T-Butyl chromate

The allylic oxidation with derivatives of chromic add (K.B. Wiberg, 1965 H.G. Bosche, 1975), e.g. di-t-butyl chromate (K. Fujita, 1961), CrOj/pyridine (W.G. Dauben, 1969), or KjCr04 (C.Y. Cuilleron, 1970), gives similar products in occasionally very high yields. 

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

Oxidation with chromium(VI) oxide, t-butyl chromate or chromyl chloride may also take place at the allylic position with the formation of unsaturated ketones. The alkene may enhance the rate of displacement of an allylic halide, and the reaction may even take place with the participation of the double bond, so leading to an allylic rearrangement (Scheme 3.25). 

The spiro-ether (tetrahydrofuran) (57) is oxidized by t-butyl chromate to give the spiro-lactone (58). ... 

Wittig salt (51). Wittig reaction with the C14 dialdehyde (52) gave racemic (27). The 3-hydroxy-p-ring system was also obtained from a-ionone (53). Oxidation with t-butyl chromate gave the ketone (54), which with ethanediol underwent double-bond migration to give (55), which was hydrolysed in the presence of... 

This result was independent of the type of chromium compound impregnated, provided the impregnation was done anhydrously. Some examples are dicumene chromium (0) in hexane, chromium (III) octo-ate in toluene, Cr03 in CH3CN, di-t-butyl chromate in hexane, or... 

Metabolite C was first recognised by metabolic studies using [2- C]abscisic acid synthesised in the normal way from [2- C]bromoacetic ester. t-Butyl chromate oxidation of a-ionone provides an efficient synthesis of abscisic acid (Scheme 3). A large number of compounds related to abscisic acid have been synthesised to check their biological activity. In general, conventional synthetic methods were used. The Reformatsky reaction may be used as an alternative to the Wittig reaction for the synthesis of a-ionylidene acetic ester. 

Oxidation of the 3,5-enol chloride of 19-nortestosterone acetate with t-butyl chromate followed by catalytic reduction provides an alternative route to 17j -acetoxyoestr-5-en-7-one and nitration of the 3,5-enol ether with tetranitro-... 

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

The carane ring is cleaved by different reagents in different ways, and many examples appear annually cf. Vol. 1, p. 47 Vol. 2, p. 56). The reaction with t-butyl chromate leads to fairly indiscriminate opening it has been re-investigated, and whereas in benzene the main products are the carenone (400) and the dione... 

Synonyms Bis (1,1-dimethylethyl) ester chromic acid Chromic acid bis (1,1-dimethylethyl) ester Chromic acid di-t-butyl ester Di-t-butoxychromyl Di-t-butyl chromate Di-t-butyl ester chromic acid Empirical C8HisCr04... 

Dibutyi Ceilosolve phthaiate. See Dibutoxyethyi phthaiate 2,4-Di-t-butyl-6-(5-chloro-2H-benzotriazol-2-yl) phenol. See 2-(3, 5 -Di-t-butyl-2 -hydroxyphenyl)-5-chlorobenzotriazole Di-t-butyl chromate. See t-Butyl chromate 2,6-Di-t-butyl-p-cresol. See BHT Di-(4-t-butylcyclohexyl) peroxydicarbonate CAS 15520-11-3... 

Behenalkonium chloride Behenamide N-Benzyldimethylamine Benzyl sulfide Bis-hexamethylenetriamine Butyl acid phosphate n-Butylamine 4-t-Butylbenzoic acid t-Butyl chromate Calcium acetate... 

Barium peroxide t-Butyl chromate t-Butyl hydroperoxide Calcium chromate Calcium hypochlorite... 

Di-t-butyidichlorosilane C8H-i8Cl2Sn Dibutyltin dichloride C8H-i8Cr04 t-Butyl chromate... 

Di-t-butyl chromate and its pyridine adduct are suitable for large-scale oxidations of alcohols to ketones, thus cyclododecanol was converted into cyclododecanone (97 Alcohols are easily separated from non-hydroxylic compounds via their calcium chloride complexes. This method was used to separate cyclododecanone and cyclododecanol and is suitable for the separation of large quantities of material." All-cis-cyclododecane-l,5,9-triol was converted into the all-cis-tri-amine by tosylation, azide substitution, and reduction, and the amine acylated with 2,3-dimethoxybenzoyl chloride to give the tri-amide, an analogue of enterochelin. ... 

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