Inorganic Syntheses, Volume V
Edited by Therald Moeller
Copyright © 1957 by McGraw-Hill Book Company, Inc.
VANADIUM(ZV) OXY(ACETYLACET0NATE)
113
35. J. F. STEINBACH
and F. FREISER:Anal. Chem., 26, 881 (1953): 26,375
(1954).
36. A. JOBand P. GOISSEDET:
Compt. rend., 167, 50 (1913).
and E. BACKER:ilionatsh., 49, 401 (1928).
37. F. FEIGL
38. G. Jantsch and E. hIEYER: Ber., 63B, 1577 (1920).
39. E. KUROWSKI:
ibid., 43, 1078 (1910).
40. R. C. MENZIES:J. Chem. SOC.,1934, 1755.
41. G. T. MORGAN
and R. A. S. CASTELL:
ibid., 1928, 3252.
42. A. ROSENHEIM
and A. BERTHEIM:
2.anorg. Chem., 34, 425 (1903).
43. G. URBAIN: Bull. soc. chim. Paris, [3] 16, 347 (1896).
CORP.,LTD.,and S. COFFEY:
British patent 289,493
44. BRITISHDYESTUFF
(Oct. 28, 1926); cj. C. A., 23, 606 (1929).
and F. h l . BREWER:
J. Chem. SOC.,127, 2379 (1925).
45. N. V. SIDGWICK
46. A. COMBES:Compt. rend., 106,868 (1887).
47. B. CIOCCA:
Gazz. chim. ituZ., 67, 346 (1937).
48. F. GACK:Monatsh., 21, 98 (1900).
49. W. BILTZand J. A. CLINCH:2. anorg. Chem., 40, 218 (1904).
50. W. S. FYFE:Anal. Chem., 23, 174 (1951).
51. G. H. CARTLEDGE:
U.S. patent 2,556,316 (June 12, 1951); cf. C. A., 46,
1585 (1952).
52. A. COMBES:Compt. rend., 119, 1221 (1894).
53. A. CONBES:ibid., 108, 405 (1889).
Bull. soc. chim. France, 131 1, 345 (1889).
54. A. COMBES:
55. G. T. MORGAN
and H. D. K. DREW:J. Chem. SOC.,119, 1058 (1921).
56. C. C H A B Rand
I ~ E. RENGADE:
Compt. rend., 131, 1300 (1900); 132, 472
(1901).
J . Chem. SOC.,1932,2694.
57. T. S. MOOREand M. W. YOUNG:
58. J. E. BLANCH:
master's dissertation, The Pennsylvania State University,
1956.
30. VANADIUM (IV) OXY (ACETYLACETONATE)
pis (2,4-pentanediono)oxovanadium(IV)]
Vanadium(1V) oxy(acety1acetonate) has been prepared
by direct reaction of acetylacetone (2,4-pentanedione)
with either hydrous vanadium(1V) oxide or an aqueous
Procedure A is
solution of an oxovanadium(1V)
an adaptation of this approach. The facts that acetylacetone can reduce vanadium(V) oxide to vanadium(1V)
oxide, react as an acid4g5with the latter to give the desired
product, and behave as a solvent for that product are
combined in procedure B to give a synthesis based directly
upon readily available starting materials.
114
INORGANIC SYNTHESES
Procedure A
Preparation from Vanadium(V) Oxide through Prior
Reduction to Oxovanadium(1V) Ion
+ 2HzSO4 + CzHsOH 2VOSO4 + 3Hz0
+ CHiCHO
voso4+ 2C5HsOZ+ N a 2 C 0 3 4 VO(CsH70z)z+ Na2S04
VzOs
4
+ HzO + COz
SUBMITTED
B Y RICHARD
A. ROWE*A N D MARKM. JONES*
CHECKED
BY PETERBLocxt
T o 20 g. of pure vanadium(V) oxide (0.11 mol) in a 1-1.
beaker are added 50 ml. of distilled water, 35 ml. of 96%
(by weight) sulfuric acid, and 100 ml. of ethanol. The
mixture is heated to boiling on a hot plate or steam bath
and stirred. As the reaction proceeds, the initial slurry
of vanadium(V) oxide darkens, becomes light green, and
finally turns dark blue. The solution of vanadium(V)
oxide and its reduction to vanadium(1V) are complete in
30 minutes. The solution is filtered and the filtrate
returned to the 1-1. beaker. Then 50 ml. of freshly distilled acetylacetone (ca. 0.49 mol) is added, and the solution
is neutralized by ad ng a solution of 80 g. of anhydrous
sodium carbonate d' solved in 500 ml. of distilled water.
The sodium carbonate solution is added slowly with continuous stirring to avoid excessive frothing.$ The precipitated product is removed by filtration on a Buchner
funnel and dried by drawing air through the filter cake.
The yield of crude vanadium(1V) oxy(acety1acetonate) is
48 t o 53 g. [75 to 83%, based upon vanadium(V) oxide
used]. The product is recrystallized from chloroform.
P
* University of
Illinois, Urbana, Ill.
t The Pennsylvania State University, University Park, Pa.
# The reaction is conveniently followed with a pH meter, precipitation
beginning at pH 3.5 and being complete at pH 5.5. At the end point,
addition of more sodium carbonate solution causes no more frothing.
115
VANADZUM(ZV) O X Y ( A C E T Y L A C E T 0 N A T E )
Anal. Calcd. for VO(C5H70z)2:
C, 45.28; H , 5.28; V, 19.25.
Found: C, 45.1; H, 5.37; V, 19.2.*
Procedure B
Direct Preparation from Vanadium(V) Oxide
2Vz05
+ 9CsHsOz
4
4VO(CsH70z)z
+ (CH&O)&O
w. C O N A R D F E R N E L I U S t
SUBMITTED BY BURLE. R R Y A N T t A N D
CHECKED
B Y DARYLE
H. B U S C H R.
,~
STRATTON
1
+ 5Hz0
CARLSTOUFER,~
A N D WILMER
Five grams of technical vanadium(V) oxide (ca. 0.03
mol)§ is placed in a 200-ml. round-bottomed flask which is
attached to a reflus condenser through a ground-glass
joint. One hundred milliliters of commercial acetylacetone
(ca. 0.98 mol)j/ is added, and the mixture is reflused gently
for 24 hours. The suspension is filtered while hot,l/ and
the filtrate is cooled. About 5 g. of product separates as
tiny blue crystals. The remaining acetylacetone is removed
by evaporation in a stream of air. The solid product is
washed with acetone and ethyl ether and dried a t 110".
The yield is 10 g. (68%). Anal. Calcd. for VO(C5H,02)z:
C, 45.28; H, 5.28; V, 19.25. Found: C, 45.09;** H, 5.33;**
* Vanadium is determined by destroying the organic material with sulfuric
acid and igniting to vanadium(V) oxide.0
t The Pennsylvania State University, University Park, Pa.
$ The Ohio State University, Columbus, Ohio.
Q The reaction apparently proceeds without difficulty with any quantity
of vanadium(V) oxide if the specified ratio of reactants is maintained.
Larger ratios of vanadium(V) oxide give large crystals or crystal aggregates
of product in the reaction flask because the solubility of the product is
exceeded. Vanadium (V) oxide prepared by decomposition of pure ammonium metavanadate at 250" gives higher yields of product b u t no increase in
its purity.
11 If the material is colored, it should be distilled before being used.
7 Resinous material may form and clog the filter. The addition of a small
quantity of acetone before filtration alleviates this difficulty. The nature
of the organic oxidation product is indefinite and is represented in a n idealized fashion in the equation as (CH&O)&O.
** Data supplied by the checkers.
116
INORGANIC SYNTHESES
V, 19.32. iMateria1 of analytical-reagent purity is obtained
by recrystallization from acetone or acetylacetone, with a
recovery of 50 to 80%.
Properties
Vanadium(1V) oxy(acety1acetonate) is a blue to bluegreen compound, crystallizing in the monoclinic system
with refractive indexes of a, 1.520; p, 1.676; y, 1.739.’
The compound was originally believed to be a 1-hydrate
but is now known to be anhydrous. It forms addition
compounds with pyridine, methylamine, and other amines.8
Vanadium(1V) oxy(acety1acetonate) decomposes at elevated temperatures and has no definite melting point.
The compound is soluble in ethanol, benzene, chloroform,
and acetylacetone but is only moderately soluble in acetone
or ethyl ether.
References
1. A. GUYARD:
BuU. soc. chim. Paris, 121 26, 350 (1876).
2. G. T.MORGAN
and H. W. Moss: J. Chem. Soc., 103, 78 (1913).
3. A. ROSENHEIM
and H. Y. MONG:2.anorg. u.allgem. Chen~.,148,25 (1925).
4. F. GACH:Mmatsh., 21, 98 (1900).
;i. G. URBAIN
and A. DEBIERNE:
Compt. rend., 129, 302 (1899).
6. J. MEYERand K. HOEHNE:
Mikrochemie, 16, 187 (1034).
7. P. T. B. SHAFFER:
doctoral dissertation, The Pennsylvania State Uni-
versity, 1955.
8. M. hf. JONES:J . Am. a m . Soc., 76, 5995 (1954).