it is an acid, it can ionize or "disassociate", giving a positive…