Mono methyl aniline

TEST Aniline 0- toluidine m-> toluidine P-. toluidine I- naphthyl- amine 2- naphthyl- amine mono- methyl- aniline diphenyl- amine dimethyl- aniline triphenyl- amine... 

Mono-methyl aniline, CeHsNH(CHa), or methyl phenyl amine,... 

Rearrangement of Alkyl Anilines.—Both mono-methyl aniline and di-methyl aniline undergo an interesting rearrangement when their salts are heated in sealed tubes to 250°-350°. The mono-methyl aniline yields a mixture of ortho- and para-toluidines while the dimethyl aniline yields first a mixture of ortho- and para-mono-methyl toluidines and then finally from each of these intermediates there is obtained unsymmetrical meta-xylidine only. 

Di-amino derivatives of the secondary amines, mono-methyl aniline, and the tertiary amines, di-methyl aniline, are also known. Of these compounds the para-amino di-methyl aniline is the most important in the dyestuff industry. Tri-amino, tetra-amino, penta-amino and hexa-amino derivatives of benzene and also penta-amino toluene are all known. 

Di-phenyl amine, CeHj—NH—CeHg Cells—NH—CH3, Mono-methyl aniline... 

Methylation of aniline forms a range of products varying from N-alkylated to C-alkylated compounds. ALPOs and substituted ALPOs facilitate N-alkylation whereas ZSM-5 catalyse both C- and N-alkylations. ZSM-5 catalyst forms only mono methylated products. Both mono and di methylated products are formed with SAPOs and ALPOs. KY and CsY catalyse only mono methyl aniline formation. Conversions are high with ZSM-5, KY and CsY. Mechanism of reaction is proposed. 

Then, contrary to our previous hypothesis, the reaction proceeds via a Bai2 displacement of aniline on DMC. The product, mono-A -methyl aniline (PhNHMe), plausibly adsorbs into the zeohte in a different way with respect to anihne, because different H-bonds (N H — O-zeolite) take place with the solid. As recently reported by Su et al., A-methyl amines also may interact with NaY by H-bonding between the protons of the methyl group and the oxygen atoms of the zeolite this probably forces the molecule a bit far from the catalytic surface in a fashion less apt to meet DMC and react with it. This behavior can account for the mono-A-methyl selectivity observed, which is specific to the use of DMC in the presence of alkali metal exchanged faujasites in fact, the bis-A-methylation of primary aromatic amines occurs easily with conventional methylating agents (i.e., dimethyl sulfate). ... 

Figure 21. Conversion of substituted anilines (OT, MT, and PT are respective ortho-, meta-, and para-toluidine, PA = p-anisidine, and PAA = p-aminoacetophenone), corresponding mono-N-methylated anilines selectivity and yield obtained on Cu0.5Zn0.5Fe204 at 300oC with methanol. Only in the case of PAA, feed with CH30H PAA = 6 was employed to avoid solubility problem, and in all other cases a CH30H Sub. Amline H20 = 3 1 1 was maintained. Reprinted from Applied Catalysis A General, 320, Vijayaraj M., et al., 2007, 64-68 with permission from Elsevier.

Als Nukleophile werden primare und sekundare Amine bei der Reaktion mit Diphenyl-methyl-sulfonium-perchlorat in Acetonitril in Gegenwart von festem Kaliumcarbonat N-methyliert. Das Sulfonium-Salz dient bei dieser Zweiphasen-Reaktion gleichzeitig als Pha-sentransfer-Katalysator. Bei Anilin als primarem Amin erfolgt sowohl Mono- als auch Dimethylierung aus N-Methyl-anilin erhalt man in maBigcr Ausbcute N,N-Dimethyl-anilin (57%)4 ... 

Di-methyl aniline, CeHs—N(CH3)2, is a liquid boiling at the same point as the mono-methyl compound with which it is obtained by the ordinary method of preparation and from which it may be separated by the method just described. It forms well crystallized salts, especially the double salt with platinum chloride, viz., CeHs—N(CH3)2.HCL-PtCh. This compound crystalhzes, with two molecules of water, in ruby colored prisms, which, on loss of water, become reddish-yellow plates. The acid oxalate salt, CeHs—N(CH3)2.(COOH)2, forms large rectangular plates melting at 139°. With nitrous acid the reaction is the one characteristic of aromatic tertiary amines. 

Di-methyl aniline also forms a known nitro product, but monomethyl aniline does not. Di-nitro products analogous to the mono-nitro products are known in some cases. 

The constitution of rosaniline as the ortho-mono-methyl homologue of para-rosaniline has been fully established. We thus see that for the preparation of rosaniline both ortho- and />flrfl-toluidine are essential and this has been found to be the fact as neither one alone will yield this dye. The obtaining of both dye compounds in the preparation from crude aniline is explained by the fact that this substance is a mixture of not only aniline and />ara-toluidine but or/ o-toluidine also. Crude aniline is commercially termed aniline for red (p. 544), the significance of which is plain as these dyes obtained from it are of a general red color. 

The addition of CofKbpy) to dioxygen-saturated acetonitrile solutions of N-methyl anilines catalyzes their demethylization via a mono-oxygenase pathway to give formaldehyde and demethylated aniline.15 This is analogous to the chemistry facilitated by cytochrome P-450 proteins with N-methyl anilines. The Coll(bpy) /02/MeCN system also dehydrogenates benzylamines and basic benzyl alcohol. 

The A G values are the easiest to interpret. Amongst these mono-methyl derivatives, the iiitroductiou of a methyl group into any position of pyridine, aniline or benzoic acid causes, in general, an increase in AO (The exceptions to this generalization are (i) o-toluidine and (ii) o-toiuic acid.) This effect is usually attributed, in a somewhat sweeping way, to the inductive effect of the methyl group, which decreases the ease with which the proton is lost by the acid. 

In all cases, the mono-N-methylated anilines (ArNHCH3) are obtained with a high selectivity (92-97%) at conversions ranging from 72 to 93%. However, deactivated substrates have much longer reaction times than does aniline. 

Under the same conditions, DMC also reacts with primary aromatic amines and phenols to selectively give mono-N-methylated anilines and anisoles, respectively (17,18). 

In the presence of these solid catalysts, different anilines—even deactivated by both electronic and steric effects—yield the corresponding mono-A-methyl derivatives [ArNHMe] with selectivities of 93-98%, at conversions up to 95% (Scheme 4.8). ... 

As far as the mechanism of DMC-mediated mono-A-methylation reactions is concerned, adsorption phenomena of reagents over zeolite catalysts have to be examined. Model cases of aniline and DMC are suitable to this investigation. 

Based on Figure 4.6 and Scheme 4.12, the proposed mechanism for the mono-A-methyl of aniline with DMC is described pictorially on Scheme 4.13. Once the reagents (amine and DMC) diffuse into the supercages of NaY, they can approach each other only according to the steric requisites of their adsorption... 

Mono- and di-A-methylation of aniline are important reactions for the synthesis of intermediates in fine chemicals manufacture. Aniline methylation by methanol... 

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