Preparation and characterization of tetrachlorocobaltates(II) of α,ω-alkylenediammonium. Magnetic and thermal properties. Crystal structure of [NH3(CH2)5NH3]CoCl4

1999 ◽  
Vol 55 (6) ◽  
pp. 947-952 ◽  
Author(s):  
J. J. Criado ◽  
A. Jiménez-Sánchez ◽  
F. H. Cano ◽  
R. Sáez-Puche ◽  
E. Rodríguez-Fernández
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Thermal Analysis ◽  
Magnetic Susceptibility ◽  
Ground State ◽  
Monoclinic Space Group ◽  
Visible Spectroscopy ◽  
Scanning Calorimetry ◽  
Ft Ir

Tetrachlorocobaltates(II) of diprotonated α,ω-diaminoalkanes with the formula [NH3(CH2) n NH3]CoCl4, where n = 5 (cadaverine; 1,5-pentanediammonium tetrachlorocobaltate), 8 (1,8-octanediammonium tetrachlorocobaltate) and 10 (1,10-decanediammonium tetrachlorocobaltate), were prepared. The compounds were studied by mass spectrometry, FT-IR and visible spectroscopy, magnetic susceptibility techniques and thermal analysis. The compounds contain the tetrahedral tetrachlorocobaltate(II) ion and the corresponding diprotonated diamine (cadaverine, 1,8-octamethylenediamine and 1,10-decamethylenediamine). The compound corresponding to cadaverine crystallizes in the monoclinic space group P21/c, with lattice parameters a = 7.1633 (7), b = 15.940 (3), c = 11.137 (2) Å, β = 98.44 (1)° and Z = 4. Its crystal structure contains slightly distorted tetrahedral CoCl_4^{2-} ions: the largest difference in Co—Cl bond lengths is 0.029 Å and the largest difference in Cl—Co—Cl angles is 7.76°. The compound also contains diprotonated cadaverine ions. An extensive hydrogen-bonding network connects these ions. The slightly positive deviations of the magnetic susceptibility from the Curie–Weiss law are in agreement with the 4 A 2 ground state for the tetrachlorocobaltate anion. The compounds with eight and ten C atoms show phase transitions in the solid state and a greater complexity is observed in their differential scanning calorimetry curves. Unfortunately, no suitable single crystals of these could be obtained.

Synthesis and Characterization of Triethanolamine Borate

2013 ◽  
Vol 709 ◽  
pp. 28-31
Author(s):  
Cheng Xue Wang ◽  
Tian Tian Liang ◽  
Chun Qiao Wei
Keyword(s):  
Mass Spectrometry ◽  
Differential Scanning Calorimetry ◽  
Synthesis And Characterization ◽  
Spectroscopy Analysis ◽  
Scanning Calorimetry ◽  
Reaction Conditions ◽  
Different Types ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Starting with boric acid and triethanolamine , the effect of the different types of the water-carrying agent on the yield was invested, and influences of dosage of water-carrying agent ,the mole ratio of reactants, reaction time on yield were discussed, the optimized reaction conditions were confirmed. The structure of the product was described by Fourier transform-infrared (FT-IR) spectroscopy, NMR Spectroscopy analysis, mass spectrometry (MS) and thermodynamic properties was analyzed by differential scanning calorimetry (DSC) and thermogravimetry (TG).

Structural and IR-spectroscopic characterization of pyridinium acesulfamate, a monoclinic twin

2018 ◽  
Vol 73 (11) ◽  
pp. 753-758
Author(s):  
Enrique J. Baran ◽  
Oscar E. Piro ◽  
Gustavo A. Echeverría ◽  
Beatriz S. Parajón-Costa
Keyword(s):  
Crystal Structure ◽  
Spectroscopic Characterization ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pyridinium Cation ◽  
Ft Ir ◽  
The Fourier Transform ◽  
Ir Spectroscopic

AbstractThe crystal structure of pyridinium 6-methyl-1,2,3,-oxathiazine-4(3H)-one-2,2-dioxide [(C5NH6)(C4H4NO4S)], for short, pyH(ace), was determined by X-ray diffraction methods. It crystallizes as a twin in the monoclinic space group P21/c with a=6.9878(9), b=7.2211(7), c=21.740(2) Å, β=91.67(1)° and Z=4 molecules per unit cell. The structure was determined employing 1599 reflections with I>2σ(I) from one of the twin domains and refined employing 2092 reflections from both crystal domains to an agreement R1 factor of 0.0466. Besides electrostatic attractions, intermolecular pyH···O=C(ace) hydrogen bonds stabilize the acesulfamate anion and the pyridinium cation into planar discrete units parallel to the (100) crystal plane. The units form stacks of alternating ace− and pyH+ ions along the a axis that favors inter-ring π–π interactions. The Fourier transform-infrared (FT-IR) spectrum of the compound was recorded and is briefly discussed. Some comparisons with related pyridinium saccharinate salts are also made.

scholarly journals Synthesis and Characterization of some Mixed Ligand Complexes Containing (8-hydroxyquinoline) and (2 - picoline) with some Metal Ions

2013 ◽  
Vol 10 (2) ◽  
pp. 396-404
Author(s):  
Baghdad Science Journal
Keyword(s):  
Magnetic Susceptibility ◽  
Metal Ions ◽  
Molar Conductivity ◽  
Mixed Ligand ◽  
Synthesis And Characterization ◽  
Conductivity Measurements ◽  
Visible Spectroscopy ◽  
Ft Ir ◽  
Uv Visible

Complexes of some metal ions ( Mn(I? ) , Co(??) , Ni(??) ,Cu (??) , Zn(I?) , Cd (??) , and Hg(??) ) with 8-hydroxyquinoline (Oxine) and 2- Picoline (2-pic ) have been synthesized and characterized on the basis of their FT-IR. and Uv-visible spectroscopy ,atomic absorption molar conductivity measurements and magnetic susceptibility ,from the results obtained the following general formula has been given for prepared complexes [M (oxine)2 (2-pic)2]where M = M(??) = Mn , Co , Ni , Cu , Zn , Cd , Hg(oxine)- = ionic ligand 8-hydroxyquinolin (oxinato)(2- pic) = 2- picoline

Thermal Behaviour of Candesartan Active substance and in pharmaceutical compounds

2017 ◽  
Vol 68 (8) ◽  
pp. 1895-1902
Author(s):  
Ioana Cristina Tita ◽  
Eleonora Marian ◽  
Bogdan Tita ◽  
Claudia Crina Toma ◽  
Laura Vicas
Keyword(s):  
Thermal Behaviour ◽  
Active Substance ◽  
Pharmaceutical Research ◽  
Pharmaceutical Product ◽  
Nitrogen Atmosphere ◽  
Pure Substance ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir

Thermal analysis is one of the most frequently used instrumental techniques in the pharmaceutical research, for the thermal characterization of different materials from solids to semi-solids, which are of pharmaceutical relevance. In this paper, simultaneous thermogravimetry/derivative thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC) were used for characterization of the thermal behaviour of candesartan cilexetil � active substance (C-AS) under dynamic nitrogen atmosphere and nonisothermal conditions, in comparison with pharmaceutical product containing the corresponding active substance. It was observed that the commercial samples showed a different thermal profile than the standard sample, caused by the presence of excipients in the pharmaceutical product and to possible interaction of these with the active substance. The Fourier transformed infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRPD) were used as complementary techniques adequately implement and assist in interpretation of the thermal results. The main conclusion of this comparative study was that the TG/DTG and DSC curves, together with the FT-IR spectra, respectively X-ray difractograms constitute believe data for the discrimination between the pure substance and pharmaceutical forms.

High-pressure Syntheses and Characterization of the Rare-earth Fluoride Borates RE2(BO3)F3 (RE=Tb, Dy, Ho)

2013 ◽  
Vol 68 (11) ◽  
pp. 1198-1206 ◽  
Author(s):  
Ernst Hinteregger ◽  
Michael Enders ◽  
Almut Pitscheider ◽  
Klaus Wurst ◽  
Gunter Heymann ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Rare Earth ◽  
Monoclinic Space Group ◽  
Rare Earth Fluoride ◽  
Earth Fluoride ◽  
Structure Determinations ◽  
New Compounds ◽  
Rare Earth Fluorides

The new rare-earth fluoride borates RE2(BO3)F3 (RE=Tb, Dy, Ho) were synthesized under highpressure/ high-temperature conditions of 1:5 GPa=1200 °C for Tb2(BO3)F3 and 3:0 GPa=900 °C for Dy2(BO3)F3 and Ho2(BO3)F3 in a Walker-type multianvil apparatus from the corresponding rareearth sesquioxides, rare-earth fluorides, and boron oxide. The single-crystal structure determinations revealed that the new compounds are isotypic to the known rare-earth fluoride borate Gd2(BO3)F3. The new rare-earth fluoride borates crystallize in the monoclinic space group P21/c (Z = 8) with the lattice parameters a=16:296(3), b=6:197(2), c=8:338(2) Å , b =93:58(3)° for Tb2(BO3)F3, a= 16:225(3), b = 6:160(2), c = 8:307(2) Å , b = 93:64(3)° for Dy2(BO3)F3, and a = 16:189(3), b = 6:124(2), c = 8:282(2) Å , β= 93:69(3)° for Ho2(BO3)F3. The four crystallographically different rare-earth cations (CN=9) are surrounded by oxygen and fluoride anions. All boron atoms form isolated trigonal-planar [BO3]3- groups. The six crystallographically different fluoride anions are in a nearly planar coordination by three rare-earth cations.

scholarly journals Stability evaluation of tocopheryl acetate and ascorbyl tetraisopalmitate in isolation and incorporated in cosmetic formulations using thermal analysis

2010 ◽  
Vol 46 (1) ◽  
pp. 129-134 ◽  
Author(s):  
Mariana Mandelli de Almeida ◽  
Cibele Rosana Ribeiro de Castro Lima ◽  
Joyce Santos Quenca-Guillen ◽  
Elder Moscardini Filho ◽  
Lucildes Pita Mercuri ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Raw Materials ◽  
Skin Aging ◽  
Tocopheryl Acetate ◽  
Stability Evaluation ◽  
Scanning Calorimetry ◽  
Cosmetic Formulations ◽  
Cosmetic Formulation ◽  
Excellent Tool

In view of the increase in the number of cosmetic preparations containing antioxidant vitamins, chiefly, due to their action in preventing the process of skin aging, there is a need to develop pre-formulation studies and to validate analytical methods in order to obtain high quality products. Thus, the objective of this research was to evaluate and compare the thermal behavior of tocopheryl acetate and ascorbyl tetraisopalmitate as raw materials, and incorporated into a base cream. Thermogravimetry (TG / DTG) and differential scanning calorimetry (DSC) were used for this purpose. Both vitamins were found to be stable up to 250ºC. The base cream (placebo) and the sample (base cream containing the vitamins) presented different weight loss. Thermal analysis has shown itself to be an excellent tool for the characterization of these vitamins and can be used in routine analysis for quality control of this type of cosmetic formulation.

scholarly journals ISOLATION OF 2-CHLOROBENZIMIDAZOLE FROM MELIA DUBIA LEAF EXTRACT AND ITS STRUCTURAL CHARACTERISATION

2017 ◽  
Vol 9 (10) ◽  
pp. 67 ◽  
Author(s):  
G. Dayana Jeyaleela ◽  
S. Irudaya Monisha ◽  
J. Rosaline Vimala ◽  
A. Anitha Immaculate
Keyword(s):  
Mass Spectrometry ◽  
1H Nmr ◽  
Research Work ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
Ft Ir ◽  
Uv Visible ◽  
Isolated Compound ◽  
Promising Source

Objective: Natural products from medicinal plants, either as isolated compounds or as standardized plant extracts exhibit promising source of medicinal activity against various diseases. The aim of the present work was to make an attempt of isolation of bioactive principle and characterization of the isolated compound, from the medicinal plant Melia dubaiMethods: The extraction was done by a cold percolation method and the compound was separated and isolated by chromatography technique such as a thin layer chromatography (TLC), column chromatography and high-performance liquid chromatography (HPLC). The isolated compound was crystallized and the structural characterization of the isolated compound was made using UV-Visible, FT-IR, 1H-NMR, GC-MS and MS techniques which confirmed the structure of the isolated compound.Results: The separated and isolated compound was characterized by both physical and spectral methods like Ultraviolet-Visible spectroscopy (UV-Visible), Fourier transform infrared spectroscopy (FT-IR), Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), Gas chromatography-mass spectrometry (GC-MS), and Mass spectrometry(MS). Based on the studies, organizational characteristics of one bioactive principle were deciphered. The results revealed that the isolated species is 2-chlorobenzimidazole and it agreed well with the reported value and spectra for 2-chlorobenzimidazole.Conclusion: The above results obtained in this research work clearly indicated the promising occurrence of 2-chlorobenzimidazole in Media dubia plant leaves. The future scope of these studies may guide us to view the biological activity of the isolated compound.

scholarly journals Synthesis, Mesomorphism and the Optical Properties of Alkyl-deuterated Nematogenic 4-[(2,6-difluorophenyl)ethynyl]biphenyls

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4653
Author(s):  
Jakub Herman ◽  
Piotr Harmata ◽  
Michał Czerwiński ◽  
Olga Strzeżysz ◽  
Marta Pytlarczyk ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Mass Spectrometry ◽  
Differential Scanning Calorimetry ◽  
Optical Properties ◽  
Liquid Crystalline ◽  
Near Infrared ◽  
Synthesis And Characterization ◽  
Molecular Approach ◽  
Scanning Calorimetry

The synthesis and characterization of new deuterated liquid crystal (LC) compounds based on phenyl tolane core is described in this paper. The work presents an alternative molecular approach to the conventional LC design. Correlations between molecular structure and mesomorphic and optical properties for compounds which are alkyl-hydrogen terminated and alkyl-deuterium, have been drawn. The compounds are characterized by mass spectrometry (electron ionization) analysis and infrared spectroscopy. They show enantiotropic nematic behavior in a broad temperature range, confirmed by a polarizing thermomicroscopy and differential scanning calorimetry. Detailed synthetic procedures are attached. Synthesized compounds show a significantly reduced absorption in the near-infrared (NIR) and medium-wavelength infrared (MWIR) radiation range, and stand as promising components of medium to highly birefringent liquid crystalline mixtures.

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