Zirconium acetylacetonate 10-hydrate

Zirconium acetylacetonate 10-hydrate effloresces in air and may be completely dehydrated in a vacuum of 0.1 mm. The anhydrous salt sublimes slowly with some decomposition in vacuo at about 140° and melts at 194.5 to 195° with decomposition. The acetylacetonate reacts with alcohol. Its solubility at 25° per liter in other organic solvents is as follows carbon disulfide, 30 g. carbon tetrachloride, 47 g. acetylacetone, 56 g. ethylene dibromide, 44 g. benzene, approximately 200 g. Both the hydrate and the anhydrous compound give a red color with carbon disulfide on standing. This is also true of hafnium acetylacetonate but not of the thorium compound. 

Zirconium acetylacetonate was first prepared by Biltz and Clinch by the reaction of zirconyl nitrate and sodium acetylacetonate in water solution. The compound was crystallized as the 10-hydrate from a slightly acid solution and dehydrated by several crystallizations from alcohol. Von Hevesy and Logstrup later developed a method for the preparation of hafnium acetylacetonate that has been found applicable to the synthesis of the zirconium compound and this forms the basis of the present procedure. 

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