Toluene side-chain fluorination

GL 1] [R 4] [P 2] Selectivities of up to 36% at 33% conversion were achieved using acetonitrile as solvent (1.0 fluorine-to-toluene equivalent) [13]. When including multi-fluorinated toluenes and chain-fluorinated toluenes, in addition to the mono-fluorinated toluenes, in the selectivity balance, the value increases to 49%. The remainder is lost in other side reactions such as additions or polymerizations. 

A small amount of side-chain fluorination was observed [274], Benzyl fluoride was formed in about the same extent as the meta isomer. Small amounts of difluoro-toluenes and trifluorotoluenes as well as some unidentified high-boiling compounds were also found [274]. Additional products were not detected [308],... 

The oxidative fluorination of C-H bonds of the side chain in toluene l43 and ethylbenzene derivatives 4 has been reported.45 4fi These alkyl aromatics bearing electronegative substituents are cleanly fluorinated on the alkyl group in liquid hydrogen fluoride in the presence of lead(IV) oxide,45 nickel(IV) oxide,45 silver(II) fluoride,46 cobalt(III) fluoride,46 or cobalt(III) acetate.46... 

This fluorine-containing, oxidation-resistant alcohol is best oxidized by the Pfitzner-Moffatt reaction, using dichloroacetic acid as catalyst. Observe the use of toluene, instead of carcinogenic benzene, as solvent. A Swern oxidation was not reproducible, and caused substantial epimerization of the isobutyl side chain. Collins oxidation was successful, but ... 

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