1670-17-3

The title compound, C8H9N3O4, has both the o-nitro group and the 1-dimethylamino group twisted out of the plane of the benzene ring, whereas the p-nitro group is almost coplanar with the ring.

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A reaction of aromatic halides bearing electron-withdrawing groups with tertiary amines in the presence of an iridium catalyst under blue light irradiation is described. Products of the aromatic substitution of the halide by the dialkylamino fragment are

A practical and convenient procedure for the nucleophilic aromatic substitution of aryl fluorides and chlorides with dimethylamine was developed using a hydroxide-assisted thermal decomposition of N,N-dimethylforamide. These conditions are tolerant of nitro, nitrile, aldehyde, ketone, and amide groups but will undergo acyl substitution to form amides for methyl esters and acyl chlorides. Isolated yields of the products range from 44% to 98%, with the majority being greater than 70% for 17 examples.

A heterogeneous CoII/Al2O3 catalyst efficiently catalyses the N-arylation of N-heterocycles and open-chain secondary amines by activated chloroarenes and chloroheteroarenes under ligand-free conditions in water to give a series of functionalized tertiary amines. The catalyst was prepared by immobilizing CoBr2 onto the surface of Al2O3, and was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and energy-dispersive X-ray analysis. This catalyst could be recycled up to six times without any appreciable loss of catalytic activity. A heterogeneous CoII/Al2O3 catalyst efficiently catalyses the N-arylation of N-heterocycles and open- or closed-chain secondary amines by activated chloroarenes and chloroheteroarenes under ligand-free conditions in water to give a series of functionalized tertiary amines.

Taking advantage of Pd(OAc)2-catalyzed dinitration reactions with Bi(NO3)3·5H2O in trifluoroethanol (TFE) and trifluoroacetic acid (TFA), we have developed an efficient and practical method for the synthesis of secondary dinitro-aromatic amines. The products could be applied to the preparation of 5-amine-N-methyl-benzimidazolone, the azo-dyes, economic advantages. The method has also been expanded to the dinitration reaction of some tertiary aromatic amines.

A simple synthetic procedure for direct formamidation and amination of aryl halides mediated by copper(II) salts was developed in open air, without an external ligand in formamide with potassium carbonate as a base. This approach is particularly efficient when electron active aryl halides are used as substrates. In these cases almost quantitative formamidation was observed.

Several N,N-disubstituted aromatic amines (3a-g) was obtained in very good yield by the reaction of adequate doubly activated aromatic or heteroaromatic halides (1a-e) with N,N-disubstituted formamides (2a-c). Analogously, starting from 4-chloro-3-pyridin

A convenient dimethylamino amination of various heterocyclic and aromatic compounds having activated chloro group has been carried out in good yields using dimethyl formamide (DMF).

The invention relates to oxidation colorants which are particularly suitable for coloring keratin fiber and to a method of coloring such fiber. The colorants contain as the preliminary oxidation dye at least one diamino aniline of the general formula (I), in which R1 to R6 independently of each other are hydrogen, a (C1-C4)-alkyl group, a hydroxy-(C2-C3)-alkyl group, a (C1-C4)-alkoxy-(C2-C3)-alkyl group, an amino-(C2-C3)-alkyl group in which the amino group can also have one or two (C1-C4)-alkyl radicals, or a 2,3-dihydroxypropyl group provided that not all substituents R1 to R6 are simultaneously hydrogen, and R1 and R2 and/or R3 and R4 and/or R5 and R6 along with the nitrogen atom to which they are attached are also an aziridine ring, an azetidine ring, a pyrrolidine ring, a piperidine ring, an azepane ring, an azocine ring or a morpholino group, thiomorpholino group or piperazino group which has another substituent R7 on the nitrogen atom which is selected from hydrogen, a (C1-C4)-alkyl group, a hydroxy-(C2-C3)-alkyl group, a (C1-C4)-alkoxy-(C2-C3)-alkyl group, an amino-(C2-C3)-alkyl group, or a 2,3-dihydroxypropyl group, and the three remaining hydrogen atoms on the benzol ring can also be replaced independently of each other by a halogen atom or a (C1-C4)-alkyl group, or the physiologically tolerable salts thereof with inorganic and organic acids. Shades of color are obtained which have a high level of brilliancy and color fastness.

Twenty-two 2,4-dinitroanilines were synthesised and their pK(a) values were determined. The 2,4-dinitroanilines and their protonated forms were studied by 15N NMR spectroscopy. The relations between the 15N NMR chemical shifts and the pK(a) values of the 2,4-dinitroanilines and their salts were found to be linear. The deprotonation reaction of N-methyl-2,4- dinitroanilines and N-methyl-2,4,6-trinitroaniline by MTBD was successful only for the latter and yielded protonated MTBD molecule and the anion in which the electrons are strongly delocalised. The kinetic parameters of the 2,4-dinitroanilines in reactions with hydroxide ions in mixed solvent DMSO:water (95:5, v/v) were determinated and discussed. (C) 2000 Elsevier Science B.V.

Orientation of the VNS reaction in nitroaniline derivatives is mostly governed by the conjugation between the nitro groups and the amino group, which could be also deprotonated under the reaction conditions.

The following macrocylic compounds: 1-N-12C4-2,4-dinitrobenzene, 1-N-15C5-2,4-dinitrobenzene and 1-N-18C6-2,4-dinitrobenzene were synthesized. Kinetics and spectroscopic studies of reactions between these compounds and alkali metal hydroxides (LiOH, NaOH, KOH, RbOH and CsOH) in mixed solvent DMSO water (95:5 v/v) were investigated. The results were compared to analogous reactions of 1-X-2,4-dinitrobenzenes. These studies show that the kinetics of the formation of both 3-hydroxy complex and phenolate ions depend strongly on the size of the cation. The formation of the stable complex of cations and 1-N-crown ether-2,4-dinitrobenzene increases the rate constant of formation of both 3-hydroxy complex and phenolate ions. The process of complex formation between the alkali metal cation and macrocylic compounds in mixed solvent DMSO : water is very fast and precedes the nucleophilic attack of hydroxide ion on the benzene ring.

Aromatic amines can be obtained from 2,4-dinitrobenzenesulfonic acid sodium-salt and aliphatic amides in excess at 170-180 deg C, for 6-7 hours.The steric hindrances have an important role in this reaction.

The possibility of the arylation of 5-amino-3-methylthio-1H-1,2,4-triazole (1) with different chlorobenzenes activated by a nitro group was studied.The ratio of products obtained was determined by hplc using isolated products as standards.It was stated that from among the monoarylated products 8, 9 and 10 obtained the main product is 8.However, from the reaction mixtures diarylated derivatives 11 and 12 and different by products such as 15, 16, 22, 24, 25, 27, 28, 32, 36, and 38 were also isolated.

Different activated N-arylpyrazoles, as N-(2',4'-dinitrophenyl)-3,5-dimethylpyrazole, N-picryl-3,5-dimethylpyrazole etc., can react with excess formamides, as formamide N-methylformamide and N,N-dimethylformamide, at 165-175 deg C, for 5-6 hours, resulting amines in high yieds.This reaction is influenced by steric hindrance.

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Aminolysis of four oxime ethers (o-aryl ethers) having structural variation in oxime moiety with two secondary amines, viz. dimethylamine and piperidine in 1:1 water-acetonitrile has been reported.Reactions proceed to give the expected aminolysis product without accumulation of any substantial concentration of stable intermediate during the reaction.Secondary amine seems to promote base catalysis, which is explained on the basis of intramolecular H-bonding between the ammonium proton of the zwitterionic intermediate and the ortho-nitro group.Thermodynamic parameters for uncatalysed and catalysed route have been calculated for the reaction of two oxime ethers.

In the reactions of 1-dlalkylamino-2,4,6-trinitro- and 1-dialkylamlno-2, 4-dinitrobenzenes with various amines in dimethyl sulfoxide, 1-dialkylamino group is easily replaced with primary n-alkylamines at room temperature, and in a low yield with pyrrolidine only among secondary amines.

The protonation equilibria of several tertiary anilines were studied in concentrated sulfuric acid.It was found that these equilibria were adequately described by H0, the Hammet acidity function, if water was included as a reactant and its changing activity taken into account in formulating the equilibrium expressions. - Keywords: Protonation equilibria / Tertiary anilines / Hydration

The reaction of 2,4-disubstituted chlorobenzenes with 3-dialkylaminopropionitriles at 65-170 deg C leads to the formation of 2,4-disubstituted N,N-dialkylanilines, and the reaction with 3-alkylaminopropionitriles at 20-130 deg C leads to the formation of 2,4-disubstituted N-alkyl-N-β-cyanoethylanilines.In addition, in the latter case at high temperature (130 deg C) the cyanoethyl group is removed from the substituted N-alkyl-N-β-cyanoethylaniline with the formation of the 2,4-disubstituted N-alkylaniline.

The effect of benzoyl and hydrogen peroxides in the reaction of 2,4-dinitrochlorbenzene with triethylamine in DMFA was studied.The increase in the formation rate of the reaction products (2,4-dinitrophenol and N,N-diethyl-2,4-dinitroaniline) is due to the reaction of the 2,4-dinitrochlorobenzene with the products from the reaction of triethylamine with the peroxides, i.e., diethylamine and benzoic acid in the case of benzoyl peroxide and triethylamine-N-oxide in the case of hydrogen peroxide.The oxidative nucleophilic substitution reaction of 2,4-dinitrochlorbenzene with triethylamine takes place in parallel.

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