Dimethyl anilines, oxidation

The central carbon atom is derived from an aromatic aldehyde or a substance capable of generating an aldehyde during the course of the condensation. Malachite green is prepared by heating benzaldehyde under reflux with a slight excess of dimethyl aniline in aqueous acid (Fig. 2). The reaction mass is made alkaline and the excess dimethylaniline is removed by steam distillation. The resulting leuco base is oxidized with freshly prepared lead dioxide to the carbinol base, and the lead is removed by precipitation as the sulfate. Subsequent treatment of the carbinol base with acid produces the dye, which can be isolated as the chloride, the oxalate [2437-29-8] or the zinc chloride double salt [79118-82-4]. 

Methyl violet [8004-87-3] Cl Basic Violet 1 (17), is made by the air oxidation of dimethyl aniline in the presence of salt, phenol, and a copper sulfate catalyst. Initially, some of the dimethyl aniline is oxidized to formaldehyde and /V-methyl aniline under those conditions. The formaldehyde then reacts with dimethyl aniline to produce N,N,]S7,1S7-tetramethyldiaminodiphenylmethane, which is oxidized to Michler s hydrol [119-58-4]. The hydrol condenses with... 

Oxidative Couplings of Heterocyclic Hydrazones. This method has opened the way to the preparation of azo derivatives of diazo compounds unobtainable by other means, ie, heterocycHc compounds ia which the diazotizable amino group is conjugated with the heterocycHc nitrogen atom as ia 2- and 4-amiQopyridine, compounds which do not normally yield stable diazonium salts (38). The reaction occurs as illustrated by equation 7 for the iateraction of (A/-methylcarbostyryl)hydrazone [28219-37-6] and dimethyl aniline the overall process is oxidation. 

Pyridin-, Chinolin- und N,N-Dimethyl-anilin-N-oxid werden elektrolytisch an Queck-silber in Methanol/Tetramethylammoniumchlorid zu Pyridin (81% d.Th.), Chinolin (78% d.Th.) bzw. N,N-Dimethyl-anilin (78% d.Th.) (galvanostat. bei 5 A/65°C) redu-ziert1. Analog verhalten sich 2- und 4-Methyl-pyridin-N-oxide (2-Methyl-pyridin 96% 4-Meihyl-pyridin 80% d.Th.)1. 

The polymer resulting from oxidation of 3,5-dimethyl aniline with palladium was also studied by transmission electron microscopy (Mallick et al. 2005). As it turned out, the polymer was formed in nanofibers. During oxidative polymerization, palladium ions were reduced and formed palladium metal. The generated metal was uniformly dispersed between the polymer nanofibers as nanoparticles of 2 mm size. So, Mallick et al. (2005) achieved a polymer- metal intimate composite material. This work should be juxtaposed to an observation by Newman and Blanchard (2006) that reaction between 4-aminophenol and hydrogen tetrachloroaurate leads to polyaniline (bearing hydroxyl groups) and metallic gold as nanoparticles. Such metal nanoparticles can well be of importance in the field of sensors, catalysis, and electronics with improved performance. 

Anodic oxidation of phenylamines is irreversible and involves the loss of two electrons and a proton to give a delocalised carbonium ion, which reacts further. Oxidation of 2,4-dimethyl-aniline to give 51 illustrates the process [161]. Interae-... 

A number of related couplings have been reported during the synthesis of the alkaloid ( )-cryptopleurine149 and also intramolecular coupling of diaryl amides to dibenzazepine and dibenzazodne structures.150 A versatile method for the preparation of tetrahydroquinolines and jololidines has been developed.151 The method involves the anodic oxidation of AT,AT-dimethyl-aniline in methanol to afford a-methoxylated or a, a -dimethoxylated compounds and subsequent treatment of products with Lewis acids in the presence of olefins. 

Crystal violet (20) can be produced directly from formaldehyde and dimethyl-aniline. The methane base (18), WAfW,W-tetramethyl-4,4 -mcthylcncdianilinc, is formed initially. This is then oxidized to Michler s hydrol (12), which condenses with another molecule of dimethylaniline to give leuco crystal violet (19). The latter is converted to the dye in a second oxidation step. Pararosaniline, methyl violet, and Victoria blue can also be obtained by this reaction sequence. 

Attack other than on the amino group apparently does represent a competitive reaction course when the substituents on the aromatic ring are less electronegative than the nitro group. This is demonstrated by the strong coloration and tar formation observed when N,IV-dimethyl-aniline and p-chloro-N,A7-dimethylaniline are ozonized and by the fact that more ozone is consumed by these compounds than can be accounted for by side chain oxidation (Table III, Experiments 1 and 2). 

Triphenylbismuth carbonate (2) displays remarkable chemoselecdvity, aUowing alcohol oxidation in the presence of benzenethiol, pyrrolidine, indole, aniline, dimethyl aniline and 3-pyrolidinocholesta-3,S-diene. The diol moiety in (3) is cleaved selectively without oxidizing the dithioacetal function (equation 3). The rate of the stoichiometric oxidative cleavage of ciJ-cyclohexane-l,2-diol to adipic aldehyde with Ph3BiC03 is faster than that of the trans isomer, suggesting the formation of a cyclic organobismuth intermediate (4 Scheme 1). ... 

Ogata and Tabushi studied the kinetics of oxidation of some N,N-dimethyl-anilines in aqueous solutions of pH 1-12 at 25 °C (some runs were performed at other temperatures in the range 15-30 °C). The product of oxidation is an amine oxide, viz. 

C13H14N40 pyridine-1-oxide-3-azo-p-dimethyl aniline 59405-47-9 553.65 49.062 2 26167 C13H18CINO solan 2307-68-8 483.15 42.268 2... 

Oxidation of tertiary amines with N-chloronylon 6,6 has also been investigated in several solvents Thus, N-chloronylon has been found to oxidize N J -dimethyl-aniline at room temperature to N-methylaniline in 15—50% yield, depending on the solvent used. The oxidation of NJM-dimethylbenzylamine gives benzddehyde in 15-30% yield and a small amount of N-methylbenzylamine. A comparison of these oxidations with those using the low molecular wei t analoges, e. g. N-chlorosuccin-imide, indicates that in both cases the reaction paths are similar. However, the poor yields observed in these oxidations of amines make these polymeric oxidizing agents unsuitable for amine oxidations. 

Furfural can be and has been used as a fuel for motor cars and airplanes. Under the trade name of FURALINE, a mixture of furfuryl alcohol, methanol, and xylidine (dimethyl aniline) is used as a rocket fuel. With nitric acid as oxidizer, a mixture of furfuryl alcohol with aniline is used as the fuel for the American CORPORAL rockets and the French VERONIQUE and EMERAUDE rockets. The latter system is hypergolic When the mixture of furfuryl alcohol and aniline (the fuel ) comes into contact with the nitric acid (the oxidizer ), it ignites by itself without external aid. Even alone, furfuryl alcohol explodes when mixed with concentrated nitric acid. 

Azyline), is formed by the action of nitric oxide on dimethyl-aniline, and by action of paradiazodimethylaniline on the same amine [22]. 

Tetramethyldiamidotriphenylcarbinol, or more correctly its anhydride, is formed by oxidation of tetramethyldiamidotriphenyl-methane [3], and by condensation of two molecules dimethyl-aniline with one molecule benzotrichloride in presence of zinc chloride [4]. It may also be obtained from benzoyl chloride and dimethylaniline [3] by action of the air. 

This compound is obtained by oxidation of dimethylparaphenylenediamine in presence of sodium hyposulphite, or by action of hyposulphurous acid (thiosulphuric acid, H2S2O3) on the red oxidation product of dimethylparaphenylenediamine. Two processes may be employed for the manufactnre of methylene blue from this compound. (1) The thiosulphonic acid is oxidised with dimethyl-aniline, whereby an insoluble compound ... 

In some methods, the final mixture is acidified slightly to stop the reaction, and the intensity of the yellow chro-mophore is measured at 400 nm. In stronger acid solution, the color becomes pink, with maximum absorbance at 540 nm, and both sensitivity and stability are improved. Other approaches to measurement of the H2O2 produced include the peroxide-mediated oxidative coupMng of 3-methyl 2-benzothia2olinone hydrazone (MBTH) with N,N-dimethyl-aniline (DMA) catalyzed by peroxidase or the oxidative coupHng of p-aminophenazone (PAP) to phenoi. Both procedures have been automated. The... 

The union, effected by the oxidation between the pentavalent nitrogen atom of the dimethyl aniline residue and the common methane-carbon atom, was considered to be the condition which determined the nature of the dve- At present, the view that the latter is determined by the presence of the quinofie-like secondary benzene residue is generally accepted, and the formula of the dye-salt is written thus ... 

Indeed, it may be considered as a hexamethyl parafuchsine. It is prepared technically in the same way, and forms the principal constituent of the Methyl Violet obtained by the oxidation of dimethyl aniline. 

Aromatic amines have such low oxidation potentials that they are ordinarily oxidized when treated with a cation radical. The amine cation radical is then most likely to dimerize. The dimerization reaction may itself be looked upon as either the reaction of the amine cation radical with another molecule of amine or the dimerization of two cation radicals, as is illustrated with N,N-dimethyl-aniline in (145) and (146). The electrochemical literature is replete... 

CHEMICAL PROPERTIES derived by the action of benzenediazonium chloride on dimethyl aniline will not polymerize incompatible with strong acids and strong oxidizing agents. 

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