Tetrachlorobis triphenylphosphine oxide cerium IV

To a solution of dihydrogen hexachlorocerate(IV), prepared from (1.1 g, 2.0 mmoles) of (NH4)2[ N03)6], in 10 mL of dry methanol, is added a solution of triphenylphosphine oxide (1.1 g, 4.0 mmoles) in 5 mL of dry methanol. A stream of dry hydrogen chloride gas is bubbled through diis reaction mixture at - 20° for a half hour. The cerium(IV) complex precipitates, and the orange product is filtered and is washed with dry methanol and petroleum ether. Anal. Calcd. for CeCl4 2 OPPhj Ce, 16.72 Q, 16.92 P, 7.32. Found Ce, 16.71 Cl, 16.70 P, 7.19. 

To a warm solution of 2,2 -bipyridine l,l -dioxide (1.6 g, 9.3 mmoles) in 20 mL of water is added ammonium hexanitratocerate(IV) (1.1 g, 3.95 mmoles). The reaction mixture is kept at approximately 95° in a water bath for a half hour. Then an excess of NILlPFel is added to effect precipitation of the complex as a yellow-orange crystalline solid, which is washed with ethanol and dried. Anal. Calcd. for [Ce(bpy02)4l[PF6]4 C, 32.63 H, 2.19 N, 7.61 P, 8.41. Found C, 32.08 H, 1.99 N, 7.70 P, 7.94. 

Inorganic Syntheses, Volume 23 Edited by Stanley Kirschner 1985 by Inorganic Syntheses, Inc. 

HEXAKIS(DIPHENYLPHOSPfflNIC AMIDE)LANTHANOID(III) HEXAFLUORO PHOSPHATES, 

Submitted by G. VICENTINIt and L. B. ZlNNERt Checked by S. C. KGOt and L. THOMPSON4  

The hexafluorophosphate ion has proved to be very useful for studies with complexes, since the [PF6] anion has a very weak coordinating ability.1 Lan-thanoid hexafluorophosphates can be obtained in very concentrated aqueous solutions by reaction of a freshly prepared solutions of hexafluorophosphoric acid and a hydrated lanthanoid basic carbonate.2 The resulting solution, after filtration, is evaporated to near dryness. Attempts to isolate the hydrated salts are unsuccessful because of decomposition accompanied by hydrogen fluoride evolution. Nevertheless, the complexes containing diphenylphosphinic amide are isolable and are quite stable.3 

The lanthanoid basic carbonate is obtained by boiling a dilute lanthanoid chloride solution with urea.4 The dilute solution of freshly prepared hexafluorophosphoric acid is obtained by percolating a solution, containing 3.0 x 10-3 mole of ammonium hexafluorophosphate (Alfa products) in 20 mL of water, through an Amberlite IR — 120 H + column (1cm x 25 cm). The eluted solution is allowed to fall dropwise (—20 drops per minute) onto a suspension of 1 x 10 3 mole of the lanthanoid basic carbonate in 5 mL of water, under constant stirring. The addition of the acid is discontinued when a very small residue of the basic carbonate remained (pH 5 6). The solution is then filtered, the residue washed with two portions of 3 mL of distilled water, and then allowed to evaporate at —30° to near dryness, using a flash evaporator and reduced pressure (—20 torr). It is necessary to evaporate carefully to a very small volume, because the solution decomposes, becoming acid and turbid. (This is a very critical point.) 

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