Synthesis of hydroxybenzaldehyde derivatives containing an isoxazole heteroring

5-Phenyl(p-tolyl)isoxazole-3-carboxylic acids were synthesized starting from 3-hydroxyiminomethyl-5-phenyl(p-tolyl)isoxazoles, and their reactions with p-hydroxybenzaldehyde, vanillin, isovanillin, o-vanillin, and ethyl vanillin gave the corresponding esters. The latter were brought into condensation with aromatic amines to obtain Schiff bases which were reduced to amines.     

Synthesis of mannich bases of bioactive benzylphenols

2,4-Bis(1,1-dimethyl)-6-[(4-methoxyphenyl)methoxymethyl]phenol ( 4 ), prepared by oxidation of 2,4-bis(1,1-dimethylethyl)-6-[(4-methoxyphenyl)methyl]phenol ( 1 ) with silver oxide in methanol, reacts with secondary amines in boiling toluene to give Mannich bases ( 6 ) related to the biologically active o-benzylphenol. Mannich basis of the isomeric p-benzylphenol ( 7 ) were prepared by reaction of amines with the p-quinone methide formed by oxidation of 7 .     

Preparation of trimethylsilyl ethers of 3-azetidinols. Scope and Limitations

Preparation of the trimethylsilyl ethers of 1-alkyl-3-azetidinols from non-hindered primary amines and epichlorohydrin by conversion of the intermediate 1-(alkylamino)-3-chloro-2-propanols to their trimethylsilyl ethers by either N-(trimethylsilyl)acetamide or by 1-(trimethylsilyl)imidazole followed by ring closure in acetonitrile is described. This sequence of reactions fails for aromatic amines, but appears to be general for all primary aliphatic amines, although the condensation of hindered amines with epichlorohydrin occurs slowly. Several novel azetidinols, in which the N-alkyl substituent itself contains a second heterocyclic system, are reported. In addition, the pK_A's of several m. and p-substituted 1-benzylazetidinols correlates well with the Hammett equation.     

Ring-opening reaction of 1,3,4-oxadiazolone and 1,3,4-oxadiazolinethione: Reaction of 2-phenyl-1,3,4-oxadiazolin-5-one and 2-phenyl-1,3,4-oxadiazoline-5-thione with amines

The ring-opening abilities of amines toward 1,3,4-oxadiazolines, 2-phenyl-1,3,4-oxadiazolin-5-one ( 1a ) and 2-phenyl-1,3,4-oxadiazoline-5-thione ( 1b ), were investigated with relation to their basicities or pK_b values. Oxadiazolines 1a and 1b were easily reacted with amines such as benzylamine and aniline, but not with p-nitroaniline, to form the corresponding ring-opening adducts. The reactions of both 1a and 1b with o-phenylenediamine produced benzodiazoles with the liberation of benzoylhydrazide, whereas the reactions with o-aminobenzamide furnished quinazolines with the liberation of ammonia. o-Aminophenol and o-aminothiophenol were also reacted with 1a and 1b both of them giving 1,5-dibenzoylcarbohydrazide from 1a and 1,2-dibenzoylhydrazine from 1b. From the conditions affording the corresponding ring-opening adducts or reaction products, the ring-opening abilities of the amines toward 1a and 1b are in good correlation with the strength of their basicities or pK_b values. The ring-opening of oxadiazolines were proved to occur with anilines. Therefore, the other reactions are also supposed to proceed via the ring-opening steps.     

Chloroaromatic ether amines

A new and useful class of aromatic amines, based on multichlorinated benzenes and polyphenyls, has been developed. The amines are prepared by reacting the alkali metal salt of p-aminophenol with the chloroaromatics under nucleophilic substitution reaction conditions. Oligomeric amines can be obtained by condensing, e.g., the dialkali salt of bisphenol A and the alkali metal salt of p-aminophenol with the chloroaromatics. The products are mixtures of mono-, di-, and triamines, as a result of the complex functionalities of the chloroaromatics employed. Unique features of the amines include: (1) flame-retarding characteristics; (2) markedly reduced amine reactivity (compared with aniline); (3) thermal stability; (4) good solubility in the usual organic solvents.     

Spectrophotometric determination of aromatic amines by reaction with p-benzoquinone

A comprehensive study is made of the application of the p-benzoquinone spectrophotometric technique to the aromatic amines. The technique involves a reaction with excess p-benzoquinone; the colored products display maximum absorption at 490–510 nm (varying according to the type of the amine used) and E_{1 cm}^1% in the range of 90–380. On the basis of an IR investigation, ethyl alcohol has been selected as a suitable solvent medium for aromatic amine determination. Electron-donating groups react faster and give more intense color than do electron-withdrawing groups. Results with an average recovery of 95% and mean standard deviation of 3.4% are obtained with seven aromatic amines.     

The activation of amines of various structures in synergistic mixtures with quinones during the retardation of polymerization of methyl methacrylate

The retardation of the radical polymerization of methyl methacrylate (MMA) mixed with quinones (Q) is accompanied by activation of amines of various structures (InH). In the absence of quinones, primary amines (-naphthylamine), secondary amines (diphenylamine,N-phenyl--naphthylamine, dimethyl-bis-p-(phenylaminophenoxy)silane,N,N'-diphenyl-P-phenylenediamine, andN-phenyl-p-aminophenol), and tertiary amines (N,N,N',N'- tetramethylethylenediamine andN,N,N',N'-tetramethyl-p-phenylenediamine) exert no effect on the process. In the presence of 2,3,5,6-tetrachloroquinone orp-benzoquinone, amines inhibit polymerization (synergism). The consumption of amines is due to the abstraction of mobile H-atoms from their molecules. The retatdation by tertiary amines occurs only in the case when a mobile H atom is present at the-C atom of the amine; a mixture containingN,N,N',N'-tetraphenyl-p-phenylenediamine is ineffective. Analysis of various kinetic schemes shows that the activation of amine and its participation in the reaction with growing MMA radicals may occur either through the formation of active inhibitory species incorporated in the donor-acceptor complex, [InH · Q], or by inhibitory radicals, In^.and QH^., generated by the transfer of an H-atom from InH to Q.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 673–678, April, 1995.     

Effect of amines on the ceric ion-initiated polymerization of vinyl monomers. II. Polymerization of acrylonitrile by ceric ion in presence of various substituted amines

The effect of various substituted amines on the polymerization of acrylonitrile initiated by ceric ammonium sulfate has been studied in aqueous solution at 30°C. It was found that the secondary and tertiary amines considerably increased the rate of polymerization, whereas the primary amines seemed to have no effect at all. From the kinetic studies it was found that the overall polymerization rate R_p is independent of ceric ion concentration and can be expressed by the equation: R_p = k₁ [amine] [monomer] + k₂[monomer]², where k₁ and k₂ are constants (involving different rate constants). The accelerating effect of the amines was attributed to a redox reaction between the ceric ion and the amine involving a single electron transfer, the relative activity of the different amines being thus dependent on the relative electron-donating tendency of the substituents present in the amine. The mechanism of the polymerization is discussed on the basis of these results, and various kinetic constants are evaluated.     

Reactions of 5-aryl-4-acyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-ones with arylamines

The reaction of 5-(4-chlorophenyl)-4-benzoyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-one with aromatic amines affords the corresponding 3-arylamino derivatives, and the reactions of 5-aryl-4-acetyl-1-(4-hydroxyphenyl)-3-hydroxy-3-pyrrolin-2-ones with p-toluidine yield 5-aryl-4-(1-p-tolylamino)ethylene-1-(4-hydroxyphenyl)pyrrolidin-2,3-diones.     

Favorskii Rearrangement in the Reaction of 3-(1-Adamantyl)-1-chloro-2-propanone with Amines

The reaction of 3-(1-adamantyl)-1-chloro-2-propanone with amines [diethylamine, (1-adamantyl)methylamine, p-toluidine, and piperidine] in diethyl ether at room temperature involves the Favorskii rearrangement and yields N,N-disubstituted amides of 3-(1-adamantyl)propanoic acid.     

Interaction between primary aliphatic amines and carboxylic acid esters in aqueous micellar solutions of cationic surfactants

The effects of cetylpyridinium bromide (CPB) on the acid-base equilibria of primary aliphatic amines and on the kinetics of reactions of the amines withp-nitrophenyl acetate (PNPA) andp-nitrophenyl caprylate (PNPC) were studied by potentiometric titration and UV spectroscopy. The values of apparent pK _a of the amines in the micellar phase, binding constants of their neutral forms, and the surface potentials of micelles were determined. Cetylpyridinium bromide accelerates the aminolysis of PNPA by factors of 3 to 8 by forming mixed micellar aggregates with the amines. The shift of pK _a values of the amines in micellar solutions is not the only factor that enhances their reactivity. The substrate specificity was found: in contrast to the reaction with PNPA, CPB accelerates (by factors of 15 to 65) or retards (by factors of 4 to 6) the aminolysis of PNPA depending on the hydrophobicity of the nucleophilic reagent. The binding constants of substrates, the rate constants in the micellar phase, and the critical concentrations of micellization were determined from the data obtained. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1333–1338, July, 1998.     

Synthesis of pyrimidino[4,5-b][1,5]benzodiazepin-2-ones and pyrimidino[1,6-a]benzimidazol-1-ones from 4-ethoxycarbonylamino-1H-1,5-benzodiazpine-3-carbonitrile via 4-(2-aminoanilino)pyrimidin-2(1H)-one-5-carbonitriles

Reactions of 4-ethoxycarbonylamino-1H-1,5-benzodiazepine-3-carbonitrile (2) with aliphatic primary amines gave 1-substituted 4-(2-aminoanilino)pyrimidin-2(1H)-one-5-carbonitriles 3. Analogous reactions of 2 with aromatic primary amines afforded 2-(2′-anilino-1′-cyanovinyl)benzimidazoles 5 and 6. Upon treatment with triethylamine, 3 underwent intramolecular cyclization to give 3-substituted 5-aminopyrimidino[4,5-b]-[1,5]benzodiazepin-2(3H,11H)-ones 8 . Heating of 3 with p-toluenesulfonic acid in ethanol gave 2-substituted pyrimidino[1,6-a]benzimidazol-1(2H)one-4-carbonitriles 9 . Reactions of 2 with hydrazines were also described. Mechanistic pathways are proposed to account for the products.     

Porous copolymer-based cation exchanger for the off-line preconcentration of aromatic amines from water

Summary A weakly polar porous copolymer and the sulfonic acid cation exchanger based on this copolymer were tested as sorbents for off-line preconcentration of aromatic amines from water. Minicolumns packed with the 1,4-di(methacryloyloxymethyl)naphthalene—divinylbenzene copolymer and the cation exchanger were used for the solid-phase extraction of polar amines. In order to study the sorption properties of these polymeric materials, the recoveries and breakthrough volumes ofp-aminophenol,o, m andp-phenylenediamine, aniline,o andp-anisidine,p-nitroaniline, ando-toluidine were determined.     

Rh-catalyzed C–N coupling of N-sulfonyl-1,2,3-trizales with secondary amines for regioselective synthesis of phenylvinyl-1,2-diamines

Abstract

An efficient and operationally simple method for the preparation of phenylvinyl-1,2-diamines by the Rh(II)-catalyzed C–N coupling of 1-sulfonyl-1H-1,2,3-triazoles with secondary amines (e.g., N-aryl glycine esters, diarylamines or 1-phenyl-2-(p-tolylamino)ethanone) via the 1,3-insertion of Rh(II)-azavinyl carbenes into sp ³ N-H bond process has been developed. The optimized conditions tolerate various functional groups and afford the diverse (Z)-phenylvinyl-1,2-diamines in good to excellent yields with high regioselectivity. The method was also successfully extended to the synthesis of functional tertiary amines having a Z configuration of the (1-aryl-2-(sulfonamido)vinyl) substituent and two aryl groups.     

Synthesis and Reactivity of Amines Containing Several Cage-like Fragments

By reaction of bicyclo[2.2.1]hept-5-en-exo- and endo-2-ylmethylamine, exo-5,6-epoxybicyclo[2.2.1]hept-exo-2-ylmethylamine and benzylamine with 1-adamantanecarbonyl chloride, 1,3-adamantanedicarbonyl dichloride, and 1,3-adamantanediacetyl dichloride amides were obtained with one, two, and three cage-like fragments that were reduced to amines by lithium aluminum hydride. The reactivity of the amines was evaluated with the use of semiempirical quantum-chemical method PM3. Derivatives of the amines were prepared by reactions with arene-sulfonyl chlorides, p-nitrobenzoyl chloride, succinic and endic anhydrides, p-toluenesulfonyl and m-tolyl isocyanates, phenyl isothiocyanate, and p-nitrophenyloxirane. The structure of the new compounds was supported by analysis of their IR and ¹H NMR spectra. The dependence of some reaction conditions was observed on the number and remoteness of the cage-like fragments from the reaction centers of the amines.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 5, 2005, pp. 695–705.Original Russian Text Copyright © 2005 by L. Kas’yan, Karpenko, A. Kas’yan, Isaev.     

Preparation of planar‐chiral multidonor phosphanylferrocene carboxamides and their application as ligands for palladium‐catalysed asymmetric allylic alkylation

Amide coupling of (S_p)‐2‐(diphenylphosphanyl)ferrocene‐1‐carboxylic acid with appropriate terminal amines mediated by 1‐hydroxybenzotriazole and a carbodiimide affords multi‐donor amides terminally functionalized with planar‐chiral (S_p)‐2‐(diphenylphosphanyl)ferrocen‐1‐yl moieties in good to excellent yields. Palladium catalysts based on these ligands efficiently promote asymmetric allylic alkylation of 1,3‐diphenylallyl acetate with in situ generated dimethyl malonate anion to give the C‐alkylated product with ees up to 93% at room temperature. Copyright © 2010 John Wiley & Sons, Ltd.     

N-Nitrosation of Secondary Amines Using p-TSA-NaNO2 as a Novel Nitrosating Agent Under Mild Conditions

A combination of p-toluenesulfonic acid (p-TSA) and sodium nitrite was used as a novel effective nitrosating agent for the N-nitrosation of secondary amines to their corresponding nitroso derivatives under mild and heterogeneous conditions in moderate to excellent yields.     

Nachweis aromatischer Amine nebeneinander

Zusammenfassung In salzsaurem Medium geben aromatische Amine mit Kaliumbromat eine Farbreaktion. Aliphatische Amine und tertiäre sowie minder nucleophile aromatische Amine geben keine positive Reaktion. Die Reaktion kann in einigen Fällen zu selektiven Nachweisen angewandt werden. Zum Beispiel ist Anilin neben Phenylhydrazin, p-Anisidin neben p-Toluidin, o-Äthylanilin neben p-Äthylanilin, N-Methylanilin neben N,N-Dimethylanilin, Hydrazobenzol neben Azobenzol bzw. Benzidin und p-Aminophenol neben o-Aminophenol nachweisbar.

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Identification of aromatic amines in presence of each other

Summary In a medium that contains hydrochloric acid, aromatic amines give a color reaction with potassium bromate. Aliphatic amines and tertiary as well as less nucleophilic aromatic amines give no positive reaction. In several instances, the reaction may be employed for selective tests, for example, aniline in the presence of phenylhydrazine,p-anisidine in presence ofp toluidine,o-ethylaniline in presence of phenylhydrazine,p-anisidine in presence ofp-toluidine,o-ethylaniline in presence ofp-ethylaniline, N-methylaniline in presence of N,N-dimethylaniline, hydrazobenzene in presence of azobenzene or benzidine, andp-aminophenol in presence ofo-aminophenol.

     

1‐Methyl‐3‐phenyl‐3‐thiocyanato‐1H,3H‐quinoline‐2,4‐dione: A novel thiocyanating agent

Under mild reaction conditions, the thiocyanato group is selectively transferred from 1‐methyl‐3‐phenyl‐3‐thiocyanato‐1H,3H‐quinoline‐2,4‐dione ( 3 ) to some nucleophiles. Aliphatic primary and secondary amines are converted to S‐cyanothiohydroxylamines, anilines afford p‐thiocyanatoanilines, Wittig reagent is thiocyanated in α‐position, and thiols are oxidized to disulfides.     

Synthesis of p-aminobenzamides of several aminopyrazolidines: Potential antiarrhythmic agents related to procainamide

Four heterocyclic amines including 1,2-diethyl-3-aminomethylpyrazolidine ( 3 ), 1-(2-aminoethyl)-2-methyl-pyrazolidine ( 5 ), 1,2-dimethyl-4-aminomethylpyrazolidine ( 7 ), and 1,2-diethyl-4-aminopyrazolidine ( 9 ) have been synthesized. Each was acylated with p-nitrobenzoyl chloride and afforded the corresponding p-nitro-benzamides 10, 12, 14 , and 16. Catalytic reduction of these nitro intermediates gave the corresponding p-aminobenzamides 11,13,15 , and 17 . The latter compounds are analogs of procainamide and two of them, 15 and 17 , were evaluated in the isolated cardiac Purkinje fiber preparation by measuring their effects on the action potential upstroke velocity.