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Synthesis, characterization and thermal behaviour of adducts

8-quinolinol with the photoproduct of octacyano-molybdate (IV) and -tungstate (IV) with ethylenediamine and triethylenetetramine

Journal of Thermal Analysis and Calorimetry
Authors: S. I. Ali and A. M. A. Ansari

The photoproduct of octacyanomolybdate(IV) and -tungstate(IV) with ethylenediamine and triethylenetetramine give complexes of the type K3[Mo(O2)(O)(OH)(C9H7ON)]·3C9H7ON I, K2[W(O2)(O) (C9H7ON)3] II and K3[Mo(CN)3(OH)4(C9H7ON)]·2C9H7ON·3H2O III with 8-quinolinol (oxine). The IR spectra of the complex III shows the presence ofv(CN) peaks in the range 2047–2108 cm−1 and oxine groupv(C-O) in the complex I, II and III in the range of 1100–1150 cm−1. The lower region of IR spectra shows the M=O stretching while the higher thev(N-H) andv(OH). Thermal studies show the removal of uncoordinated water at 131‡C from complex III. The decomposition of complexes I and II start from 150 and 212‡C respectively. Oxine and cyano molecules were removed in stages at higher temperatures. The final product of the thermal decomposition was oxide which was of polymeric nature. The kinetic parameters viz. order of reaction ‘n’ and activation energy ‘E’ were determined by different methods.

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Abstract  

Thermal behaviour of tri(O,O'-diisopropyldithiophosphate)cobalt(III), Co(dptp)3 and bis (O,O'-diethyldithiophosphate)nickel(II), Ni(detp)2 and its adducts with pyridine, Ni(detp)2(py)2 or 4-methylpyridine, Ni(detp)(mpy)2 in a dynamic nitrogen atmosphere was investigated by TG-DTG and DSC techniques, which showed a medium endothermic peak for the evolution process of pyridine(or 4-methylpyridine) and a strong exothermic peak for that of O,O'-diethyldithiophosphate. The thermal stability and decomposition patterns for these compounds were compared and interpreted in terms of structural features such as bond character and steric effects. The kinetic parameters and mechanisms of every decomposition stage involved for all these complexes were obtained employing the non-isothermal kinetic analysis method suggested by Malek et al., which showed the kinetics mechanism for pyrolysis of pyridine(or 4-methylpyridine) is an S-B empirical model with lower activation energy, while that of O,O'-dialkyldithiophosphate is a diffusion model. These results are in accord with the fact that two ligands are of different type.

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this article, it is described a study of the adducts formed by the ligands 2,2′-bipyridine and 2,2′-bipyridine N , N ′-dioxide with cadmium(II) halides to determine several thermochemical parameters, including, the mean strength of the cadmium

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methylamine group, as shown in Fig. 1 . Fig. 1 Molecular structures for a sorbitol and b meglumine The increased applicability of meglumine lies in its ability to form adducts

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Abstract  

The present overview presents a brief survey on the liquid-liquid extraction mechanism of metal chelates and adducts, the different reported reaction models and the most common methods used to follow the kinetics of extraction process are given. The effect of the different phenomena affecting the extraction rate and the importance of the kinetic information in connection with technical processes and counter-current modelling are also discussed.

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Abstract  

Solid complexes of plutonylion with benzoyl (PMBP), acetyl (PMAP) and trifluoroacetyl (PMTFP) derivatives of 1-phenyl-3-methylpyrazol-5-one and various oxo donors such as dihexyl sulfoxide (DHSO), dioctyl sulfoxide (DOSO), dibutyl hexanamide (DBHA), dibutyl octanamide (DBOA) and dibutyl decanamide (DBDA) have been synthesized and characterized. Analytical data establish that sulfoxides form 11 adducts and have the stoichiometry PuO2·X2·Y (X=PMBP, PMAP and PMTFP) and Y=DHSO and DOSO while amides form 12 adducts of the type PuO2X2·2A where A=DBHA, DBOA and DBDA. The I. R. spectra of sulfoxide and amide complexes indicate that the ligands are O-bonded. Spectrophotometric investigations of the benzene solution of these complexes indicate a bathochromic shift of the 831 nm peak to 848–853 nm region, which confirms the retention of PuO 2 2+ moiety in these synergistic adducts.

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Abstract  

Solid adducts SbX3L-pic (X=Cl, I and L=α-, β- and γ-picolines) were synthesized and characterized by elemental analysis, 1H and 13C NMR, IR spectroscopy and thermal analysis. The infrared spectroscopy and the magnetic resonance for 1H and 13C nuclei of these compounds suggest that the ligands coordinate through nitrogen atom. Kinetic studies were accomplished by means of thermogravimetric data, through isothermal and non-isothermal techniques. The best adjusting models for adducts thermal decomposition were R1 for isothermal and R1 and R2 for the non-isothermal methods. The energy of activation values obtained by isothermal method indicate the following orders of thermal stability for adducts: i) SbCl3α-pic>SbCl3β-pic>SbCl3γ-pic and ii) SbI3β-pic>SbI3γ-pic>SbI3α-pic. The activation energy values obtained by non-isothermal were higher than those from isothermal methods, showing the order of stability:iii) SbCl3α-pic<SbCl3β-pic<SbCl3γ-pic and iv) SbI3β-pic>SbI3α-pic=SbI3γ-pic. These obtained data through R1 model presented the kinetic compensation effect for trichloride adducts, which could be associated to both isothermal and non-isothermal processes.

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Abstract  

The temperature dependence of the vapour pressure of californium-249 hexafluoroacetylacetonate adducts with tributylphosphate /TBP/, tributylphosphineoxide /TBPO/ and dipropylsulphoxide /DPSO/ is determined. The enthalpy and entropy sublimation of the compounds are calculated.

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Abstract  

The [InCl3(L)n] (where L is 2,2′-bipyridine (bipy), 2,2′-bipyridine N,N′-dioxide (bipyNO), N,N-dimethylacetamide (dma), urea (u), thiourea (tu) or 1,1,3,3-tetramethylthiourea (tmtu); n = 1.5, 3 or 4) were synthesized and characterized by melting points, elemental analysis, thermal analysis and IR spectroscopy. The enthalpies of dissolution of the adducts, Indium(III) chloride and ligands in 1.2 M aqueous HCl were measured and by using thermochemical cycles, the following thermochemical parameters for the adducts have been determined: the standard enthalpies for the Lewis acid/base reactions (Δr H θ), the standard enthalpies of formation (Δf H θ), the lattice standard enthalpies (ΔM H θ), and the standard enthalpies of decomposition (ΔD H θ).

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