Tert-Butyl chromate

Butyl cellosolve, see 2-Butoxyethanol tert-Butyl chromate (as CrOj) n-Butyl glycidyl ether n-Butyl lactate Butyl mercaptan p-tert-Butyltoluene Cadmium, dust and salts (as Cd) Cadmium, fume (as Cd)... 

Butyl cellosolve, see 2-Butoxyethanol tert-Butyl chromate (as CrOj) F (0.8 pm MCEF)... 

Synonyms Bis(tert-butyl)chromate acid, di-tert-butyl ester... 

Toxicology. tert-Butyl chromate is expected to cause irritation of the eyes, nose, and skin. 

Skin contact with tert-butyl chromate caused necrosis of the skin and death of rats. In another report exposed rats had an increase in respiratory rate and signs of mild narcosis. rCT r-Butyl chromate is considered to be an inferred carcinogen because it is a hexavalent chromium compound. ... 

US Department of Health and Human Services (NIOSH) Occupational Safely and Health Guidelines for Chemical Hazards-Supplement IV-OHG (Pub No 95-121), pp 1-8. Occupational safety and health guideline for tert-butyl chromate. Cincinnati, OH, 1995... 

BUTYL CELL0S0L T ACETATE see BPMOOO n-BUTYL CHLORIDE see BQQ750 BUTYL CHLORIDE pOT) see BQQ750 sec-BUTYL CHLORIDE see CEU250 tert-BUTYL CHLORIDE see BQROOO tert-BUTYL CHLOROACETATE see BQRIOO a-BUTYL-a(4-CHLOROPHENYL)-lH-l,2,4-THIAZOLE-l-PROPANENITRILE see MRW775 tert-BUTYL CHROMATE see BQVOOO... 

Other oxidants of hexavalent chromium are chromyl chloride and di-/er/-butyl chromate. Chromyl chloride adsorbed on alumina-silica gel from its solution in dichloromethane oxidizes aliphatic and aromatic alcohols at room temperature within hours in 77-100% yields [675]. Di-tert-butyl chromate, prepared in situ from chromyl chloride in tert-butyl alcohol at -70 °C, gives comparable results under similar conditions [674. Di-tert-butyl chromate, prepared from chromium trioxide and tert-butyl alcohol, oxidizes primary aliphatic and aromatic alcohols to the corresponding aldehydes even at low temperatures (1-2 °C) [677, 678]. 

V./V -Di-Zert-butyl-zV. V -bisitrimcthylsilyl)diaminophosphcnc. 3675 Di-tert-butyl chromate, 3066... 

Chromyl perchlorate, 4055 Cobalt(ll) nitrate, 4215 Di-tert-butyl chromate, 3066 Dichlorine oxide, 4095... 

An interesting variation of the chromic acid oxidation of alcohols to aldehydes was discovered by Oppenauer and Oberrauch.411 When dissolved in tert-butyl alcohol and an organic solvent, alcohols are dehydrogenated to aldehydes by tert-butyl chromate in 90% yield. Experimental details are given in Houben-Weyl s reference work.ln... 

SYNONYMS bis (tert-butyl) chromate, chromic acid bis (1,1-dimethylethyl) ester, di-tert-butyl ester of chromic acid, t-butyl chromate. 

Scheme 36) was used as the starting material. Treatment of this compound with PCC gave diketone 294, along with its regioisomer 415, in variable yields (26-40%). Although this yield is similar to others reported previously in methods using tert-butyl chromate, this method allowed the recovery and recycling of unreacted 291. 

The NIOSH REL (10-hour TWA) is 0.001 mg Cr(VI)/m for all hexavalent chromium [Cr(VI)] compounds. NIOSH considers all Cr(VI) compounds (including chromic acid, tert-butyl chromate, zine ehromate, and chromyl chloride) to be potential occupational carcinogens. The NIOSH REL (8-hour TWA) is 0.5 mg Cr/m for chromium metal and chromium(II) and chromium(III) compounds. 

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