Transition metal dithiocarbamate complexes, [M(S2CN(C2H5)(CH2CH2OH)] (M=Co, Ni, Cu, Zn and Cd) have been prepared and characterized by elemental analysis and infrared spectra. Thermal decomposition
of all the complexes occurs in two or three stages. The first stage in all the complexes is always fast with 65-70% mass loss.
In all cases the end product is metal oxide except in the case of cobalt complex which gives Co metal as an end product. During
decomposition of copper complex, first CuS is formed at ~300C which is converted into CuSO4 and finally CuO is formed. However, decomposition in helium atmosphere yields CuS. SEM studies of transition metal dithiocarbamates
reveal needle shape crystalline phase at room temperature and formation of metal sulphide/oxide at higher temperatures. The
activation energy varies in a large range of 33.8-188.3 kJ mol-1, being minimum for the Cu complex and maximum for the Zn complex possibly due to d10 configuration. In the case of Ni, Zn and Cd complexes the order of reaction is two suggesting bimolecular process involving
intermolecular rearrangement. However, in other cases it is a unimolecular process. Large negative values of ΔS# for all the complexes suggest that the decomposition process involves rearrangement.
Authors:Robert Zakrzewski, Żaneta Rembisz, Witold Ciesielski and Grzegorz Celichowski
A chromatographic method for the determination of metal dithiocarbamates: antimonic(III) dipentyldithiocarbamate (Sb-5-DTC), zinc dipentyldithiocarbamate (Zn-5-DTC), zinc dibutyldithiocarbamate (Zn-4-DTC), ferric(III) dipentyldithiocarbamate (Fe-5-DTC), and lead(II) dipentyldithiocarbamate (Pb-5-DTC) was developed. Separations were performed on thin-layer chromatography (TLC) RP-18 silica gel with a propan-2-ol and water mixture (10:1, v/v) as the mobile phase. The chromatographed compounds were detected using the iodine-azide detection procedure. Plates were sprayed with a mixture of sodium azide (2%), potassium iodide (0.01 mol L−1), and starch solution (1%) adjusted to pH 6.0 and exposed to iodine vapor for 15 s. The compounds were visible as white spots against a violet background which were converted into chromatograms using TLSee software. The linear functions of concentration for Sb-5-DTC, Zn-5-DTC, Zn-4-DTC, Fe-5-DTC, and Pb-5-DTC were in the ranges of 100–2000, 50–1000, 50–1000, 50–1000, and 100–3000 pmol per spot, respectively. The limits of detection and quantification were at a level of tens of pmol per spot.
At pH 2, Au, Pd, Pt, U and W form stable pyrrolidine-carbodithioate (PCDT) complexes which can be quantitatively retained by C18-bonded silica gel. Simultaneous determination of the adsorbed metal complexes can be achieved by instrumental neutron activation analysis (INAA). This method allows the determination of Au, Pd, U, and W in natural waters at ng/l levels. For Pt and W, the adsopriton method has an advantage over the solvent extraction technique which generally results in a partial recovery of the PCDT complexes.
The research in thermal analysis and calorimetry, conducted by the author over the period 1964 to 1993, is summarised and
concisely reviewed. The major investigations have focussed on thermal analysis studies of coordination compounds, particularly
the metal dithiocarbamate complexes. A significant solution calorimetric study of some metal dithiocarbamate complexes has
also been undertaken. DSC has been applied to determine the sublimation enthalpies of many metal dithiocarbamate and metal
pentane-2,4-dionate complexes and solution calorimetry has been applied to study the thermochemistry of the latter group of
complexes. Thermal analysis investigations of several inorganic molten salt systems have been initiated. Thermometric titrimetry
has been applied to study metal-macrocyclic ligand systems in aqueous media and particularly those systems of environmental
significance. Temperature calibration standards for TMA have been proposed and TMA has been applied to study the mechanical
properties of several common inorganic compounds. DTA has been applied to study a wide variety of phenols and has subsequently
been applied as an analytical technique to determine the components of solid state phenol mixtures. Thermometric titrimetry
has been applied to determine the phenolic content of wines. A comprehensive thermal analysis study of Australian brown coal
has been undertaken, involving the DSC determination of coal specific energy, a TG/DTA study of the coal pyrolysis and combustion
processes and a TG/DTA and EGA study of the cation catalytic effect on the coal pyrolysis process. Thermal analysis and calorimetric
techniques have been extensively publicised and promoted by the publication of specialist reviews, the presentation of symposia
review papers and the oral presentation of short courses, particularly in the SE Asian region. This review essentially reveals
the diversity of possible application of thermal analysis and calorimetric techniques and the primary significance of thermodynamic
data in the fundamental rationalisation of chemical phenomena.
Authors:A. V. Markin, V. A. Ruchenin, N. N. Smirnova, G. V. Markin, S. Yu. Ketkov, V. A. Kuropatov, V. K. Cherkasov, G. A. Abakumov and G. A. Domrachev
approach to the synthesis of Fullerene-Metaldithiocarbamate complexes, (MII(R2dtc)2)x L C60 (M = Zn, Cd, Hg, Fe, and Mn; x = 1 and 2). The study of magnetic properties and photoconductivity . Cryst Growth Des 8 : 1161 – 1172 10.1021/cg0702481
Authors:Shashi B. Kalia, Geetanjli Kaushal, Rojila and Dharvinder Kumar
Number of studies as well as reports on antifungal [ 1 , 2 ], antibacterial [ 3 – 7 ], anti-alkylation [ 8 , 9 ], anticancer and apoptosis inducing activities [ 10 ] of the mixed-ligand metaldithiocarbamates