Proton affinities of alkylanilines

Relatively little is known about the protonation pattern of C-alkyl derivatives. Earlier reports87 pointed out that a number of meta-alkylanilines (m-anisidine and m-toludine) are preferentially ring protonated in the gas phase at equilibrium. 

The effects of the methyl groups, in particular those of two and four substituents on the ring, have also been probed (Table 7). 

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