Aniline A-methyl

Secondary steric effects of the same kind have been found in the reaction of methyl derivatives of 22 with aniline. A methyl group at position 6 has a 4-fold rate-diminishing effect (mainly inductive), but when positions 4 and 6 are both methylated the effect is 81-fold and is mainly of steric origin. 

A summary of aniline N-methylation mechanistic features on Cui xZnxFe204 ferrospinel catalysts is given in Figure 27. It was possible, due to in-situ IR studies, to observe a dissociative adsorption and possible orientation of reactants on the catalyst surface, their conversion to product at low temperatures, and desorption-limited kinetics, all under conditions that are close to the reaction conditions. Although Cu is the active center for the aniline A-methylation reaction, and IR studies reveal that Zn acts as the main methyl species source. 

Methylene-1-oxo-1,2,3,4-tetrahydro-naphthalene l(2//)-Naph-thalenone, 3,4-dihydro-2-methylene- (8,9) (13203-73-1) N-Methylanilinium trifluoroacetate Aniline, A-methyl-, trifluo-roacetate (8) Benzenamine, /V-methyl-, trifluoroacetate (9) (29885-95-8)... 

Aniline, 2-chloro- [Benzenamine, 2-chloro-j, p-bromination of, 55, 23 Aniline, 3-chloro- [Benzenamine, 3-chloro-[, p-biomination of, 55, 23 Aniline, A, Al-diethyl- [Benzenamine, JV,7V-diethyl-], p-bromination of, 55, 23 Aniline, (V,iV-diraethyl- [Benzenamine, N,N-dimethyl-], p-bromination of, 55, 23 Aniline, 2,3-dimethyl- [Benzenamine, 2,3-dimethyl-], p-bromination of, 55, 23 Aniline, 2,5-dimethyl- [Benzenamine, 2,5-dimethyl-], p-bromination of, 55, 23 Aniline, 3,5-dimethyI- [Benzenamine, 3,5-dimethyl-], p-bromination of, 55, 23 Aniline, A fV-dimethyl-3,-(trifluoiomethyl)-[Benzenamine, JV,7V-dimethyl-3-tri-fluoromethyl-], 55,21 Aniline, 3-methoxy- [Benzenamine, 3-meth-oxy-], p-bromination of, 55, 23 Aniline, A -methyl- [Benzenamine, iV-meth-yl-], p-bromination of, 55, 23 Aniline, 2-methyl-A, Af-dimethyl- [Benzenamine, 2,Al,fV-ltimethyl-), p-bromination of, 55, 23... 

OtherNames Aniline,A -methyl-M2,4,6-tetranitro- 2,4,6,A-Tetranitro-A-methylaniline 2,4,6-Tetryl 2,4,6-Trinitro-N-methyl-A-nitroaniline 2,4,6-Trinitrophenyl-A-methylnitramine 2,4,6-Trinitro-phenylmethylnitroamine CE A-Methyl-A,2,4,6-tetranitroaniline A-Methyl-A-picrylnitramine A-Picryl-A-methylnitramine NSC 2166 Nitramine Nitramine (indicator) Picrylmethylnitra-mine Picrylnitromethylamine Tetralit Tetralite Tetril Tetryl CA Index Name Benzenamine, A-methyl-A,2,4,6-tetranitro-CAS Registry Number 479-45-8 Merck Index Number 6573 Chemical Structure... 

Ohsaka et al. [131] studied the pol)mierization of N-ALdialkyl substituted anilines such as iV,A -dimethyI aniline, A, 7V-diethyl aniline, A -methyl ALethyl aniline and A/ A -dibutyl aniline. The authors have reported that these polymers do not have well-defined voltammetric peaks. They also described the ion exchange property of these polymers by incorporating Fe(CN)6 , Ru(bpy)3 +, Ru(NH3)6, Mo(CN)6 ", IrCle ", Os(CN)6 , Ru(CN)6 and Fe (Phen)3 +. ... 

With cold aniline, (a) Methyl carbanilate. (h) Ethyl carbanilate. (c) The anilic acid. 

Secondary and tertiary amines are not generally prepared in the laboratory. On the technical scale methylaniline is prepared by heating a mixture of aniline hydrochloride (55 parts) and methyl alcohol (16 parts) at 120° in an autoclave. For dimethylaniline, aniline and methyl alcohol are mixed in the proportion of 80 78, 8 parts of concentrated sulphuric acid are added and the mixture heated in an autoclave at 230-235° and a pressure of 25-30 atmospheres. Ethyl- and diethyl-anihne are prepared similarly. One method of isolating pure methyl- or ethyl-aniline from the commercial product consists in converting it into the Y-nitroso derivative with nitrous acid, followed by reduction of the nitroso compound with tin and hydrochloric acid ... 

Thus good yields (> 60 per cent) are obtained with aniline and methyl, ethyl, n-propyl and n-butyl phosphates with a- and P-naphthylamine and methyl or ethyl phosphate nuclear substituted anilines and methyl or ethyl phosphate. 

The operation of the nitronium ion in these media was later proved conclusively. "- The rates of nitration of 2-phenylethanesulphonate anion ([Aromatic] < c. 0-5 mol l i), toluene-(U-sulphonate anion, p-nitrophenol, A(-methyl-2,4-dinitroaniline and A(-methyl-iV,2,4-trinitro-aniline in aqueous solutions of nitric acid depend on the first power of the concentration of the aromatic. The dependence on acidity of the rate of 0-exchange between nitric acid and water was measured, " and formal first-order rate constants for oxygen exchange were defined by dividing the rates of exchange by the concentration of water. Comparison of these constants with the corresponding results for the reactions of the aromatic compounds yielded the scale of relative reactivities sho-wn in table 2.1. 

Hydroperoxide Process. The hydroperoxide process to propylene oxide involves the basic steps of oxidation of an organic to its hydroperoxide, epoxidation of propylene with the hydroperoxide, purification of the propylene oxide, and conversion of the coproduct alcohol to a useful product for sale. Incorporated into the process are various purification, concentration, and recycle methods to maximize product yields and minimize operating expenses. Commercially, two processes are used. The coproducts are / fZ-butanol, which is converted to methyl tert-huty ether [1634-04-4] (MTBE), and 1-phenyl ethanol, converted to styrene [100-42-5]. The coproducts are produced in a weight ratio of 3—4 1 / fZ-butanol/propylene oxide and 2.4 1 styrene/propylene oxide, respectively. These processes use isobutane (see Hydrocarbons) and ethylbenzene (qv), respectively, to produce the hydroperoxide. Other processes have been proposed based on cyclohexane where aniline is the final coproduct, or on cumene (qv) where a-methyl styrene is the final coproduct. 

It was reported only recently that A-methyl transfer from an oxaziridine to an amine occurs with formation of an N—N bond (79JA6671). N—N bond forming reactions with A-unsubstituted oxaziridines had been found immediately after discovery of this class of compound (64CB2521) and have led to simple hydrazine syntheses (79AHC(24)63). Secondary amines like diethylamine or morpholine are A-aminated by (52) in the course of some minutes at room temperature with yields exceeding 90% (77JPR195). Further examples are the amination of aniline to phenylhydrazine, and of the Schiff base (96) to the diaziridine (97). 

Diffusion-limited rate control at high basicity may set in. This is more eommonly seen in a true Br nsted plot. If the rate-determining step is a proton transfer, and if this is diffusion controlled, then variation in base strength will not affect the rate of reaction. Thus, 3 may be zero at high basicity, whereas at low basicity a dependence on pK may be seen. ° Yang and Jencks ° show an example in the nucleophilic attack of aniline on methyl formate catalyzed by oxygen bases. 

During the 1950s and 1960s Hafner used Konig salts, derived from the reaction of A -methyl aniline with Zincke salt 1, for azulene synthesis. The Zincke reaction also achieved prominence in cyanine dye synthesis and as an analytical method for nicotinamide determination. ... 

The reaction conditions of this modified indazole synthesis can also be applied to the preparation of 1,2-diazanaphthalenes, the so-called cinnolines, although in such syntheses no deprotonation prior to cyclization is likely to occur. Ruchardt and Hassmann (1980) obtained 4-phenylcinnoline (6.85) in 53% yield from 2-(a-methyl-ene-benzyl)aniline (Scheme 6-53). 

Aniline, 3-methyl-A,A -dimethyl [Benzen-amine, 3rV,A -tnmethyl-, p-bromina-tion of, 55, 23... 

Benzenamine, 3,5-dimethyl- [Aniline, 3,5-dimethyl ], p-biomination of, 55, 23 Benzenamine, 2,/V-dimethyl- [Aniline 2-methyl-A-methyl-]. p-biomination of, 55, 23... 

Initially, a reaction of A-acetoxy-A-butoxybenzamide 25c with A-methyl aniline 61 in butyl benzoate 63(R = Bu) and acetic acid. Close examination of these highly coloured reaction mixtures indicated the presence of crystals of A,A-dimethyl-A,A-diphenyltetrazene 65 (Scheme 11, R = Bu). The reaction is promoted by polar solvents as reactants are unchanged in pure acetonitrile. A crossover experiment using a mixture of /V- a ce t o x y - A-- b u t o x y - to 1 u a m i d e 26d and A-acetoxy-A-ethoxybenz-amide 25a afforded clean yields of butyl /Moluatc and ethyl benzoate thus pointing to an intramolecular rearrangement.41... 

In reactivity, the same series of mutagens exhibited positive Hammett correlations for AaiI acid catalysed solvolysis (p — + 0.32) and SN2 reactivity with A-methyl-aniline (p — + 1.7), hydroxide (p — +0.55) and L-cysteine ethyl ester (p — + 1.1), all reactions in which the benzoyloxyl group leaves with electrons and which are therefore accelerated by electron-withdrawing groups. The negative Hammet p-value for... 

The technical preparation of crystal violet and of its methyl-free parent substance, parafuchsine, almost the oldest of the triphenylmethane dyes, is not so easily explained. As is well known, in this process aniline and p-toluidine are united by oxidation in an acid melt. (In the preparation of fuchsine itself, which contains a methyl group attached to one of the benzene rings, o-toluidine is an additional ingredient.) Although all the phases of this important synthesis have not yet been experimentally established, we may nevertheless explain it on the basis of a dehydrogenation similar to that involved in the formation of malachite green. Moreover, the union of several molecules of base proceeds exactly according to the principle on which indamines are formed (p. 321) (Bucherer). 

Menshutkin reaction between jV,Ar-dimethyl-d6-aniline and methyl tosylate in nitrobenzene at 51.3°C (21) is consistent with an inductive KIE resulting from the increased electron density on the nitrogen (the nucleophilicity), a steric explanation was preferred for three reasons. 

Ridd and coworkers71 have now shown unequivocally that radical pairs are indeed involved in this rearrangement by observation of strong enhancement of 15N NMR signals in both the reactant and product, when reaction was carried out with 15N-labelled nitro groups in both A-methyl-A-nitroaniline and also in A-methyl-A-nitro-2,5-dichloro (and dibromo) aniline. 

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... 

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