Chromyl acetate

A literature method for preparation of chromyl acetate by interaction of chromium trioxide and acetic anhydride was modified by omission of cooling and agitation. The warm mixture exploded violently when moved [1], A later publication emphasised the need for cooling, and summarised several such previous occurrences [2], An earlier reference attributes the cause of chromium trioxide-acetic anhydride oxidation mixtures going out of control to presence of nitric acid or nitrates in the chromium trioxide, and a simple test to check this point is given [3], Mixtures used as a reagent for the remote oxidation of carboxylic esters are potentially explosive, and must be made up and used at below 25 °C under controlled conditions [4], An attempt to purify the anhydride by warming with 2% w/v of trioxide led to an explosion at 30°C [5],... 

Chlorine dioxide, 4042 Chlorosulfuric acid, 3997 Chloryl perchlorate, 4104 Chromic acid, 4229 Chromium pentafluoride, 4226 Chromium trioxide, 4242 Chromyl acetate, 1494... 

Chlorophenyl isocyanate, 2648 Chlorotetralluorophosphorane, 3987 Chlorotrimethylsilane, 1304 Chromyl acetate, 1494... 

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... 

Alkanes are preferentially hydroxylated at the more nucleophilic C—H bonds, with relative reactivities tertiary secondary primary hydrogens = 7000 110 l.303 This reaction occurs with a high retention of configuration at the hydroxylated carbon atom, as shown by the selective formation of cis-9-decalol from the oxidation of cis-decalin with chromyl acetate in an acidic medium304 and the hydroxylation of chiral (+)-3-methylheptane (91) to chiral alcohol (92) with 72 to 85% retention of configuration.305... 

Inorganic reagents like chromyl chloride, chromyl acetate in carbon tetrachloride,114 as well as peroxytrifluoroacetic acid115,116 are believed to... 

Chlorine dioxide, 4036 Chlorosulfuric acid, 3991 Chloryl perchlorate, 4098 Chromic acid, 4223 Chromium pentafluoride, 4220 Chromium trioxide, 4236 Chromyl acetate, 1490... 

Direct substitution of hydrocarbon 29 via both carbomethyloxynitrene insertion (Eq. (29)) and chromyl acetate oxidation (Eq. (30)) has been studied. The nitrene insertions are fairly unselective. On a per bond basis, both tertiary... 

Possibly this is due to a greater charge development in the transition states of the chromyl acetate oxidations. Solvolysis reactions at the 10-position are known to be highly unfavorable 9S). The solvolytic reactivity of 10-tricyclo [5.2.1.0 4>10] decyl tosylate is retarded relative to 1-adamantyl tosylate by a factor of approximately 106 at 70°C in acetic acid. 

The ketone 629 has been isolated from peony flowers. It had already been synthesized several times for example, by hydroboration of the enamine 630 of the isomeric ketone 627, then Cope elimination of the iV-oxide 631 of the amino alcohol. Chromyl acetate oxidation of 1,8-cineole (553) led first to 629 further oxidation gave diketones. Aspergillus niger also gave some 629, although the main products were the corresponding alcohols. ... 

The oxidation of alkenes with chromyl acetate has been reviewed by Wiberg.6... 

Photocyclization Chromyl acetate. Tetrachloro-cyclopentadienone ethylene ketal. Photocyclophile Dichlorovinylene carbonate. 

Oxidation of the known lactone (191 X = H,H) with CrOa yields (191 X = Chromyl acetate oxidations of exo- and en[Pg.67]

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