Vanadium oxydichloride

Vanadium Oxydichloride, V02C12.8H20.—By the action of dilute aqueous hydrochloric acid on the two isomeric hydrates of hypo-vanadic acid, two isomeric forms of this compound have been prepared. The green hydrate gives rise to deep green crystals, and the rose hydrate to blue crystals of the same empirical composition.2 Their constitutions are a matter of doubt.3... 

In the vanadyl systems the species existing in PDC-solutions appear to have distorted octahedral structures . The highest chloride-coordinated ion is [VOCU] -, which may be present to some extent in the absence of excess chloride ions, due to some degree of autocomplex formation by vanadium oxydichloride . Likewise the ultimate azidocomplex seems to have the composition [VO(N3)4]2-. It has been concluded from the spectra that all vanadyl species in propanediol-1,2-carbonate are of lower symmetries than the corresponding species in acetonitrile or in dimethyl sulphoxide, and this has been ascribed to stronger 7r-bonding contributions to the V = 0 bond in propanediol-1,2-carbonate . 

Haszeldine et al. [478] studied the effect of vanadium compounds together with zinc and aluminum alkyls in tetrahydrofuran (THF). The most satisfactory modified Ziegler-Natta catalyst system is obtained when vanadium oxytrichloride and triisobutyl aluminum react together in the presence of an excess THF. The initiation mechanism and the structure of the active complexes is studied in a further publication of Haszeldine. The results demonstrate that the active centers in the catalyst system VOCl3/Al(iBu)3/THF are formed by interaction of vanadium oxydichloride tetrahydrofuranate and triisobutylalu-minum in the presence of THF ... 

---