Mass spectrometric study of the overheated vapor over nickel(II), Copper(II), and Zinc(II) <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-Ethylenebis(salicylaldiminato) complexes

A mass spectrometric study of the overheated vapor over the nickel(II), copper(II), and zinc(II) N,N′-ethylenebis(salicylaldiminato) complexes between 300 and 865°C has been carried out. Throughout this temperature range, the overheated vapor over all of the complexes contains no ions heavier than the molecular ion [MO₂N₂C₁₆H₁₄]⁺. At ∼600°C, Cu(salen) and Zn(salen) interact with the structural material of the double-chamber two-temperature effusion cell (Kh18N10T steel). The complexes are thermally very stable. The fragmentation pattern of the chelates under electron-impact ionization is metal-dependent.     

<Emphasis Type="Italic">N</Emphasis>-arylsulfinyl-1,4-benzoquinonimines

Stable N-arylsulfinyl-1,4-benzoquinonimines were synthesized by acylation of the corresponding 1,4-benzoquinone monooximes with arenesulfenyl chlorides. The process involves transformation of sulfur(II) into sulfur(IV).Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004, pp. 1340–1343.Original Russian Text Copyright © 2004 by Avdeenko, Pirozhenko, Stanovskii, Konovalova, Yusina.This study was performed under financial support by the ES INTAS program (grant no. 00 157–1999) and by the Ministry of Education and Science of Ukraine.     

3,3,3-Trifluoro-<Emphasis Type="Italic">N</Emphasis>′-(3-trifluoromethylphenyl)-1,2-propanediamine and its <Emphasis Type="Italic">N</Emphasis>-mono-and <Emphasis Type="Italic">N,N</Emphasis>-dicarboxyethyl derivatives: synthesis,protolytic and complexation properties

3,3,3-Trifluoro-N′-(3-trifluoromethylphenyl)-1,2-propanediamine (5) was synthesized by the reaction of 2-diazo-1,1,1-trifluoro-3-nitropropane or 3,3,3-trifluoro-1-nitropropene with 3-aminobenzotrifluoride followed by the reduction of the nitro group. The Michael 1,4-addition of diamine 5 to acrylic acid occurs only at the N(1) atom and affords N-mono-or N,N-dicarboxyethyl derivatives 6 and 7, depending on the reactant ratio. Protolytic equilibria 5–7 in aqueous solutions were studied by pH-potentiometry and UV spectroscopy. Only the aliphatic amino group can be protonated in an aqueous solution, while the aromatic amino group remains unprotonated even in 12 M HCl. The stability constants of transition metal (Cu²⁺, Ni²⁺, Zn²⁺) complexes with ligands 5–7 were determined by pH-potentiometric titration. The stability of the complexes and selectivity of the ligands toward Cu²⁺ ions increase with an increase in the number of N-carboxyethyl groups. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2465–2469, November, 2005.     

Synthesis and characterization of some new cobalt(II) and nickel(II) ternary complexes of <Emphasis Type="Italic">N</Emphasis>-acetyl, <Emphasis Type="Italic">N</Emphasis>-benzoyl and <Emphasis Type="Italic">N</Emphasis>-tosyl derivatives of amino acids

A series of some new cobalt(II) and nickel(II) ternary complexes of N-(acetyl)phenylalaninate (acphe), N-(acetyl)tyrosinate (actyr), N-(benzoyl)leucinate (bzleu), N-(benzoyl)phenylalaninate (bzphe), N-(tosyl)glutamic acid (tsglu), N-(tosyl)arginine (tsarg) with certain N-heterocyclic ligands such as imidazole (imi), methylimidazole (mimi), 2,2′-bipyridyl (bipy) 1,10-phenanthroline (phen) have been synthesized and characterized by elemental analyses, IR and electronic spectra. as well as thermogravimetry. The structure of the cobalt(II) N-phthaloylglycinate complex was also characterized by X-ray single crystal. It was found that the cobalt atom coordinates a 1,10-phenanthroline molecule and four water oxygen atoms, forming a distorted octahedral conformation. A molecule of N-phthaloylglycinate is connected by van der Waals contact and H-bonds.     

Nickel(II), palladium(II) and platinum(II) complexes of <Emphasis Type="Italic">N</Emphasis>-allyl-<Emphasis Type="Italic">N</Emphasis>′-pyrimidin-2-ylthiourea

Platinum(II), palladium(II) and nickel(II) complexes with N-allyl-N′-pyrimidin-2-ylthiourea were synthesized in 1:1 and 1:2 [metal:ligand] stoichiometric ratios and characterized by elemental analyses, molar conductivities, magnetic susceptibilities and by i.r., u.v.-vis., ¹H- and ¹³C-n.m.r. and mass spectra. The ¹H- and ¹³C- n.m.r. chemical shifts reveal coordination of one pyrimidine-N and sulphur atoms to Pt^II and Pd^II. The i.r. spectra indicate that the ligand behaves as a neutral monodentate towards Ni^II; coordinates via a pyrimidine-N and as a bidendate towards Pd^II and Pt^II coordinates via thione-S and a pyrimidine-N. The magnetic moments and electronic spectral data suggest a square-planar geometry for Pt^II and Pd^II complexes, a mixture of square-planar and tetrahedral geometries for the tetracoordinate Ni^II complex and octahedral for the six-coordinate one. The E.I. mass spectra of the complexes showed some isotope ion peaks of [M]⁺ and fragments containing metals; assignments of fragments containing metal ions were supported by the appearance of their peaks among isotope clusters.     

Structure and photochromism of 2-(<Emphasis Type="Italic">N</Emphasis>-acyl-<Emphasis Type="Italic">N</Emphasis>-arylaminomethylene)benzo[<Emphasis Type="Italic">b</Emphasis>]thiophen-3(2<Emphasis Type="Italic">H</Emphasis>)-ones

It was shown by electron absorption spectroscopy and X-ray diffraction analysis that steric strains in photochromic 2-(N-acyl-N-arylaminomethylene) benzo[b]thiophen-3(2H)-one molecules ortho-substituted in the N-phenyl ring increase the quantum yield of the N→O photoinduced rearrangement in accord with an increase in the steric constant of the ortho-substituent.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2151–2155, October, 2004.     

Ambidentate behavior of pentadentate <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-bis(2-hydroxyphenyl)-pyridine-2,6-dicarboxamide towards transition metal(II) salts

Complexes of Co(II), Ni(II), Cu(II), Mn(II), Zn(II) and Cd(II) with N,N′-bis(2-hydroxyphenyl)pyridine-2,6-dicarboxamide have been synthesized and characterized by elemental analysis, conductivity measurements, spectral (electronic, i.r., n.m.r. and e.p.r.), electrochemical and thermal studies. I.r. studies show that the ligand behaves in an ambidentate way. It coordinates through the pyridine nitrogen, two amide oxygens and two phenolic oxygens in the Co(II), Ni(II), and Cu(II) complexes, whereas in the Mn(II), Zn(II) and Cd(II) complexes it coordinates through the pyridine nitrogen, two uncharged amide nitrogens and two-phenolic oxygens under similar experimental conditions.     

Structure and intermolecular interactions of <Emphasis Type="Italic">N</Emphasis>-(3,5-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-4-hydroxybenzyl)thioureas

The molecular and crystal structure and the hydrogen bonding in crystal and in solutions of N-phenyl-N-(3,5-di-tert-butyl-4-hydroxybenzyl)thiourea and N-(3,5-di-tert-butyl-4- hydroxybenzyl)thiourea were studied by single crystal X-ray diffraction and IR spectroscopy. The intermolecular interactions of these compounds are essentially different.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1864–1870.Original Russian Text Copyright © 2004 by Bukharov, Litvinov, Gubaidullin, Chernova, Shagidullin, Nugumanova, Mukmeneva.This revised version was published online in April 2005 with a corrected cover date.     

Reductive Acylamination of Pyridine <Emphasis Type="Italic">N</Emphasis>-Oxide with Aminopyridines and Their <Emphasis Type="Italic">N</Emphasis>-<Emphasis Type="Italic">p</Emphasis>-Tolylsulfonyl Derivatives

Pyridine N-oxide reacts with 2- and 3-aminopyridines and their N-p-tolylsulfonyl derivatives in alkaline medium in the presence of p-toluenesulfonyl chloride to give N-p-tolylsulfonyl-2,2′- and 2,3′-dipyridylamines, respectively, as a result of reductive acylamination. In the reactions with 4-aminopyridine and 4-p-tolylsulfonyl-aminopyridine, their N-p-tolylsulfonyl- and N,N-bis(p-tolylsulfonyl) derivatives are formed, while reductive acylamination does not occur.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 128–130.Original Russian Text Copyright © 2005 by Solekhova, Kurbatov.     

Synthesis and Complexing Properties of <Emphasis Type="Italic">N,N</Emphasis>′-Bis(2-hydroxyethyl) Diaza Crown Ethers

The stability constants of complexes of 12-, 15-, and 18-membered diaza crown ethers, N,N′-dimethyl diaza crown ethers, and N,N′-bis(2-hydroxyethyl) diaza crown ethers with alkali and alkaline-earth metal ions in 95% aqueous methanol at 25°C were determined. The stability of the complexes of unsubstituted diaza crown ethers with alkali metal cations is low, probably because of stabilization of the exo,exo conformation of the ligands due to interaction of the nitrogen lone electron pairs with the solvent. The complexes with the double-charged cations are appreciably more stable. N,N′-Dimethyl diaza crown ethers form stable complexes with all the ions studied. As compared to the dimethyl derivatives, N,N′-bis(2-hydroxyethyl) diaza crown ethers form more stable complexes with the Na⁺, K⁺, Ca²⁺, Sr²⁺, and Ba²⁺ ions, which is due to participation of the side hydroxyethyl groups in the coordination.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 665–669.Original Russian Text Copyright © 2005 by Kulygina, Vetrogon, Basok, Luk’yanenko.     

Chelates and corrosion inhibition of newly synthesized Schiff bases derived from <Emphasis Type="Italic">o</Emphasis>-tolidine

New copper(II), nickel(II), iron(III) and palladium(II) Schiff base complexes derived from o-tolidine and selected aldehydes, namely salicyaldehyde and 2-hydroxynaphthaldehyde have been synthesized and characterized by a combination of elemental analyses, magnetic moments, spectral (u.v.–vis., i.r.) and thermal (tg, dtg) mesurements. The corrosion inhibition of aluminium and copper in 1 M HCl and chromium–nickel steel in crude oil using N,N′bis(salicyledene)-o-tolidine have been studied by weight loss method.     

Adsorption-luminescence determination of copper concentration using silica gel chemically modified with <Emphasis Type="Italic">N</Emphasis>-(1,3,4-thiadiazol-2-thiol)-<Emphasis Type="Italic">N</Emphasis>′-propylurea groups

Silica gel chemically modified with 1,3,4-thiadiazol-2-thiol groups recovered 99% of the copper(II) from solutions of pH 4–6; the adsorption equilibrium was attained in no more than 5 minutes. During irradiation with ultraviolet light, a yellow-orange luminescence (λ_max = 575 nm) of surface copper complexes appeared in the phase of adsorbent cooled to 77 K; it was used as an analytical signal in the procedure for the low-temperature adsorption-luminescence determination of copper concentration. The detection limit was 0.3 μ g/0.1 g adsorbent. The calibration graph was linear up to 50 μg/0.1 g adsorbent. The determination of copper concentration is not affected by 10000-fold amounts of Zn(II), Cd(II), Mn(II), Co(II), Ca(II), Mg(II), and Al(III) and 300-fold amounts of Fe(III). The procedure was used to determine copper concentration in natural and technogenic waters.     

UV/Vis Spectroscopic Properties of <Emphasis Type="Italic">N</Emphasis>-(2′-Hydroxy-4′-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-dimethyl-aminobenzylidene)-4-nitroaniline in Various Solvents and Solid Environments

Summary.  N-(2′-Hydroxy-4′-N,N-dimethylaminobenzylidene)-4-nitroaniline [HDBN] has been used as a model for investigating intra- and intermolecular D–A (donor–acceptor) interactions in various environments by means of UV/Vis spectroscopy. UV/Vis spectra of HDBN have been measured in various solvents, ethanolic solutions of different pH, adsorbed on silica, and in the solid state. A bathochromic shift of ν_max is observed with increasing the dipolarity/polarizability and HBD (hydrogen bond donor) capacity of the solvent, which is described by means of a multiple LSE (linear solvation energy) relationship in terms of the empirical Kamlet-Taft solvent polarity parameters. The adsorption of HDBN on Aerosil^? 300-silica particles in non-HBA (hydrogen bond acceptor) solvents is explained in the same sense. Mobile protons and sol–gel entrapping cause a hypsochromic shift due to protonation of the lone electron pair of the 4′-N,N-dimethylamino group. Hydroxide ions attack the 2′-hydroxy group which causes a bathochromic shift. A strong intramolecular hydrogen bond between the 2′-hydroxyl hydrogen and the imine nitrogen atom is present in the solid-state structure causing an unprecedented bathochromic shift. Corresponding author. E-mail: stefan.spange@chemie.tu-chemnitz.de Received July 8, 2002; accepted (revised) September 30, 2002     

Synthesis and antibacterial activity of (<Emphasis Type="Italic">N</Emphasis>-1-methylglucosaminocarbonothioyl)-4-bromobenzamide chelate complex with copper(II) sulfate

Reactions of (N-1-methylglucosaminocarbonothioyl)-4-bromobenzamide with copper(II) sulfate in the ratios 1:1 and 2:1 affords the corresponding chelate complexes of the metal. Their structure was proved by high resolution mass spectrometry. The complex of (N-1-methylglucosaminocarbonothioyl)-4-bromobenzamide with copper(II) sulfate (ratio 1:1) exhibits pronounced antibacterial activity.     

Energy of Formation of an Acyclic <Emphasis Type="Italic">N</Emphasis>-Methyltrifluoromethanesulfonamide Dimer

The energy of formation of an open-chain N-methyltrifluoromethanesulfonamide dimer stabilized by the N-H⋯O=S hydrogen bond is 20.1 kJ mol⁻¹ (CH₂Cl₂). This value exceeds by ∼12 kJ mol⁻¹ the energy of formation of cyclic secondary methanesulfonamide self-associates per hydrogen bond.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 2, 2005, pp. 295–298.Original Russian Text Copyright © 2005 by Chipanina, Sherstyannikova, Sterkhova, Turchaninov, Shainyan.     

Intermolecular interactions in orthophosphoric acid-<Emphasis Type="Italic">N,N</Emphasis>-dimethylformamide system according to viscometric data

The viscosity of an orthophosphoric acid—N,N-dimethylformamide system was measured in the whole region of compositions at 298–338 K. An excess viscosity of the system was analyzed by the data obtained using different model concepts. Calculations suggested that strong intermolecular interactions and the formation of complexes (H₃PO₄)₂·DMF occur in the system. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2252–2256, October, 2005.     

<Emphasis Type="Italic">N</Emphasis>-benzyl derivatives of valine esters

The reactions of methyl and ethyl esters of valine with m-bromobenzaldehyde and p-chlorobenzaldehyde in absolute methanol in the presence of magnesium sulfate yielded the corresponding azomethines (CH₃)₂CHCH(COOR¹)N=CHR² (R¹ = CH₃, C₂H₅; R² = 3-BrC₆H₄, 4-ClC₆H₄); their reduction with sodium borohydride gave N-benzyl derivatives of valine esters, (CH₃)₂CHCH(COOR¹)NHCH₂R².Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1855–1857.Original Russian Text Copyright © 2004 by Yakubovich, Zhavnerko, Shirokii, Knizhnikov.This revised version was published online in April 2005 with a corrected cover date.     

Synthesis of benzo[<Emphasis Type="Italic">f</Emphasis>]quinoline derivatives by condensation of <Emphasis Type="Italic">N</Emphasis>-arylmethylene-2-naphthylamines with acetylcyclohexane and 1-acetylcyclohexene

N-Arylmethylene-2-naphthylamines react with acetylcyclohexane and 1-acetylcyclohexene under mild conditions to afford 2-aryl-2-(2-naphthylamino)ethyl cyclohexyl and 1-cyclohexenyl ketones, respectively. Under more severe conditions (110°C), the reaction is accompanied by cyclization with formation of 3-aryl-1-cyclohexyl(or 1-cyclohexenyl)benzo[f]quinolines. Proper choice of the amount of catalyst, temperature, and reaction time allows isolation of intermediate 3-aryl-1-cyclohexyl(or 1-cyclohexenyl)-3,4-dihydrobenzo[f]quinolines.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1878–1883.Original Russian Text Copyright © 2004 by Grachek.This revised version was published online in April 2005 with a corrected cover date.     

Functionalyzed polyampholytes on the basis of copolymers of <Emphasis Type="Italic">N,N</Emphasis>-diallyl-<Emphasis Type="Italic">N,N</Emphasis>-dimethylammonium chloride and maleic acid

Polyampholytes were prepared by radical copolymerization of N,N-diallyl-N,N-dimethylammonium chloride and maleic acid. The esterification and subsequent hydrazinolysis permitted to introduce hydrazide groups capable of formation of the coordination bond with copper ions. The formation of complex between the hydrazide groups of polyampholyte and Cu²⁺ ions was established by electronic spectroscopy. It was shown that the coordination of two hydrazide groups in the complex was hampered because of the polymeric nature of the ligand. It is shown that the created functionalized polyampholytes exhibit fungiostatic activity. The highest inhibiting effect on the growth of the pathogenic fungus Fusarium oxysporum is observed for complexes of the hydrazide-containing polyampholytes with Cu²⁺ ions.     

Facile synthesis and biological evaluation of novel fluorine-containing <Emphasis Type="Italic">N</Emphasis>-nitro-<Emphasis Type="Italic">N</Emphasis>′-substituted phenylurea

Twenty-two novel N-nitro-N′-substituted phenyl-N-(2,6-dibromo-4-fluorophenyl)urea derivatives were designed and synthesized via a simple and convenient BTC ‘one-pot’ procedure using DMAP as the catalyst. The structures of all newly synthesized compounds were confirmed by IR, ¹H NMR, and elemental analysis, and a part has been identified by ¹³C NMR. The preliminary bioassay indicates that the target compounds possesses moderate herbicidal activity against Sorghum sudanense. However, some of the title compounds presented high plant growth regulating activity against rape.