Solvent-free synthesis of 1-amidoalkyl-2-naphthols using magnetic nanoparticle-supported 2-(((4-(1-iminoethyl)phenyl)imino)methyl)phenol Cu (II) or Zn (II) Schiff base complexes

Two magnetic nanoparticle-supported 2-(((4-(1-iminoethyl)phenyl)imino)methyl)phenols were successfully synthesized, characterized, and applied in the one-pot three-component reaction of substituted benzaldehydes, 2-naphthol, and amides for synthesis of 1-amidoalkyl-2-naphthols. These three-component processes occurred under solvent-free reaction conditions at 80 °C. The magnetically recoverable supported Schiff base metal catalysts can be reused several times in the model reaction. The synthesized catalysts are also easily separated from the reaction mixture by applying an external magnet. This procedure offers the advantages of simple, operational procedure as well as no use of hazardous organic solvents.

     

Synthesis of 4-{{[(Isopropyloxy)methylphosphoryloxy]imino}methyl}-1-methylpyridinium Iodide and Its Characterisation

Oximes are used in the therapy of organophosphate poisoning. They form an interaction product with the organophosphate which is claimed to be more toxic than the organophosphate itself. We have synthesized one of these compounds which would be formed by the reaction of pyridine-4-carbaldehyde oxime methiodide with sarin (GB). Thus, reaction of oxime 1 with sarin chloridate ( 2 ), yielded 4-{{[(isopropyloxy)methylphosphoryloxy]-imino}methyl}-1-methylpyridinium iodide ( 4 ) which was characterized by NMR spectroscopy and X-ray crystallography.     

Sulfonated 1-(2-pyridylazo)-2-naphthols and 2-(2-pyridylazo)-1-naphthols as spectrophotometric reagents: Determination of nickel

Three sulfonated 1-(2-pyridylazo)-2-naphthols and six sulfonated 2-(2-pyridylazo)-1-naphthols were synthesized, and their application to the spectrophotometric determination of metals was studied. The acidity constants of the reagents and the stability constants of the nickel chelates are reported, and the relationship between their properties and the position of the sulfonic acid group is discussed. 1-(2-Pyridylazo)-2-naphthol-6-sulfonic acid (PAN-6S) and 1-(2-pyridylazo)-2-naphthol-7-sulfonic acid (PAN-7S) are sensitive and selective reagents for nickel. The determination of nickel in the presence of cobalt with PAN-6S is described. Extraction of the chelate as the ion-pair with tetraphenylarsonium ions into chloroform is suitable for the determination of 1–10 μg Ni at 570 nm; the molar absorptivity is 56 000 l mol^-1 cm^-1, and interferences are easily avoided.     

Molecular structures of methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-5-carboxylate and methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-3-carboxylate

The structure of methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-5-carboxylate is determined by X-ray crystallography and further used to elucidate the structure of methyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)methyl]-1-methyl-1H-pyrazol-3-carboxylate, using the data of homo- and heteronuclear 2D NMR correlation spectroscopy.     

Solvent- and temperature-controlled in situ ligand reactions mediated by Cu(II) and 3'-[(E)-{[(1S,2S)-2-aminocyclohexyl]imino}methyl]-4'-hydroxy-4-biphenylcarboxlic acid

Three new compounds, CuL, CuL', and Cu(2)O(2)L'(2) (H(2)L = 3'-[(E)-{[(1S,2S)-2-aminocyclohexyl]imino}methyl]-4'-hydroxy-4-biphenylcarboxlic acid, H(2)L' = 3'-[(E)-{[(1S,2S)-2-aminocyclohexyl]imino}methyl]-4'-hydroxy-5'-nitro-4-biphenylcarboxlic acid, H(2)L' = 3'-(N,N-dimethylamino methyl)-4'-hydroxy-4-biphenylcarboxlic acid), were selectively synthesized through a controlled in situ ligand reaction system mediated by copper(II) nitrate and H(2)L. Selective nitration was achieved by using different solvent mixtures under relatively mild conditions, and an interesting and economical reductive amination system in DMF/EtOH/H(2) O was also found. All crystal structures were determined by single-crystal X-ray diffraction analysis. Both CuL and CuL' display chiral 1D chain structures, whereas Cu(2)O(2)L'(2) possesses a structure with 13×16?? channels and a free volume of 41.4?%. The possible mechanisms involved in this in situ ligand-controlled reaction system are discussed in detail.     

Electrochemical reduction of benzenesulphenyl chloride in aprotic solvents

The cathodic behaviour of benzenesulphenyl chloride has been studied at a platinum electrode in acetonitrile by using cyclic voltammetry and controlled potential electrolysis. It has been evidentiated that PhSCl gives rise, in an one-electron reduction process, to PhSSPh and Cl^? according to $2PhSCl+2{\mathit{e}}^{?}\to PhSSPh+2{Cl}^{?}$ The chloride ions so generated catalyze the subsequent hydrolysis of PhSCl caused by traces of water present in the organic solvent, i.e. $2PhSCl+H_{2}O\stackrel{{Cl}^{?}}{\to }PhSOSPh+2HCl$ which is concomitant with the electrodic reaction and hence accounts for the overall n_e value lower than one. The same results have been obtained in nitromethane while in dimethyl-formamide the above reported hydrolysis reaction seems to be catalyzed by the solvent itself.     

Radical nucleophilic substitution of 2-(4-halophenyl)-2-methyl-1-chloropropane with enolate ions of ketones

The photoinitiated reaction of 2-(4-halophenyl)-2-methyl-1-chloropropane 2a,b (halogen=Br, I, respectively) with the anions of pinacolone (3a) and acetophenone (3b) either in DMSO or in liquid ammonia are reported. In DMSO, the main reaction is the SRN1 nucleophilic substitution at the aromatic (Csp2-halogen) center with substitution or reduction at the aliphatic (Csp3-Cl) one. In liquid ammonia, the main reaction is substitution at the aromatic C-halogen site. This difference in product distribution is ascribed to modifications in the rate constant of Csp3-Cl dissociation of the radical anions proposed as intermediates in going from DMSO (rt) to liquid NH3 (-33 degrees C).     

Synthesis of 2([Methyl-5-[(E)-2-aryl-1-ethenyl]-4-isoxazolyl]imino)-1,3-thiazolan-4-ones and Their Mannich Bases

Isoxazolyl chloroacetamides (2) were obtained from 4-amino-3-methyl-5-styrylisoxazoles (1) on reaction with chloroacetyl chloride. Cyclocondensation of 2 with NH₄SCN yielded 2([-methyl-5-(E)-2-aryl-1-ethenyl]-4-isoxazolylimino)-1,3-thiazolan-4-ones(3). Mannich reaction of 3 with formaldehyde and secondary amines gave isoxazolyl thiazolidinone Mannich bases (4 and 5).     

Synthesis of 1-halophenyl 4-(2-imidazolyl)-1-butanones and 5-(2-imidazolyl)-1-pentanones and their ketalization with glycerol

An alternate synthesis of 1-(2,4-dichlorophenyl)-4-(2-imidazolyl)-1-butanones 5d is presented after 1-[(dimethylamino)methyl- and 1-methyl]-2-lithioimidazole failed to be substituted satisfactorily by 2-(2,4-dichlorophenyl)-2-(3-iodopropyl)-1,3-dioxolane ( 3b ). The Pinner addition of ethanol to 2-(2,4-dichlorophenyl)-2-(3-cyanopropyl)-1,3-dioxolane yielded the corresponding imidate which was reacted with 1-amino-2,2-dimethoxyethane to form an amidine. Hot dilute hydrochloric acid converted this ami-dine to the 2-imidazolyl ketone 5b . Syntheses of homologous 1-(4-chloro- and 2,4-dichlorophenyl)-4-(2-imidazolyl)-1-pentanones 20 are described. Ketalizations of 5 and 20 with glycerol formed imidazolyl 1,3-dioxolanyl alcohols. Selective N- and O-alkylations of some of these imidazolyl alcohols are described.     

Synthesis of substituted in benzene ring 4-[(2-aminophenyl)thio]-, 4-[(2-mercaptophenyl)amino]-2-methylquinolines and (4E)-4-[(2-mercaptophenyl)imino]-2-methyl-1,4-dihydroquinolines

By a reaction of 2-methyl-4-chloroquinolines with o-mercaptoaniline under various conditions synteses were performed of substituted in the benzene ring 4-[(2-aminophenyl)thio]-2-methylquinolines and (4E)-4-[(2-mercaptophenyl)imino]-2-methyl-1,4-dihydroquinolines that were respectively by isomerization or rearrangement converted into 4-[(2-mercaptophenyl)amino]-2-methylquinolines.     

Electrochemical Synthesis of 2-(2-Chlorophenyl)-2-[(3,4- dihydroxyphenyl)(methyl)amino]cyclohexanone

Russian Journal of Electrochemistry - Electrochemical oxidation of catechol has been studied in the presence of ketamine as a drug in phosphate buffer solution mixed with ethanol using voltammetric...     

Electrochemical reduction of 1, 4-dihydropyridine-3, 5-dicarboxylic acid derivatives in an aprotic medium

The polarographic reduction of 1, 4-dihydropyridine-3, 5-dicarboxylic acid derivatives in dimethylformamide was studied. It is shown that the first diffusion waves of these compounds are irreversible one-electron waves and correspond to electrical reduction of the C=C bond of the conjugated system of the 1, 4-dihydropyridine ring to give a tetrahydro derivative. In the case of pyridine-3, 5-dicarboxylic acid esters partial dimerization of the resulting freeradical products occurs along with electron transfer. It is shown that the introduction of alkoxycarbonyl substituents in 2, 6-methyl and 3, 5-methoxycarbonyl groups and in the 4 position and of a carboxyl group in the 4 position facilitates the electrical reduction of the 1, 4-dihydropyridine ring. The introduction of a methyl group in the 4 position hinders reduction of the ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 641–646, May, 1978.