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Chromium Trioxide

Other Names:

Chromium(VI) oxide

Chromic anhydride

General Information:


CAS Number: 1333-82-0

Molecular Weight: 99.99 g/mol

Appearance: Red solid

Chemical Formula: CrO3

Melting Point: 196 C

Chromium trioxide (CrO3) is a dark red/orange solid that acts as a strong oxidizing agent. In organic chemistry it is most often associated with Jones oxidation.

Common Uses:

Reagent for the conversion of primary alcohols to carboxylic acids (Jones oxidation)

Procedure excerpt:

To an orange, homogeneous solution of CrO3 (12.4 g, 0.123 mol) in H2O (88.4 mL) at 0 C was added H2SO4 (10.8 mL) dropwise via addition funnel over 30 min . . .

[full procedure]

Reagent (catalytic) for the conversion of primary alcohols to carboxylic acids

Procedure excerpt:

To a suspension of H5IO6 (159 mg, 0.698 mmol) in ACN was added CrO3 (0.6 mg, 0.0061 mmol), and the mixture was stirred at RT for 30 min. The mixture was cooled . . .

[full procedure]


Chromium trioxide (CrO3) is highly toxic, corrosive, and carcinogenic. It is a powerful oxidizer which can ignite some materials on contact.


1) Patent Reference: WO2011017578, page 69, (8.3 MB)

2) Patent Reference: WO2015129926, page 190, (21.5 MB)

3) Wikipedia: Chromium trioxide (link)

4) Chromium(VI) oxide (link)

5) Burke, S. D.; Danheiser, R. L.; Handbook of Reagents for Organic Synthesis, Oxidizing and Reducing Agents