Ammonium hexanitratocerium

Cycloaddition reactions of nitrile oxides continue to be the source of new isoxazoles and dihydroisoxazoles. The oxidation of a-hydroxyimino acids 1 by ammonium hexanitratocerium(IV) has provided a new method of generation of benzonitrile oxide and other nitrile oxides on the other hand the oxime 2 is simply dehydrogenated by this oxidant to produce benzoylnitrile oxide <99BSJ2277>. Manganese dioxide has also been used to oxidise aldoximes to nitrile oxides the reaction is most efficient with methyl (hydroxyimino)acetate <99TL5605>. ... 

Cerium(IV) Nitrate Test (Ammonium Hexanitratocerium(IV) Test). Dissolve 15 mg of the unknown in a few drops of water or dioxane in a reaction tube. Add to this solution 0.25 mL of the reagent and mix thoroughly. Alcohols cause the reagent to change from yellow to red. 

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