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Kinetics of the reactions of 1-chloro-2,4,6-trinitrobenzene and phenyl-2,4,6- trinitrophenyl ether with aromatic amines in mixed solvents: Effect of amine basicity on hydrgen-bond interactions in toluene-methanol mixtures

Alice I. Babatunde, Ariyo M. Olusegun and. Chukwuemeka Isanbor

The kinetics of the reactions of 1-chloro-2,4,6-trinitrobenzene, 1, with aniline and N-ethylaniline respectively and that of phenyl-2,4,6-trinitrophenyl ether, 2, with aniline in toluene and toluene-methanol mixtures were studied at different temperatures. The reaction of 1 with the amines are not base-catalysed in toluene and the addition of small amounts of methanol to toluene medium for the reaction of aniline produced a slight diminution in rate up to 0.1% methanol, while methanol contents above 0.1% produced slight rate increase. Continuous moderate rate increase was displayed by N-ethylaniline reaction under the same reaction condition. The rates of both reactions were enhanced by increase in temperature. The reaction of phenyl-2,4,6-trinitrophenyl ether, 2, with aniline was basecatalysed and added methanol produced remarkable rate increase as previously observed for the reaction in benzene-methanol mixtures at 30oC. The reaction displayed negative temperature effect, a reverse of the effect of temperature on the former reactions. The conflicting effects of added methanol and temperature in these reactions were reasonably accommodated by previously proposed cyclic transition state mechanism.