Aniline from methylaniline separation

The graph shows that 2-methylaniline cannot be separated from 3-methyl aniline and that aniline can be separated from the methyl aniline isomers using an eluent concentration of 5 x 10 3 [H+]. The separation of 2-naphthyl amine from 1-naphthyl-amine can be carried out at 8 x 10 3 [H+] in less than 20 minutes. The separation of aniline and 2-methylaniline using 5 x 10 3 [H+] is shown in Figure 3. The concentration of aniline is 5 ppm while the 2-methylaniline is 10 ppm... 

Pure samples are best prepd by the methylation of acetanilide or benzanilide to the N-methyl compds followed by acid hyd. It has been prepd commercially by the action of methyl ale on aniline in an autoclave under press and by the action of methyl amine on halobenzenes. For a summary of prepns see Refs 6 9. It may be separated from aniline and dime thy laniline by treatment of the mixt with benzenesulfonyl chloride. Dimethylamline fails to react and is extd out with dil acid. Aniline forms benzenesulfonanilide which is acidic and is removed by washing with dil base, leaving the N-methylbenzenesulfonanilide. Purified N-methylaniline is obtd by acid hyd (Ref 8). N-Methylaniline is used as an additive to raise the octane no of motor fuels (Ref 6), as a dyestuff intermediate (Ref 3), in the prepn of Tetryl (see below), and in the prepn of Methylcentralite (Encycl, Vol 2, C137-R)... 

Fig. 4 Separation of basic compounds on the alkylpho-sphonate-modified magnesia-zirconia composite column with 35 65 (v/v) methanol-TRIS buffer (5.0 mM TRIS and 50 mM NaCl, pH 10.0) as mobile phase at a flow rate of 1.0 mL/min. 1—Solvent 2—Caffeine 3—Aniline 4—O-toluidine 5— A-methylaniline 6—0-nitroaniline 7— A,A -dimethylaniline 8—P-aminonaphthalene. (From Ref. [25].)...

Repeat the experiment using methylaniline and then dimethyl-aniline. Test the solubility in dilute hydrochloric acid of the substances separated in these two cases by filtration. Write equations for all reactions, and state clearly how the reagent serves to distinguish from one another the three classes of amines. 

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