Lead trifluoroacetate alkane oxidation

As Hodges and Garnetthad found in the case of arenes, the addition of PtCl " leads to net oxidation to give chloro-arenes or -alkanes, with reduction of Pt(IV) to Pt(II) Methane was converted to MeCH Once again, a 1°>2°>3° selectivity pattern was observed. In CF3CO2H, trifluoroacetate esters were also formed. For cyclohexane, benzene was a major product, perhaps as a result of dehydrochlorination of the chlorocarbon intermediates. 

Peroxytnfluoroacetic acid is used tor numerous oxidations of saturated hydrocarbons and aromatic compounds It oxidizes alkanes, alkanols, and carboxylic acids with formation of hydroxylation products [29] Oxidation of cyclohexane with peroxytnfluoroacetic acid proceeds at room temperature and leads to cyclohexyl trifluoroacetate in 75% yield, 1-octanol under similar conditions gives a mixture of isomeric octanediols in 59% yield, and palmitic acid gives a mixture of hydroxypalmitic acids in 70% yield [29]... 

Iodine(III) tnfluoroacetates (iodine tristrifluoroacetate and lodosobenzene bis-trifluoroacetate) resemble lead(IV), thallium(III) and mercury(II) reagents in their reactions but do not share the undesirable high toxicity typical for the heavy metals Iodine tristrifluoroacetate is a very powerful oxidant that can introduce the trifluoroacetoxy group even into alkanes [60 61] Because branched alkanes react ... 

Lead(IV)277 and silver(III)301 trifluoroacetates in TFA also oxidize alkanes at room temperature to give alkyl trifluoroacetates [see also Section III.D.3 for reactions of alkanes with Pd(II) trifluoroacetate]. The stoichiometric oxidation of cyclohexane to a mixture of cyclohexanol, cyclohexanone, and adipic acid by cobalt(III) perchlorate in aqueous acetonitrile has also been reported.240... 

The alkane carboxylation reactions are typically undertaken in trifluoroacetic acid (TEA) at 80 °C with a V or Re complex catalyst and peroxydisulfate as the oxidant, under a CO atmosphere, and lead to the corresponding carboxylic acids with one more carbon (Scheme 22.4 for the cases of methane and ethane). 

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