Lead tetraacetate with arylthallium

The 1,1-dimetallic compounds, R2C(SnMe3)ZnBr, were oxidized by dry air at —10 to 0°C in the presence of Me3SiCl to give aldehydes or ketones, R2C=0. In a related indirect method, arylthallium bis(trifluoroacetates) (prepared by 12-21) can be converted to phenols by treatment with lead tetraacetate followed by triphenylphosphine, and then dilute NaOH. Diarylthallium trifluoroacetates undergo the same reaction. ... 

It has been reported previously (147), and will be discussed in detail later, that arylthallium ditrifluoroacetates may be converted in good yield to phenols by treatment with lead tetraacetate in trifluoroacetic acid solution followed by addition of 1 mole of triphenylphosphine. The immediate product of the above reaction, an aryl trifluoroacetate, is hydrolyzed... 

Synthesis of phenols and aromatic nitriles.3 In a new phenol synthesis, an aromatic hydrocarbon is first thallated with the reagent in trifluoroacetic acid to give an arylthallium ditrifluoroacetate (which can be isolated) and then oxidized with lead tetraacetate in the presence of 1 equivalent of triphenylphosphine. The resulting aryl trifluoroacetate is then hydrolyzed with dilute base. The triphenyl-... 

When an arylthallium compound is treated with the oxidant lead tetraacetate [Pb (OAC) i ] together with triphenyl-phosphine [P(Ph)3], it is oxidized to an aryl trifluoro-acetate. This, when hydrolyzed, yields the phenol after subsequent acidification. To obtain p-cresol by thallation, we would use the following sequence. 

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