Chromium(VI) oxide

• Catalog No.: 12522
• CAS Number: 1333-82-0
• M. F.: CrO3
• M. W.: 99.9943
• Purity: 99%

SYNONYMS

• Title: 三氧化铬(VI)
• IUPAC name: λ^6-chromium(6+) ion trioxidandiide
• IUPAC Traditional name: λ^6-chromium(6+) ion trioxidandiide

DATABASE IDS

• EC Number: 215-607-8
• CAS Number: 1333-82-0
• Merck Index: 142235
• MDL Number: MFCD00010952

PROPERTIES

• Purity: 99%
• Apperance: Crystalline
• Boiling Point: 250°C dec.
• Density: 2.7
• Melting Point: 196°C
• GHS Hazard statements: H271-H301-H310-H330-H317-H334-H340-H350-H372-H361-H314-H318-H400-H410
• European Hazard Symbols: Highly toxic (T+)
• European Hazard Symbols: Oxidising (O)
• European Hazard Symbols: Nature polluting (N)
• GHS Precautionary statements: P221-P283-P301+P310-P303+P361+P353-P304+P340-P305+P351+P338-P320-P330-P361-P405-P501A
• Risk Statements: 45-46-9-24/25-26-35-42/43-48/23-62-50/53
• RTECS: GB6650000
• Safety Statements: 53-45-60-61
• Storage Warning: Hygroscopic
• TSCA Listed: 是
• Hazard Class: 5.1
• UN Number: UN1463
• Packing Group: II

REFERENCES

• Numerous examples of oxidations with this reagent are to be found in Organic Syntheses. For directions for preparation of chromic acid (Jones) reagent, see: Org. Synth. Coll., 5, 866 (1973).
• For preparation of alumina-supported reagent, and use in chemoselective oxidation, for example of allylic alcohols, see: Synth. Commun., 24, 1823 (1994). For selective oxidation of aliphatic alcohols to aldehydes in ether/water, see: Chem. Ind. (London), 312 (1989). Has also been used catalytically in the presence of a co-oxidant, see Sodium perborate tetrahydrate, A10189, and Periodic acid, B20433.
• Several CrO₃ based reagents have been developed, usually with the objective of increasing selectivity, of which CrO₃:(Pyridine)₂ (Collins' reagent) is probably the most widely used. For a procedure, see: Org. Synth. Coll., 6, 644 (1988). However, to control the highly exothermic reaction (possible fire hazard!), the reagent is probably best prepared and used in situ in dichloromethane: J. Org. Chem., 35, 4000 (1970); Org. Synth. Coll., 6, 373 (1988);or acetonitrile: J. Org. Chem., 45, 1135, 1142 (1980). The use of Celite. as a support for the reagent has been found to be beneficial: same ref. and: Synth. Commun., 3, 115 (1973); Tetrahedron Lett., 2079 (1973). See also Pyridinium chlorochromate, A11752, 2,2'-Bipyridine, A15782, 3,5-Dimethyl-1H-pyrazole, A10157, and Potassium chlorochromate, A19000.