CA abstract: The term "trivanadates" is proposed for the "metavanadates," which have been shown to have the general formula M3V3O9. The following
esters were prepd. by heating the V2O5 with various alcs.; the products were colorless or yellow, and mol. wt. detns. showed the simple formulas. The
alc. solns. of all were yellow when cold, or quickly became yellow, but colorless when hot; the color change is explained by the soln. containing both
reddish yellow hexavanadic esters and colorless trivanadic esters, the equil. between which was displaced toward the colorless compds. as the temp.
was raised; cond. measurements supported this conclusion. Ethyl orthovanadate, Et3VO4, was obtained by boiling V2O5 with abs. EtOH under a reflux
condenser for 6-8 hrs., filtering and concg. at reduced pressure; product clear yellow liquid, b26 108, d15 1.167, sol. in EtOH, C6H6 and C7H8,
solidifies in liquid air to white cryst. mass, decompd. by heating much above 100; addition of 96% EtOH pptd. Et3V3O9, addition of H2O gave a gel,
which formed a deep red colloidal soln. on heating with H2O. When heated to 160-170, Et2O, acetone and some ester volatilized, and a compound,
V4C16H40O13, was formed, dark green cryst. powder, stable in air, insol. in H2O, dil. acid and alkali, sol. in most organic solvents, could be
recrystd. from Et2O and C6H6, decompd. on heating. Propyl orthovanadate, light yellow liquid, d15 1.088, b24 143, properties similar to above;
n-butyl orthovanadate, b22 175, isobutyl orthovanadate, d15 1.033, b16 149; tertiary butyl orthovanadate, colorless crystals, m. 45-7, b15 117, easily
sol. in organic solvents; isoamyl orthovanadate, light yellow cryst., difficult to free from C5H11OH, m. 70, b18 185-7; tertiary amyl orthovanadate,
colorless liquid, d15 0.993, b19 161, b760 206 (decomp.); were also prepd. An attempt to prepare an ester of pyrovanadic acid from Ag4V2O7 in the
above manner gave an ortho compd. Ethyl trivanadate, Et3V3O9, was prepd. by boiling V2O5 with abs.
EtOH for 4-6 hrs., filtering, and evapg. in a vacuum desiccator or by concg. by evapg. the EtOH and cooling on ice; product light yellow powder
decomp. on heating, changed to hexavanadate, then to V2O5 by H2O. Propyl trivanadate and isoamyl trivanadate, light yellow powders, were also formed.
Diethyl monochloro-orthovanadate, (EtO)2VOCl, dark red liquid, d15 1.336, decompd. by light or heating, was obtained from VOCl3 and NaOEt; ethyl
dichloro-orthovanadate, EtOVOCl2, red liquid, b49.5 102, was obtained in a similar manner. MeOH dissolved V2O5 on boiling, but no compd. could be
isolated; glycerol and BzOH dissolved V2O5 but were oxidized on heating. Esters of hexavanadic acid could not be prepd.; they are products of the
action of H2O on the ortho- and trivanadates, and attempts to prep. them resulted in mixts. of tri- and hexavanadates with colloidal V2O5. Aniline
hexavanadate, (C6H5NH3)4V4O172H2O, was prepd. in reddish brown glittering monoclinic prisms (cryst. data given) by mixing a soln. of V2O5 in dil. NaOH
soln. and aniline-HCl soln.; product sol. H2O, insol. EtOH, Et2O, C6H6, slightly sol. in phenol. An ether addition product of vanadium oxydichloride,
VOCl2.2Et2O.2H2O, was prepd. by the action of Na on a mixt. of VCl4 and PhBr as deep blue deliquescent needles, decompd. on heating.
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