R-Butyl chromate

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. ... 

Allylic oxidation of steroids, particularly at the 7-position, has evoked interest over many years. For example, chromium trioxide-acetic acid," sodium dichromate,and r-butyl chromate have all been used in the oxidation of the 5-a-pregnane series e.g. equation 26). 

Allylic oxidation reactions employing chiomium(VI) reagents therefore appear to be very much dependent upon the intrinsic nature of the substrate as to their regiochemical outcome. This is exemplified by the r-butyl chromate allylic oxidation of (+)-3-carene (67 equation 28) where no great preference for either piquet exists. 

Attylic oxidation. r-Butyl chromate was found superior to selenium dioxide or CrOa -Pya for oxidation of the trienone (1) to (2). This reaction was used in a transformation of a-santonin (4) into yomogin (5), ... 

This method was found to be superior to others tested, including selenium dioxide, chromium triox-ide-acetic acid, and r-butyl chromate. 

Related Reagents. Borane-Pyridine Chlorine-Pyridine Copper(II) Sulfate-Pyridine Di-r-butyl Chromate-Pyridine Dimethyl Sulfoxide-Sulfur Trioxide/Pyridine Sulfur Trioxide-Pyridine. 

Oxidation, reagents Barium permanganate. Bismuth trIoxide. Blue tetrazolium. N-Bromo-acetamide. Bromocarbamide. N-Bromoiucclnlmldc. l-Butyl chromate. r-Butyl hypochlorite. r-Butylhydroperoxide. Caro i. acid. Ceric ammonium nitrate. o-Chloranll. m-Chloropei benzoic acid. NChloroauccinlmlde. Chromic Mid In dll. HiSOi, in acetone (Jonee reagent)i... 

Decarboxylation Benzoic anhydride. N-Bromosuccinimide. r-Butylhydroperoxide. r-Butyl-hypoiodite. Copper chromate. Copper powder. Copper salts. Cuprie carbonate. N,N-Di-methylanilrne. N,N-Dimethyl-p-toluidine see Potassium permanganate, reference 32). Lead dioxide. Lead tetraacetate. Lithium iodide dihydrate. Potassium fluoride. Quinoline. Sodium hypochlorite. 

Oxidation, allylic r-Butyl perbenzoate. f-Butyl chromate. Lead tetraacetate-N-Bromosuc-cinimide. Mercuric acetate. Nickel peroxide. Selenium dioxide. i-amines Cr08-Pyridine. 

Figure 13.7.1 Variation of the rate of reduction of chromate (0.2 mM) in the presence of different tetra-alkylammonium hydroxides (R4NOH) at —0.75 V vs. SCE and 25°C. (Me, methyl Et, ethyl Pr, propyl Bu, butyl). [From L. Gierst, J. Tondeur, R. Comelissen, and F. Lamy, J. Electroanal Chem., 10, 397 (1965), with permission.]...

NCrFe09P2C45H3i, Chromate(l—), hydri-dononacarbonyliron-, -nitrido-bis(triphenylphosphorus)(l +), 26 338 NCr03C7H, Chromium, dicarbonyl(r/ -cyclopentadienyl)nitro8yl-, 28 196 NCrOjCjiH, Chromium, tricarbonyl(i -NJV-dimethylbenzenamineK 28 139 NCr09C,oH9, Chromium, (tert-butyl isocyanide)pentacarbonyl-, 28 143 NCrOsCigH,3, Chromium, (benzoyl isocyanide)dicarbonyl(>t -methyl benzoate)-, 26 32... 

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