Previous studies have established that the extended coordination model of solvation can satisfactorily account for the variation in the transfer enthalpies of solutes in mixed-solvent systems. The ...model parameter relating to the solute-induced disruption of the solvent structure shows a marked dependence on the nature of the mixed solvent. In the present paper we report the transfer enthalpies of acetonitrile from water to aqueous methanol, ethanol and dimethylsulphoxide (DMSO) systems. Analysis of these in terms of the extended coordination model confirms both the model's ability to account for the experimental data, and the variability of the structural disruption parameter. The solvation parameters recovered from the analyses indicate that the net effect of acetonitrile on the solvent structure is a breaking of solvent–solvent bonds. The extent of bond breaking of the solvent increases from MeOH to EtOH.
In this paper, the nanodithiocarbamate (DTC) complexes have been prepared by the reaction between DTC and metal salt under ultrasound irradiation. The DTC complex nanoparticles have been prepared in ...water. The antimicrobial activity of nanoparticles derivatives are tested against microorganism, and compared with non-nano conditions. The resulting nanoparticles were characterised by X-ray diffraction and scanning electron microscopy.
Examination of the solid state infrared spectra of the tetramethylammoniumcation in salts shows correlation of infrared spectral properties with C–H···X hydrogen bonding and crystal habits in these ...tetramethylammonium salts. The IR predicted crystal habits are comprised by experimental and theoretical data. A good relation between three data has been found. The C–H stretching region characteristic hydrogen bonding shifts in the above salts. In this research three complexes of tetramethylammoniumcation have been synthesized and the structures of them have been analyzed by correlation of vibrational data with crystal structures. These correlation shows that crystal symmetry (Tetrahedral), cation distortion (undistorted), site symmetry (D2d), unite cell symmetry (D4h7) for (CH3)4NPF6 and crystal symmetry (Tetrahedral), cation distortion (distorted), site symmetry (D2d), unite cell symmetry (D4h7) for (CH3)4NOH and crystal symmetry (Tetrahedral), cation distortion (undistorted), site symmetry (D2d), unite cell symmetry (D4h7) for (CH3)4NF.
A new Cd(II) complex with 4′-chloro-2,2′ : 6′,2″-terpyridine (Cltpy), Cd(Cltpy)(NO
3
)
2
(H
2
O)
0.45
(CH
3
OH)
0.55
, has been synthesized and characterized by CHN elemental analysis,
1
H-NMR,
13
...C-NMR, IR spectroscopy, and structurally analyzed by X-ray single-crystal diffraction. The single-crystal X-ray analyses show that the coordination number is seven with three terpyridine (Cltpy) N-donors, three oxygen atoms of two nitrates and one oxygen atom of methoxy/water. The antibacterial activities of Cltpy and its Cd(II) complex are tested against different bacteria. The free ligand has considerable activity against Staphylococcus aureus, Bacillus anthracis, and Pseudomonas aeruginosa (inhibition zones ≥ 20 mm), but has moderate activity against Escherichia coli and Streptococcus pyogenes (inhibition zones ≤ 15 mm). In comparison with free Cltpy ligand, its complex has more activity against Klebsiella pneumonia, S. aureus, and B. anthracis (inhibition zones ≥ 30 mm), but is inactive against P. aeruginosa and S. pyogenes. The quantitative assays gave minimal inhibitory concentration values in the range 6.25-100 mg mL
−1
that confirmed the above results. Against K. pneumonia and S. aureus, antibacterial activity of the complex is higher than Cltpy ligand.
Using the water eliminated mechanism, reactions of 4-pyridinecarboxylic acid hydrazide and salicylaldehyde, benzaldehyde, cinnamaldehyde, and formaldehyde afforded the corresponding ...N(4)(E)-1-(2-hydroxyphenyl) methylidene (NHPM), N(4)-(E)-2-phenylethylidene (NPI), N(4)(E,2E)-3-phenyl-2-propenylidene (NPPI), and N(4)(E) ethylidene (NEI) isonicotinohydrazide, in high yields, after several minutes, as reported. These new compounds have shown antitumor activity against two kinds of cancer cells, which are K562 (human chronic myeloid leukemia) and Jurkat (human T lymphocyte carcinoma).
Using the water eliminated mechanism, reactions of 4-pyridinecarboxylic acid hydrazide and salicylaldehyde, benzaldehyde, cinnamaldehyde, and formaldehyde afforded the corresponding N 4 ...(E)-1-(2-hydroxyphenyl) methylidene (NHPM), N 4 -(E)-2-phenylethylidene (NPI), N 4 (E,2E)-3-phenyl-2-propenylidene (NPPI), and N 4 (E) ethylidene (NEI) isonicotinohydrazide, in high yields, after several minutes, as reported. These new compounds have shown antitumor activity against two kinds of cancer cells, which are K562 (human chronic myeloid leukemia) and Jurkat (human T lymphocyte carcinoma).
A mild and efficient method for the oxidative coupling of thiols by tripropylammonium chlorochromate in solution and in solution under microwave radiation is reported. Tripropylammonium ...chlorochromate is an efficient and new reagent, is easily prepared, and rapidly oxidizes thiols to the corresponding disulfides. The reactions proceed cleanly and stop at the disulfide stage without over-oxidation to side-products. The simple procedure and work-up, short reaction times, and excellent yields are all advantages of this reagent.
Amild and stable new chromium(VI) reagent from tributylamine is described. Orange crystalline tributylammonium chlorochromate(VI), (C4H9)3NHCrO3Cl, (TriBACC), is easily prepared in a nearly ...quantitative yield by the interaction of tributylamine with CrO3 and hydrochloric acid in a 1:2:2 mole ratio. This reagent is a versatile reagent for the effective and selective oxidation of organic substrates, in particular for alcohols, under mild conditions.
Opisan je nov blag i stabilan reagens dobijen od hroma(VI) i tributilamina. Medjusobnim dejstvom tributilamina, CrO3 i hlorovodonicne kiseline u molskom odnosu 1:2:2 lako se dobija oranz kristalinican tributilamonijum-hlorohromat(VI), (C4H9)3NHCrO3Cl, (TriBACC), u skoro kvantitativnom prinosu. Proizvod je mnogostrani reagens za efikasnu i selektivnu oksidaciju organskih supstrata, narocito alkohola, u blagim uslovima.
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