Vanadium(V) oxytrinitrate, VO(NO₃)₃. A powerful reagent for the nitration of aromatic compounds at room temperature under non-acidic conditions

Abstract

Vanadium(V) oxytrinitrate is an easy to handle reagent which can be used to nitrate a range of substituted aromatic compounds in dichloromethane at room temperature, leading to >99% yields of nitration products in most cases.

References

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9. Vanadium(V) oxytrinitrate was produced from the reaction of vanadium pentoxide with dinitrogen pentoxide using a modification of the procedure described by Schmeisser: M. Schmeisser, Angew. Chem., 1955, 67, 493 The dinitrogen pentoxide was most conveniently prepared by the dehydration of white fuming nitric acid with phosphorus pentoxide at 50 °C in the presence of a slow stream of ozone cf. N. S. Gruenhut, M. Goldfrank, M. L. Cushing and G. V. Caesar, Inorg. Synth., 1950, 3, 78.
10. (a) The vanadium(V) oxytrinitrate, like all other nitrates, is moisture sensitive and it was stored and handled in a dry nitrogen filled glovebox containing 3 Å molecular sieves or in vacuo on a standard vacuum manifold. The reagent can be stored at room temperature in a glovebox for long periods of time. Slow decomposition occurs at temperatures above 80 °C but beyond this we have no information regarding the thermal stability of VO(NO₃)₃. We therefore recommendCAUTIONwith respect to the use and storage of vanadium oxytrinitrate; (b) although CH₂Cl₂ was used as solvent in all the studies described, vanadium(V) oxytrinitrate is also soluble in CCl₄, CH₃NO₂, cyclohexane and CFCl₃. With CH₃CN it forms a complex VO(NO₃)₃–CH₃CN which has a low nitrating ability, and other coordinating solvents like ethers, aromatics and amines are not expected to be compatible with the reagent.