Nomenclature
CAS number: 14977-61-8
Dichlorodioxochromium; chromium dioxychloride.
Cl
2CrO
2; mol wt 154.90.
Cl 45.78%, Cr 33.57%, O 20.66%.
CrO
2Cl
2.
Description and references
Prepn from CrO3 + HCl: Sisler, Inorg. Synth. 2, 205 (1946); Hein,
Herzog in Handbook of Preparative Inorganic
Chemistry Vol. 2, G. Brauer, Ed. (Academic
Press, New York, 2nd ed., 1965) p 1384; and AlCl3: Flesch,
Svec, J. Am. Chem. Soc. 80, 3189 (1958); from Cr2O3 and TiCl4: Braos, Cohen, US 3111380 (1963 to Natl. Distillers & Chem.). Review
of chromium halides: Fergusson in Halogen
Chemistry Vol. 3, V. Gutmann, Ed. (Academic
Press, New York, 1967) pp 227-302.
Properties
Deep red liquid; appears black under reflected
light. Fumes in moist air. Handle only in
well-ventilated hood. mp -96.5°; bp 117°; d425 1.91. Slightly less viscous than water. Nonconductor
of electricity. Strong oxidizing agent; can react explosively
with combustible organic and inorganic substances. Hydrolyzes
vigorously on contact with water. Reacts vigorously with liquid or
gaseous ammonia. Sol in CCl4, CS2, benzene,
nitrobenzene, CHCl3, POCl3. Its soln in CCl4 is fairly stable. Liquid CrO2Cl2 is
stable indefinitely in glass, aluminum, stainless steel containers
if protected from light and moisture. CrO2Cl2 dissolves CrO3, yielding a powerful oxidant.Caution
Potential symptoms of overexposure
are irritation of eyes, skin, upper respiratory system; eye, skin
burns. See NIOSH Pocket Guide
to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 72.Use
Catalyst for polymerization of olefins; oxidation
of hydrocarbons; in the Etard reaction for production of aldehydes
and ketones; in the prepn of various coordination complexes of Cr.