Di-''tert''-butyl chromate is an alkoxide with the formula CrO₂(OC(CH₃)₃)₂. It is prepared by treatment of ''t''-butanol with chromic anhydride. It forms red crystals at temperatures below –5 °C, above which it melts to give a red oil. The complex, which is diamagnetic, is of fundamental interest as a model for the intermediates in oxidations of alcohols by chromium(VI). This complex is stable because as a t-butyl groups lack beta-hydrogens. This complex and its analogues have tetrahedral geometry at chromium, as established by

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

of its analogues.

Applications

It is used as a precursor to chromium-based catalysts, such as the

Phillips catalyst The Phillips catalyst, or the Phillips supported chromium catalyst, is the catalyst used to produce approximately half of the world's polyethylene. A heterogeneous catalyst, it consists of a chromium oxide supported on silica gel. Polyethylene, ...

, which are employed for the polymerization of ethylene.

Safety

Like other forms of

hexavalent chromium Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is chromium in any chemical compound that contains the element in the +6 oxidation state (thus hexavalent). Virtually all chromium ore is processed via hexavalent chromium, specifically the ...

, di-''tert''-butyl chromate is classified as a potential carcinogen by the United States

National Institute for Occupational Safety and Health The National Institute for Occupational Safety and Health (NIOSH, ) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the C ...

References

{{DEFAULTSORT:Butyl chromate, tert- Chromates Tert-butyl compounds