Complexation and extraction properties of <Emphasis Type="Italic">N′,N′</Emphasis>-dibutyloctanohydrazide

A new extractant for copper(ii) extraction, viz., N′,N′-dibutyloctanohydrazide, was synthesized. Its acid-base, extraction, and complexation properties were studied. The introduction of two butyl substituents into the hydrazide group weakens the acidic properties of the compound synthesized compared to the unsubstituted hydrazide, shifts the region of efficient copper(ii) extraction from an acidic medium to weakly acidic and ammonia media, and forms an uncharged extractive copper complex. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 380–384, February, 2008.     

Directed Aminomethylation of Pyrrole,Indole, and Carbazole with <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N′</Emphasis>,<Emphasis Type="Italic">N′</Emphasis>-Tetramethylmethanediamine

Catalytic aminomethylation of pyrrole and indole with N,N,N′,N′-tetramethylmethanediamine in the presence of 5 mol % of ZrOCl₂·8H₂O proceeds selectively at the positions 2, 5 of pyrrole and 1, 3 of indole. Carbazole under the same conditions affords 3-formyl-9-aminomethyl derivative. The reaction in the presence of 5 mol % of K₂CO₃ occurs as monoaminomethylation: for pyrrole at the position 2, for indole at the position 3, and for carbazole at the nitrogen atom of the substrate. Water-soluble 1,1′-(1H-pyrrole-2,5-diyl)bis(N,N-dimethylmethanamine) exhibits a fungistatic activity with respect to phytopathogenic fungi Rhizoctonia solani.     

Copper(II) complexing with <Emphasis Type="Italic">N′,N′</Emphasis>-diethylbenzohydrazide

Copper(II) complexing with N′,N′-diethylbenzohydrazide (DEBH) in aqueous isopropanol was studied. The formation of cationic complexes with the ratio [Cu²⁺]: [DEBH] = 1: 1 and 1: 2 in week acid solution and an uncharged complex with the ratio [Cu²⁺]: [DEBH] = 1: 2 in neutral and alkaline solutions was established. Their stability constants K _st were determined. The complexes were isolated in a solid state and characterized by IR spectroscopy and elemental analysis for copper.     

X-ray and computational structural study of neutral <Emphasis Type="Italic">bis</Emphasis>(<Emphasis Type="Italic">N,N,N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-tetramethylthiophosphoramidoyl)-methylamine

The structure of bis(N,N,N′,N′-tetramethylthiophosphoramidoyl)-methylamine 1 has been determined by single-crystal X-ray diffraction. The compound 1 crystallizes in the monoclinic system, with a space group P2₁/c, a = 11.836(2) Å, b = 11.659(2) Å, c = 12.796(5) Å and β = 95.28(3)°, V = 1758.3(5) Å³ and Z = 4. The X-ray crystallographic data have been assessed by semi-empirical and ab-initio density functional theory and by Hartree–Fock molecular orbital methods. A comparative study of the results of the different methods is given.     

Synthesis and structure of the cobalt(II) coordination compounds with <Emphasis Type="Italic">N,N</Emphasis>-dimethyl-<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-dimethylthiocarbamoylsulfenamide

The CoLX₂ complexes were obtained by the reaction of N,N-dimethyl-N′,N′-dimethylthio-carbamoylsulfenamide (L) with CoX₂ (X = Cl, Br, I, NCS). The complexes were investigated by elemental and X-ray analysis, IR, ¹H NMR, and electron spectroscopy, conductometry, magnetochemistry, thermogravimetry. It is found that these compounds are high-spin complexes of pseudotetraedral structure with bidentate coordination of L through the thione sulfur atom and sulfenamide nitrogen atom.     

Copper(II) complexation and extraction with 2-ethylhexanoic acid <Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-dialkylhydrazides

2-Ethylhexanoic acid N′,N′-dibutylhydrazide (DBH) and N′,N′-diheptylhydrazide (DHH) were synthesized. The existence regions of copper (II), zinc(II), nickel(II), and cobalt(II) complexes formed upon extraction with DBH in kerosene were studied. The neutral complex ML₂ extracted over a wide pH range (from pH ～ 6 to \(c_{NH_3 } \) ～ 4 mol/L) is formed only by copper(II), while zinc(II), nickel(II), and cobalt(II) react with DBH to yield precipitates that float at pH 7–9, 9–10.5, and 9.5–11, respectively. On the basis of IR spectra, elemental analysis, and properties, a structure was suggested for the CuL₂ complex with DBH. The DBH and DHH complexes with copper(II) are readily stripped with H₂SO₄ and H₂SO₄ + CuSO₄ solutions. The capacity of a 1.5 mol/L DHH in kerosene with respect to copper(II) is 26 g/L.     

Kinetics of the Decomposition of α-Phenylethyl Hydroperoxide in the Presence of <Emphasis Type="Italic">N,N,N′,N′</Emphasis>-Tetramethyl-<Emphasis Type="Italic">para</Emphasis>-Phenylenediamine

It is found that the tertiary amine N,N,N′,N′-tetramethyl-para-phenylenediamine (TMPD) causes the decomposition of α-phenylethyl hydroperoxide (ROOH), and the interaction between the components occurs in accordance with a complicated rate law. It is demonstrated that more than 30 hydroperoxide molecules (n) can be degraded at a molecule of TMPD; this fact suggests that the amine has a catalytic effect on the process. The value of n increases with the [ROOH]₀/[TMPD]₀ ratio. The initial rates of consumption of ROOH and TMPD linearly increase with the initial concentrations of both of the reactants. The apparent rate constant of the reaction is k = 0.4 l mol^?1 s^?1 (393 K), as calculated from the initial rates of ROOH consumption. As a result of the interaction, TMPD is converted into an inhibitor. The rate constant of the reaction of this inhibitor with ethylbenzene peroxy radicals is about 2 × 10⁴ l mol^?1 s^?1.     

Transformations of the extra ring in pheophorbide <Emphasis Type="Italic">a</Emphasis> methyl ester in the reaction with <Emphasis Type="Italic">N,N,N′,N′</Emphasis>-tetramethylmethanediamine

The reaction of N,N,N′,N′-tetramethylmethanediamine with pheophorbide a methyl ester gave the corresponding 13″-dimethylaminomethyl derivative and 13-N,N-dimethylamide derivative of chlorin e ₆ having a methyl acrylate moiety in the 15-position. Conditions were found for the synthesis of the latter both directly from pheophorbide a methyl ester and from its aminomethylation product. Probable mechanisms of the examined reactions were proposed.     

<Emphasis Type="Italic">N′,N′</Emphasis>-dialkylhydrazides and their protonated forms: <Emphasis Type="Italic">ab initio</Emphasis> calculations and studies by physical methods

RHF/6-31G(d) and MP2/6-31G(d) quantum-chemical calculations of N′,N′-dimethylethanohydrazide molecule and also MP2/6-31G(d) calculations of its protonated forms were performed. With the use of IR and ¹H NMR spectroscopy the series of N′,N′-dialkylhydrazides and their salts with HCl and H₂SO₄ were studied. The position of proton addition was determined. The experimental results were compared with the calculated findings.     

Thermodynamics of nickel(II) complexing with trimethylenediamine-<Emphasis Type="Italic">N,N,N′,N′</Emphasis>-tetraacetic acid

The heats of nickel(II) trimethylenediaminetetraacetate formation were determined by direct calorimetry at 298.15 K and ionic strength I =0.1, 0.5, and 1.0 (KNO₃). The corresponding thermodynamic characteristics were calculated. The results were compared to literature data on the related compounds.     

<Emphasis Type="Italic">N′, N′</Emphasis>-dialkylhydrazides as inhibitors of acid corrosion of steel

The effect of N′,N′-dialkylhydrazides of aliphatic carboxylic acids of the general formula C₄H₉CH(C₂H₅)C(O)NHN(R)₂ on the corrosion behavior of St.20 steel in 0.1 and 1 M HCl was studied by electrochemical and gravimetric methods.     

Cyclization of the substituted <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">Ortho</Emphasis>-cyclopropylphenyl)-<Emphasis Type="Italic">N′</Emphasis>-aryl ureas and thioureas in the gas phase and solution

Electron ionization (EI), chemical ionization (CI), tandem mass spectrometry, high-resolution measurements, and labeling studies as well as quantum chemical calculations were used to understand the behavior of the molecular radical cations (EI) and protonated molecules (CI) of substituted N-(ortho-cyclopropylphenyl)-N'-aryl ureas and N-(ortho-cyclopropylphenyl)-N'-aryl thioureas in a mass spectrometer. Fragmentation schemes and possible mechanisms of primary isomerization were proposed. According to the fragmentation pattern, formation of the corresponding benzoxazines and benzothiazines was considered as the major process of isomerization of the original M(+.) and MH(+), although some portions of these ions definitely transformed into other structures. The treatment of N-(ortho-cyclopropylphenyl)-N'-phenyl urea and N-(ortho-cyclopropylphenyl)-N'-phenylthiourea in solution with strong acids formed predicted 4-ethyl-N-phenyl-4H-3,1-benzoxazin-2-amin and 4-ethyl-N-phenyl-4H-3,1-benzothiazin-2-amine as principal products.     

Vanadium(V) extraction from sulfuric and hydrochloric acid solutions with hydrazides and <Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-dialkylhydrazides of Versatic acids

Conditions of vanadium(V) extraction from sulfuric and hydrochloric acid solutions with kerosene solutions of hydrazides and N’,N’-dimethylhydrazides derived from fractions of Versatic 10 and Versatic 1519 branched higher carboxylic acids were studied. Conditions of vanadium(V) back extraction from organic phase were studied. For diluted acid solutions, ratios were found to be [V(V)]: [reagent] = 1: 1 and 1: 5 for sulfuric acid media and 1: 1 and 1: 8 for hydrochloric acid media.     

Synthesis,characterization, and biological activities of oxovanadium(IV) and cadmium(II) complexes with reduced Schiff bases derived from <Emphasis Type="Italic">N,N′</Emphasis>-<Emphasis Type="Italic">o</Emphasis>-phenylenebis(salicylideneimine)

New oxovanadium(IV) and cadmium(II) complexes with reduced Schiff bases derived from N,N′-o-phenylenebis(salicylideneimine) have been synthesized and characterized using infrared and UV-visible spectra, ESR, and thermogravimetry. The complexes were identified as [ML] · (H₂O) species, where deprotonated ligands are coordinated to metal through N₂O₂ donor atoms. Antioxidant activity of the ligands and complexes was evaluated, revealing that the complexes exhibit a higher scavenging activity than the corresponding ligands. The prepared cadmium complexes showed slightly higher activity than the vanadium ones. Antifungal activity was tested against different human fungi including yeasts of the Candida genus (C. albicans and C. glabrata) and an opportunistic mould Aspergillus fumigatus. The oxovanadium complexes exhibited a very low activity toward C. albicans while the cadmium ones showed a significant growth inhibition of all the fungi tested; mainly of A. fumigatus though this mould is poorly susceptible to current antifungal agents like Itraconazole.     

<Emphasis Type="Italic">N</Emphasis>′-tetrazolylmethoxyl derivatives of <Emphasis Type="Italic">N</Emphasis>-methyldiazene <Emphasis Type="Italic">N</Emphasis>-oxides

A preparation method was developed for previously unknown tetrazole derivatives containing in the 1, 2, and/or 5 positions of the tetrazole ring N-methyldiazene-N-oxide-N′-oxymethyl groups.     

Synthesis and crystal and molecular structures of <Emphasis Type="Italic">N,N</Emphasis>′-methylenedipyridinium tetrachlorozincate(II) and <Emphasis Type="Italic">N,N</Emphasis>′-methylenedipyridinium tetrachlorocadmate(II)

Treatment of N,N′-methylenedipyridinium dichloride [C₅H₅N-CH₂-NC₅H₅]Cl₂ with MCl₂ (M = Zn or Cd) in aqueous solution gives the organic-inorganic hybrid ionic compounds [C₅H₅N-CH₂-NC₅H₅] · [MCl₄]. Both complex salts were fully characterised by multinuclear NMR spectroscopy, elemental analysis, and their molecular structures confirmed by powder X-ray diffraction studies. The most striking feature in both solid state structures was the presence of the C…Cl-M short contacts between the organic [C₅H₅N-CH₂-NC₅H₅] dication and inorganic [MCl₄] anion, which led to different crystal packing. For [C₅H₅N-CH₂-NC₅H₅]·[ZnCl₄], the C…Cl-Zn interactions led to the alternating arrangement of [C₅H₅N-CH₂-NC₅H₅]²⁺[ZnCl₄]²⁻ to form 1-D chains in the direction [010], and each individual chain had a two-fold rotational axis along the b axis, while for [C₅H₅N-CH₂-NC₅H₅] · [CdCl₄] the C…Cl-Cd associations gave 2-D network. In both solid state structures, the presence of Cl-ring centroid distances gave a strong indication of some form of Cl-π interactions.     

1,3-Diamino-2-Hydroxypropane-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′,<Emphasis Type="Italic">N</Emphasis>′-Tetraacetic Acid: Crystal and Molecular Structures

The synthesis, IR spectroscopic study, and X-ray diffraction analysis (CIF file CCDC no. 1574078) are carried out for 1,3-diamino-2-hydroxypropane-N,N,N′,N′-tetraacetic acid (I). The structural units of a crystal of compound I are (H_4.5HPdta)^0.5– anions, (H_5.5HPdta)^0.5+ cations, and molecules of water of crystallization joined by a branched network of hydrogen bonds: strong intermolecular O–H…O and intramolecular N–H…O bonds.     

Reaction of 1-hetaryl-4-phenylthiosemicarbazides with <Emphasis Type="Italic">N,N′</Emphasis>-dicyclohexylcarbodiimide

1,2,4-Triazolo[3,4-b][1,3]benzothiazole, 1,2,4-triazolo[4,3-a]pyrimidine, and thieno[3,2-e][1,2,4]-triazolo[4,3-a]pyrimidine derivatives were synthesized by reactions of 1-hetaryl-4-phenylthiosemicarbazides with N,N′-dicyclohexylcarbodiimide.