Chromyl nitrate

Presence of nitric acid or nitrates in chromium trioxide may cause oxidation reactions to accelerate out of control, possibly owing to formation of chromyl nitrate. Samples of the oxides should be tested by melting before use, and those evolving oxides of nitrogen should be discarded [1], A closed container of the pure oxide exploded violently when laid down on its side. This was attributed to unsuspected contamination of the container [2],... 

Chromyl nitrate, Cr02(N03)2, was found by Miyaura and Kochi to be a much better epoxidizing reagent than Cr02Cl2.277 This reaction is solvent dependent. In basic solvents such as DMF or pyridine, epoxide is the major product (equation 100), whereas in an acetone solution alkene ketal, resulting from the addition of acetone to epoxide, is predominantly produced (equation 101). 

Although the literature describes a number of methods for preparing C1O2F2, the above reaction represents a convenient, quantitative, and facile synthesis. Chro-myl fluoride converts hydrocarbons to ketones and organic acids and is unique in providing easy routes to other chromyl compounds for example, chromyl nitrate is easily prepared from Cr02p2 and NaNOj. Previously, it was necessary to prepare and handle N2O5 in order to prepare chromyl nitrate. ... 

Chromium dioxide, 928 Chromium fluoride, 932 Chromium tetrafluoride, 927 Chromium trioxide, 941 Chromyl bromide, 940 Chromyl chloride, 940 Chromyl halides, 933, 935, 938 Chromyl nitrate, 940 Chromyl perchlorate, 940 CitratoteUurates, 303 Cobalt complexes boron ligands, 99 Cobalt(ll) complexes reduction... 

Alkenes, such as (E)- and (Z)-j8-methylstyrene, are converted stereo-specifically by chromyl nitrate to the corresponding epoxides with high selectivites in aprotic media/ Cosolvents (DMF, acetone, pyridine) are required for effective epoxidation. Products derived from a Cr(IV) intermediate are absent suggesting that the active species is oxochromium(V), formed in situ by the prior one-electron oxidation of solvent. 

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