Dithiocarbamate complexes applications

Extended linear chain inorganic compounds have special chemical and physical properties [60,61], This has led to new developments in fields such as supramolecular chemistry, acid-base chemistry, luminescent materials, and various optoelectronic applications. Among recent examples are the developments of a vapochromic light emitting diode from linear chain Pt(II)/Pd(II) complexes [62], a luminescent switch consisting of an Au(I) dithiocarbamate complex that possesses a luminescent linear... 

The analysis of environmentally-relevant samples is a major field of application. Based on the work of Garbarino and Taylor [421], a method has been proposed by the US EPA (Environmental Protection Agency) [422] and later by DIN [423] for waste water analysis. The latter, standardized procedure describes the sample decomposition, the analytical range for 22 elements and frequent interferences of ICP-AES in waste water analysis. For the analysis of natural waters, hydride generation [424], preconcentration based on liquid-liquid extraction of the dithiocarbamate complexes [425], adsorption of trace elements onto activated carbon [426] and also co-precipitation [e.g. with In(OH)2] [427], etc. have been reported and special emphasis has been given to speciation (as given in the Refs, in [428]) and on-line preconcentration [134]. 

Closely related are the 1-benzylamino-l-deoxylactitol dithiocarbamate salts developed by Eybl and co-workers316 317 for the same purpose. However, the most important application of 175 is, probably, its use as a nontoxic, water-soluble nitric oxide probe in vivo. In view of the central importance that this gaseous free-radical species plays in regulating a broad range of important biological functions, its detection and quantification near its site of production and action is of prime importance. For this purpose, the ferrous salt of MGD, which forms a stable water-soluble mononitrosyl iron-dithiocarbamate complex (176) with a characteristic electron spin resonance (ESR) spectrum at room temperature, is currently used.318-323... 

In this analysis of the nmr data we have that the results for a variety of solvents and over a wide temperature range may be interpreted as arising from small changes in the crystal field environment of the iron atom due to two solvent interactions - a term which is an intrinsic property of the solvent and a second term arising from a solute-solvent interaction. Although the application of the model has been simplified the results nevertheless give an insight into the effect of the solvent on the nmr shifts of these iron dithiocarbamate complexes. 

Although nonhomoleptic complexes of Sn have been extensively studied because of their considerable structural diversity and potential applications, for example, in chemotherapy, those of lead are rare. The complex [Pb(phen)(S2C-NEt2)2] (phen = 1,10-phenanthroline) is one of only a few examples of a nonhomoleptic lead(II) dithiocarbamate complex (108). The geometry at Pb (Fig. 7) is best considered as distorted trigonal bipyramidal, with the bridging S atoms occupying axial positions. 

This chapter is aimed at inorganic chemists and as such it focuses on the synthesis, properties, and reactivity of transition metal dithiocarbamate complexes. A flavor of the established and potential applications of each metal type is given in Section IV, but space restrictions nessetate that their applications in analytical chemistry and the agricultural industry (27), together with their widespread biological applications (45—48) are not fully developed. 

The thermochemistry of dithiocarbamate complexes is of considerable interest, primarily since they can be used as molecular precursors for the synthesis of a range of technologically important metal sulfides, especially those of copper and zinc (see Sections III.H.l.g.ii and III.I.Lh.i). The successful application of this approach relies on the volatility of the metal complexes and the strength of the metal-sulfur and metal-carbon bonds since the latter must be cleaved, while the former is retained (at least to some extent). Consequently, a large number of studies have focused on the thermochemical properties of transition metal dithiocarbamate complexes and HiU and co-workers (22, 562, 563) and others (23, 564) reviewed aspects of these. 

Prior to 1980, dithiocarbamate complexes of technetium were unknown. However, over the past 20 years considerable developments have been made, driven mainly by the application of technetium(V) nitride complexes in radiopharmaceuticals. More recently, dithiocarbamate chemistry of technetimn has been more fully explored with diphosphine, carbonyl, oxo, imido, and other ligand combinations. 

Dithiocarbamates stabilize copper in the +1, +2, and +3 oxidation states, with copper(II) bis(dithiocarbamate) complexes, first reported by Delepine (2) being most common. Later, Cambi and Coriselli (1662) detailed the synthesis of a range of these and also copper(I) dithiocarbamate complexes, and in the 1960s copper(III) complexes were prepared (1663). Over the past 20 years, some significant new developments have been made and a wide range of applications has been established. 

Hi. Biological Applications. Copper(II) bis(dithiocarbamate) complexes have a number of potential biological applications. For example, while dithio-carbamate salts (R = Me, Ft) are potent inhibitors of a clonogenic response in human C34 bone marrow cells, addition of copper sulfate greatly potentiates the hematotoxicity, suggesting a more general role for copper in dithiocarba-mate-induced hematotoxicity (1779). 

V. Other Applications. Bis(dithiocarbamate) complexes show a number of other potential applications. Some (R =Et R2 = C4Hg, C5H10) have been used as photostabilizers in the photodegradation of poly(vinylchloride) (PVC). The initial photoproduct is believed to be [Cu(S2CNR2)] , which is then rapidly oxidized by the carbon-chlorine bonds to produce [CuCl(S2CNR2)]2 and a cross-linked polymer (1790,1791). 

The dithiocarbamate chemistry of the group 12 (11B) elements is well developed, with applications in the areas of analytical chemistry, agriculture, rubber vulcanization, and as molecular precursors to metal sulfides. As expected, their chemistry is constrained to the - -2 oxidation state and it is the bis(dithiocarbamate) complexes [M(S2CNR2)2], which are the most common, being first prepared in 1907 (2). 

V. Other Applications. In other potential applications, zinc bis(diamyl-dithiocarbamate) has been shown to be a better antioxidant for motor oils than zinc dithiophosphates (2047), and other bis(dithiocarbamate) complexes have been shown to have liquid-crystal properties (1485). 

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