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Hydrogen-bonded aggregates of B(C 6 F 5 ) 3 and water are proven as strong Brønsted acid catalysts, which have the advantages of low toxicity and broad compatibility. Sulfoxonium ylides are stable surrogates of diazo compounds, which participate in various reactions due to their versatile reactivity. Based on these characteristics, a strategy for C-N bond or C-C bond construction of aromatic amines with sulfoxonium ylides under metal-free catalytic conditions was established. This method has advantages of mild conditions and excellent yield, which is suitable for the N-H or C-H functionalization of various aromatic amine compounds.

Polymer-supported triorganotin halides are used in the halogenation reaction of aromatic amines. Treatment of aromatic amines with n-butyllithium and polymer-supported organotin halides gives the corresponding polymer-bound N-triorganostannylamines, which by treatment with bromine or iodine monochloride gives the para-halogenated aromatic amines with high yields and high selectivities.

Nuclear amination of p-hydroquinones with primary aromatic amines was catalyzed by fungal laccases (EC 1.10.3.2) from Trametes spec. and Myceliophthora thermophila. Incubation of the two products with laccase in the presence of oxygen resulted in the formation of corresponding monoaminated or diaminated quinones.

Research has been conducted on the trifluoromethyl epoxy ethers. The reaction of these ethers with aromatic amines in hexafluoro-2-propanol at room temperature has been investigated and the results indicate that this reaction has produced trifluoromethyl indolinols.

A visible-light-induced cascade cyanoalkylsulfonylation/cyclization/aromatization of N -propargyl aromatic amines with K 2 S 2 O 5 and cyclobutanone oxime esters for the construction of cyanoalkylsulfonylated quinolines is developed. This cascade transformation features mild reaction conditions, a broad substrate scope, and excellent functional group compatibility, providing a convenient route toward cyanoalkylsulfonylated quinolines via the formation of a C-C bond and two C-S bonds in one step.

Research demonstrates that enamines are converted to arylamines, in a one-pot reaction, with the addition of stoichiometric amount of palladium salts in acetonitrile in the presence of triethylamine. Application of this strategy to convert acyclic enone to aromatic amine is discussed.

A new type of well-defined neutral mono- and dicationic ruthenium(II) complexes with a neutral terdentate donor system (C5H3N(CH2E)2-2,6) (E = PPh2 or NMe2 (NN'N)) was observed to be an effective catalyst precursor in N-(cyclo)alkylation reactions of aromatic amines with diols Y(CH2CH2OH)2 (Y = CH2, NR). Using the above catalysts, N-phenylpiperidine was synthesized from aniline and 1,5-pentanediol with 85% yield.

Despite a large number of synthesis procedures for pyrazoles known today, those directly employing primary amines as substrates are rare. Herein, we report an original method for the preparation of N -alkyl and N -aryl pyrazoles from primary aliphatic or aromatic amines as a limiting reagent of the reaction. The protocol utilizes no inorganic reagents and requires a short reaction time, mild conditions, and the use of structurally simple and commercially available starting reagents. During this study, pyrazoles containing a wide variety of N -substituents were obtained using the same procedure for both aliphatic and aromatic amines.

The rate of reaction between the carbon-centered radicals and diarylamines were investigated. Specifically, the hydrogen atom abstraction from diarylamine of the type (4-X-C6H4)2NH where X = H,CH3,C8H17,CH3O,Br by the 2-methyl-2-phenylpropyl radical was examined through the thermolysis of 3-methyl-3-phenylbutanoyl peroxide in the presence of different amines in dodecane solution. Hydrogen abstraction experiments on 4,4'-disubstituted diphenylamines using bromine, methyl, methoxyl, tert- and tert-octyl (2-neopentylpropane) substituents were also performed.

Various aromatic amines were oxidized selectively to their corresponding nitroso or nitro compounds and cooxidized in the presence of aliphatic amines using aqueous hydrogen peroxide and heteropolyoxometalates as catalysts. Peroxotungstophosphate-catalyzed oxidation of anilines with 35% H2O2 following two-phase conditions and with chlroform as solvent facilitates the formation of substituted nitroso compounds. When performed at reflux temperature, the process allows highly selective aniline conversion into nitro compounds. Aniline- and aliphatic primary amine-cooxidation offers a direct method for preparing phenylazoxyalkanes.

A unimolecular nucleophilic substitution (SN1) mechanism characterizes the reaction of N-(sulfonatooxy)-2-(acetylamino)fluorene with the aromatic amines, aniline and N,N-dimythelaniline. The observations on the kinetics and products of the reaction reveal the occurrence of an insubstantial overall rate effect and independent product yields. The study shows that the steric hindrance caused by the nitrogen in the fluorene compound apparently facilitates the alteration of the SN2 process leading to the development of the SN1 process.

The reaction of N,N-dimethyl-aniline N-oxide with sulfur trioxide results in the production of N,N-diemthylaniline o-hydrogen sulfate in 45% yield. This process supports the early mechanistic strategy which indicates that the resulting o-hydrogen sulfate compound is the probable intermediate in Boyland-Sims oxidation. Moreover, the ratio of p-sulfate and o-sulfate in the resulting product resembles that of the ratio produced in the persulfate oxidation of N,N-dimethylaniline. In addition, the reaction's ortho-para ratio does not exhibit any dependence on the amine-persulfate ratio, ph and amine concentration factors.

A metal-free borylation process based on Sandmeyer-type transformation using arylamines derivatives as the substrates has been developed. Through optimization of the reaction conditions, this novel conversion can be successfully applied to a wide range of aromatic amines, affording borylation products in moderate to good yields. Various functionalized arylboronates, which are difficult to access by other methods, can be easily obtained with this metal-free transformation. Moreover, this transformation can be followed by Suzuki--Miyaura cross-coupling without purification of the borylation products, which enhances the practical usefulness of this method. A possible reaction mechanism involving radical species has been proposed. [ABSTRACT FROM AUTHOR]

The allylation of aromatic amines with alkynes proceeded smoothly in the presence of catalytic amounts of Pd(PPh3)4 and benzoic acid. The allylation products were obtained in high yields in a regio- and stereoselective manner. The effect of various groups on the nitrogen atom of anilines was studied. Regardless of the substituent (electron withdrawing or electron donating) on the aromatic ring, the reaction proceeded well. Various functionalities, including -CH3, -OMe, -Cl, -CN, -COOMe, -NO2 and -COCH3 were tolerated under the reaction conditions. Similarly, the allylation of α-aryl aldehydes proceeded well with the same level of regio- and stereoselectivity as the allylation of aromatic amines. This reaction provides the second example of the transition metal catalyzed direct α-allylation of aldehydes. [ABSTRACT FROM AUTHOR]

Research has been conducted on the aromatic amines and cyclic ethers. The synthesis of different tetrahydroquinoline derivatives carried out via the use of the domino reaction of these aromatic amines and cyclic ethers is described.

Investigates the reaction of primary aromatic amines with alkyl carbonates over sodium yttride faujasite. Characterization of aromatic amines; Selectivity of mono-N-alkyl anilines; Effect of triglyme on mono-N-alkyl selectivity.

A nickel-catalyzed intramolecular C-N coupling reaction via SO 2 extrusion is presented. The use of a catalytic amount of BPh 3 allows the transformation to take place under much milder conditions (60 °C) than previously reported C-N coupling reactions by CO or CO 2 extrusion (160-180 °C). In addition, this method displays good functional group tolerance and versatility, as it can be applied to the synthesis of dialkyl aryl amines, alkyl diaryl amines, and triaryl amines. The robustness of the desulfitative C-N coupling is demonstrated by three high-yielding gram-scale reactions.

A novel, efficient procedure for the cleavage of epoxides with aromatic amines was described. The aim was to elucidate the unusual preference in the epoxide cleavage with aromatic amines using Cu(OTf)(sub 2). Experimental results showed that highly deactivated amines opened the epoxides in a reasonable yield and that the epoxide opening reaction tolerated a varying level of steric hindrance on aromatic amines. These results indicate that the cleavage of epoxides with aromatic amines is a unique process and presents promise in organic synthesis.

Reports on a convenient reductive deamination (hydrodeamination) of aromatic amines, an important transformation in organic chemistry. Amination of the corresponding arylamine methanesulfonamides using chloroamine under alkaline conditions; Ability of the intermediate aryl methanesulfonylhydrazines to eliminate methanesulfinic acid, affording diazenes which extrude nitrogen; High yield occurrence of both sulfonamide formation and reduction reactions.

Results show that aromatic amines and the corresponding amino alcohols can be synthesized by opening the epoxide ring using hexafluoro-2-propanol. Data indicate that the compound deactivates alkylamines facilitating ring opening in oxiranes.

1,4-Addition of anilines onto Michael acceptors proceeds easily in specific polar protic solvents, without any promoting agent. According to the solvent and to the electrophile, the selectivity of the reaction can be finely tuned. With methyl acrylate as electrophile, only monoaddition takes place in water, while the diadduct is yielded in hexafluoroisopropyl alcohol (HFIP). The use of methyl vinyl ketone as a partner affords the monoadduct in water, the diadduct in trifluoroethanol (TFE), and the quinoline in HFIP. [ABSTRACT FROM AUTHOR]

A chemo- and regioselective copper-catalyzed cross-coupling procedure for amination of 2-bromobenzoic acids is described. The method eliminates the need for acid protection and produces N-aryl and N-alkyl anthranilic acid derivatives in up to 99% yield. N-(1-Pyrene)anthranilic acid has been employed in metal ion-selective fluorosensing. Titration experiments showed that this pyrene-derived amino acid forms an equimolar complex with Hg(II) in water resulting in selective fluorescence quenching even in the presence of other metal ions such as Zn(II) and Cd(II). [ABSTRACT FROM AUTHOR]

The asymmetric Friedel-Crafts reaction of a variety of N,N-dialkylanilines with ethyl glyoxylate has been achieved by the catalysis of titanium complexes of BINOL derivatives to give corresponding ethyl esters of p-N,N-dialkylaminomandelic acids in high yields (85-99%) and good to excellent enantioselectivities (80-96.6% ee) under the optimized reaction conditions, which has added a new catalyst for this class of reactions. The reaction could also be carried out at a reduced catalyst loading (1 mol %) in gram scale, which provided a practical synthesis of enantiopure aminomandelic acid derivatives. [ABSTRACT FROM AUTHOR]

A new series of azulene-substituted aromatic amines and diamines with amphoteric redox behavior, N,N-di(6-azulenyl)-p-toluidenes and N,N,N',N'-tetra(6-azulenyl)-p-phenylenediamines are designed and synthesized. Azulene-substituted aromatic amines exhibit facile electrochemical oxidation owing to the amine substituent and also show electrochemical reduction because of the generation of an anion radical stabilized by the resonance effect between the two 6-azulenyl groups.

A new and easy way to produce 2-alkylaminoquinazolin-4-ones with fused heteroaromatic rings from easily available (hetero)aromatic amines is presented. The key step in the procedure involves ring closure of the N-protected guanidine intermediates by intramolecular Friedel-Craft's type substitution to yield 2-alkylaminoquinazolinone derivatives in three steps without chromatographic purification.

Research has been conducted on the aromatic amines. The reductive deamination of these amines has been carried out under alkaline conditions via the corresponding arylamine methanesulfonamide amination using chloramine and the results are reported.

A one-pot synthesis of tetrahydroquinolines via benzotriazole-promoted 'two-pair coupling' reactions of phenylacetaldehydes and aromatic amines is described. In addition, research demonstrates the synthesis of optically active tetrahydroquinolines via an asymmetric imino Diels-Alder reactions between N-(alpha-aminoalkyl)benzotriazoles and (R)-glyceraldehyde acetonide catalyzed by SmI(sub)2 or SmI(sub)3.

A procedure for the preparation of oxazines-hetero-Diels-Alder adducts from primary aromatic amines, hydrogen peroxide and conjugated dienes was developed. The reactions were conducted in the presence of a molybdenum-peroxo catalyst which catalyzes the oxidation of primary aromatic amines to form dienophilic nitroso compounds. Alkyl- and phenyl-substituted conjugated dienes and 4-chloroaniline were used as precursors for oxazines and the dienophile, respectively.

The asymmetric Friedel-Crafts reaction of aromatic compounds is discussed. The results show that the reactions enable preparation of optically active mandelic acid derivatives with important biological properties.

Research has been conducted on the synthesis of N-cyclopropyl-N-alkylanilines. The reaction with nitrous acid in aqueous acetic acid is described.

Polymer-supported triorganotin halides were used in the halogenation reaction of aromatic amines. Treatment of aromatic amines with n-butyllithium and polymer-supported organotin halides gave the corresponding polymer-bound N-triorganostannylamines, which by treatment with bromine or iodine monochloride gave the para-halogenated aromatic amines with high yields and high selectivities. The polymer-supported organotin halides reagents regenerated during the course of the halogenation reaction can be reused without loss of efficiency. The presence of tin residues in halogenated aromatic amine s was also investigated and evaluated at under 20 ppm after three runs. [ABSTRACT FROM AUTHOR]

A methodology for the preparation of 5-monosubstituted and 5,7-disubstituted indoles from the reaction of 4-substituted aromatic anilines was established. The 4-substituted anilines reacted with IPy2BF4 to form o-iodoanilines in nearly quantitative yield. In general, the synthesis of the substituted indoles proceeded in three reactions: ortho iodination of substituted anilines, reaction of o-iodoanilines with (trimethylsilyl)acetylene in the presence of palladium catalyst, and CuI-mediated nitrogen cyclization of the resulting arylacetylenes.

The synthesis of 2- 3- and (4-bromophenyl)- and (3,5-dimethylphenyl)-3,3- 1, 4-butanediyl triazenes with sec- or tert-butyllithiums produced (triazenylaryl)-lithiums by means of diazotization of the corresponding aniline followed by diazotization with pyrrolidine in aqueous KOH. The reaction was observed to have a wide scope since a variety of substituents were tolerated by reaction conditions. The reaction sequence was suggested for synthesis of aniline derivatives.

N-, 3- and 4-substituted 2-oxazolidinones can serve as carboxylated aziridine equivalents. In their thermal reactions with aniline salts and thiophenols, the 2-oxazolidinones produce N-aryl-1,2-ethanediamines and 2-(arylthio)ethanamines in fair to very high (27-94%) yields. Phenols give poor yields while aliphatic amines and mercaptans do not react at all. The aminoethylation liberates the carboxylate as carbon dioxide, the only byproduct. Thus, compared to other techniques, the use of 2-oxazolidinones does not generate toxic gases nor require secondary hydrolysis, as oxazolidines do.