Oxidation chromyl chloride

The effect of solvent upon k2 has been reported , and it was concluded that the activated complex is not sufficiently polar to be called ionic . The oxidations of toluene and triphenylmethane exhibit primary kinetic deuterium isotope effects of 2.4 and ca. 4 respectively. No isotopic mixing occurred during formation of the Etard complex from a mixture of normal and deuterated o-nitrotoluene . The chromyl chloride oxidation of a series of substituted diphenylmethanes revealed that electron-withdrawing substituents slow reaction while electronreleasing groups have the opposite effect, the values ofp andp being —2.28 + 0.08 and —2.20 + 0.07 respectively . ... 

Chromyl chloride oxidation of alkenes proceeds via the formation of adducts at a rate necessitating stopped-flow techniques. At 15 °C the formation of 1 1 adduct from styrene and oxidant in CCI4 solution is simple second-order with 2 = 37.0 l.mole .sec . Measurements with substituted styrenes yielded = — 1.99. E = 9.0 kcal.mole and = —23.8eu for styrene itself. Hydrolysis of the styrene adduct yields mostly phenylacetaldehyde (76.5 %)and benzaldehyde (21.1 %). Essentially similar results were obtained with a set of 15 alkenes and... 

Hydratropaldehyde has been prepared by hydrolysis of phenylmethylglycidic ester,2 3 4 by chromyl chloride oxidation of cumene,5 by the elimination of halogen acid or water from halohydrins or glycols,5 8 and by the distillation at ordinary pressure of methylphenylethylene oxide.9,10... 

I n contrast to the relative simplicity of the chromyl chloride oxidation of 2,2-disubstituted-l-alkenes to aldehydes, the rlimmyl acetate and chromic acid oxidations generally lead to epoxides, acids, and carbon-carbon double bond cleavage. For example, chromyl acetate oxidizes 4,4-dimethyl-2-neopentyl-I pentene primarily to l,2-epoxy-4,4-dimethyl-2-neopentyl-pentane in low yield,9 and chromic acid oxidizes the alkene principally to 4,4-dimethyl-2-neopentylpentanoic acid.6,10... 

Similar oxidative rearrangements to produce carbonyl compounds have been carried out with thallium(III) nitrate557 or peroxytrifluoroacetic acid-BF3.558 The Jones reagent (Cr03—H2S04) in the presence of a catalytic amount of Hg(II) is also effective.559 Chromyl chloride oxidation, when combined with reductive workup, is a simple, convenient one-step method to convert 2,2-disubstituted 1-alkenes to aldehydes.560,561... 

K. B. Sharpless, A. Y. Teranishi, J.-E. Backvall, Chromyl chloride oxidations of olefins. Possible role of organometallic intermediates in the oxidations of olefins by oxo transition metal species, J. Am. Chem. Soc. 99 (1977) 3120. 

Chromyl chloride oxidation of tetraphenylethylene (4) results in cyclization to give 9,10-diphenylphenanthrenc (5) in 70% yield.9 The major product of the oxidation of 1,1,2,2-tetraphenylethanol by chromyl chloride is also (5). °... 

Oxidation of styrenes. Freeman et at.1 have examined the chromyl chloride oxidation of the three styrenes (1), (4), and (7). Under conditions employed,... 

Oxidation of the trihydroxypropyl compound 7 or the aldehydes 38 and 40 with chromium trioxide in acetic acid or 50% sulfuric acid furnishes the 3-carboxylic acids, which readily decarboxylate to the 3-unsubstituted compounds at their melting points. " In contrast, the 3-methyl-l-phenyl compoimd is not appreciably attacked by chromiiun trioxide, potassium permanganate, or selenium dioxide. Chromyl chloride oxidation of 7 does not give the aldehyde 38 but apparently provides the tetraflavazolyl ether 41. The inertness of the 3-methyl group is emphasized by its stability toward bromine and its lack of reaction with benzaldehyde." ... 

Sharpless, K. B. Teranishi, A. Y. Backvall, J. E. Chromyl Chloride Oxidations of Olefins. Possible Role of Organometallic Intermediates in the Oxidations of Olefins by Oxo Transition Metal Species. /. Am. Chem. Soc. 1977, 99, 3120-3128. 

The kinetics of the chromyl chloride oxidation of the carbon-carbon double bond of styrene have been examined using stopped-flow spectrophotometry/ the product being a chromyl chloride-styrene adduct. The rate is first order with respect to each reactant and a linear free-energy relationship (Hammett correlation) has been shown to hold for a variety of substituted groups. The data are consistent with a mechanism involving electrophilic attack by the chromium(vi) species on the double bond to yield the adduct, which decomposes on hydrolysis to give phenylacetalde-hyde and benzaldehyde as the major reaction products ... 

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