Thorium acetylacetonate

Ammoniates (cont.) of iron(II) bromide, 4 161 nomenclature of, 2 264 of thorium acetylacetonate, 2 125 of thorium bromide, 1 54 See also Am mines)... 

Ammonophosphorous acids, nomenclature of, 2 265 Anatase, formation of, by 7-ti-tanium(IV) oxide, 6 82 Aniline, compound with thorium acetylacetonate, 2 215 5-Anilino-l,2,3,4-thiatriazole, 6 45 Anions, nomenclature of, 2 258 Antimony(III) cesium chloride, 2SbCl3-3CsCl, precipitation in extraction of cesium from pollu-cite, 4 6... 

Case 1. Lower chelates in aqueous phase (hydroxyl complexes, masking effects, and adducts negligible) Particularly with multivalent metals, an appreciable fraction of the metal ion in the aqueous phase may exist as lower complexes. Thus Rydberg, in studying the extraction of thorium acetylacetonate from water... 

Using Rydberg s data for the extraction of thorium acetylacetonate (Example 23-5), calculate the complete extraction curve of E against pH for [HL] =... 

Directions are given for the preparation of the following beryllium acetylacetone (synthesis 5), aluminum"acetylace-tone (synthesis 9), bis[tris(2,4-pentanediono)titanium(IV)] hexachlorotitanate(IV) (synthesis 34), zirconium acetylacetone (synthesis 35), and thorium acetylacetone (synthesis 36). 

Thorium acetylacetonate was first described by Urbain, who synthesized it by the action of an alcoholic solution of acetylacetone on freshly precipitated hydrous thorium oxide and by a metathetical reaction between sodium acetylacetonate and a thorium salt such as thorium nitrate. The crude product was purified by sublimation and by crystallization from chloroform. BUtz, - who subsequently determined the atomic weight of thorium by means of the acetylacetonate, added a solution of acetylacetone in aqueous ammonia to a solution of thorium nitrate and crystallized the precipitate from alcohol. 

To 25 g. of freshly distilled acetylacetone suspended in 50 ml. of water 6 N ammonia is added (drop by drop from a buret), with stirring, until solution is complete. This solution is mixed with one containing 25 g. of thorium nitrate in 200 ml. of water, and 6 N ammonia is added drop by drop until the noixture becomes alkaline to litmus. The precipitated thorium acetylacetonate is removed by filtration, washed, and air-dried. Yield 26 g. 

To recrystallize from toluene 25 g. of thorium acetylacetonate is dissolved in 100 g. of toluene. The small amount of undissolved suspended material is removed by stirring the solution with a few grams of animal charcoal and filtering. The clear, pale-yellow filtrate is cooled to — 78° in a dry ice-acetone bath for several hours. The acetylacetonate separates as a mass of small white crystals, which are filtered in a Buchner funnel previously cooled in powdered dry ice, and washed with a little toluene at —78° m.p. 171.5°. Yield 15 g. (60 per cent). 

Thorium acetylacetonate is insoluble in water and soluble in many organic solvents. It is converted by acids into acetylacetone and the thorium salt of the acid used. Its vapor pressure at 100° is 3.2 + 0.3 X 10 mm. 

The molecular weight of thorium acetylacetonate has been determined in carbon tetrachloride and other organic solvents. According to Biltz it forms an ammoniate [Th(C5H702)4]2-NHs and a similar derivative with aniline, which can be crystallized from ether. 

---