The reactivity of co-ordinated acetylacetone. Part I. Oxygen-18 exchange and aquation of trisacetylacetonatochromium(III)

Abstract

Trisacetylacetonatochromium(III) undergoes acid-catalysed aquation to form a bisacetylacetonato-derivative, the rate of aquation showing linear dependence on the Hammett acidity function H₀.

Oxygen-18 exchange between solvent water and free acetylacetone proceeds rapidly in H-perchloric acid, but exchange with acetylacetone co-ordinated to chromium(III) is slow compared with aquation in solutions of the same acidity.

It is inferred that “one-ended dissociation” as found in trisoxalato-complexes does not occur.