Synthesis of Tris-(hexafluoroacetylacetonato)-Chromium (III)

Abstract

REDUCTION of Cr(VI) in the presence of chelating ligands offers a promising approach to synthesis of Cr(III) chelates in high yield. This principle was used by Aikens and Reilley¹ to devise a rapid chelometric method for determination of chromate. Reduction of chromate with bisulphite in a buffered solution of ethylenediaminetetraacetic acid (EDTA) gave quantitative formation of Cr(III)-EDTA. The quantitative yield of Cr(III) EDTA suggested that this might be the basis of a general method for synthesis of Cr(III) complexes. We have now applied this principle to synthesis of Cr(III) chelates of much lower stability as exemplified by tris-(hexafluoroacetyl-acetonato)-Cr(III).