Palladium dithiocarbamates

Considerably less is known about the chemistry of palladium and platinum 1,1-dithio complexes. Of late, there has been only one report that dealt with the synthesis of a large number of palladium dithiocar-bamates 392). Twenty-five yellow palladium dithiocarbamate complexes were obtained by reaction of PdCla with NaR2dtc in methanol solution. Several other reports have appeared in which a few dithiocarbamate complexes of palladium were synthesized. Thus, the novel [Pd (OH)2dtc 2], which is soluble in water, was isolated 393). The synthesis of optically active palladium(II) complexes of AT-alkyl-a-phen-ethyldithiocarbamates, similar to (XXIV), via the reaction between the optically active amine, CS2, and PdCl2, has been described. From ORD and CD spectra, it has been established that the vicinal contribution of a remote, asymmetric carbon center could give rise to optical activity of the d—d transitions of palladium 394). Carbon disulfide has been shown to insert into the Pt-F bond of [PtF(PPh3)3]HF2, and X-ray studies indicated the structure (XXIX). 

The alleged preparation of the supposed cobalt(II) complex Na[Co(Et2dtc)3] described by D Ascenzo and Wendlandt (305) has been repeated by Holah and Murphy (306), who identified the product as [Co(Et2dtc)3]. Complexes of cobalt(III), nickel(II), and palladium(II) salts with cationic, dithiocarbamate ligands have been synthesized (307). Reaction of the secondary amine (Et2N(CH2)2)2NH with CS2 produces... 

Pt(S2CNMe(Hex))2] and [Pd(S2CNMe(Hex))2] have been synthesized and used as precursors to grow the first TOPO-capped PtS and PdS nanoparticles and thin films of PtS and PdS by the metallo-organic chemical vapor deposition (MOCVD) method [204]. Platinum and palladium chalcogenides find applications in catalysis [205-210] and materials science [211,212]. The synthesis of thiocarbamato complexes of platinum and palladium from reaction of an aqueous solution of ammonium dithiocarbamate with the platinum or palladium salt has been reported by Nakamoto et al. [213]. However... 

Cleave the Aloe groups (see Notes 6, 7) Add the resin to 1 g (PPh3)4Pd in 10 mL chloroform acetic aciddV-methyl morpholine (37 2 1, v/v/v) and shake for 5 h. Wash the resin 2x with 25 mL 0.5% diisopropyl ethyl amine in DMF, 2x with 25 mL of 0.5% sodium diethyl dithiocarbamate in DMF, and 2x with 25 mL DMF alone. Special reagents needed tetrakis triphenylphosphine palladium diethyl dithiocarbamate. 

Y. S. Chung, R. M. Barnes, Determination of gold, patinum, palladium and silver in geological samples by inductively coupled plasma atomic emission spectrometry after poly(dithiocarbamate) resin pre-treatment,. /. Anal. Atom. Spectrom., 3 (1988), 1079D 1082. 

Some extremely low detection limits in chemical samples have been reported by APDC/MIBK and other dithiocarbamate extractions. Further increased concentration factors can be obtained by back-extraction into a minimum of acid. Copper in ammonium fluoride solution used in semiconductor processing has been determined down to 4.5 X 10 7% [20]. To a 40% ammonium fluoride solution (50 ml) was added ammonia solution (1ml), 50—60 /Ltg of a palladium(II) carrier solution (dissolved in 1ml) and sodium diethyldithiocarbamate (5 ml). After extraction of the copper chelate into chloroform the solvent was evaporated, the residue dissolved in concentrated nitric acid (10 drops) and water (2 ml) and this was then evaporated. The final dissolution was in concentrated hydrochloric acid (2 drops) and concentrated nitric acid (ldrop). The solution was made up to 1 ml and the determination made by standard additions using an air/ acetylene flame and the 324.7 nm copper resonance line. 

Carbon-based sorbents are relatively new materials for the analysis of noble metal samples of different origin [78-84]. The separation and enrichment of palladium from water, fly ash, and road dust samples on oxidized carbon nanotubes (preconcentration factor of 165) [83] palladium from road dust samples on dithiocarbamate-coated fullerene Cso (sorption efficiency of 99.2 %) [78], and rhodium on multiwalled carbon nanotubes modified with polyacrylonitrile (preconcentration factor of 120) [80] are examples of the application of various carbon-based sorbents for extraction of noble metals from environmental samples. Sorption of Au(III) and Pd(ll) on hybrid material of multiwalled carbon nanotubes grafted with polypropylene amine dendrimers prior to their determination in food and environmental samples has recently been described [84]. Recent application of ion-imprinted polymers using various chelate complexes for SPE of noble metals such as Pt [85] and Pd [86] from environmental samples can be mentioned. Hydrophobic noble metal complexes undergo separation by extraction under cloud point extraction systems, for example, extraction of Pt, Pd, and Au with N, A-dihexyl-A -benzylthiourea-Triton X-114 from sea water and dust samples [87]. 

Lesnlewska, B.A., Godlewska, I., Godlewska-Zylklewlcz, B. The study of applicability of dithiocarbamate-coated fullerene C60 for preconcentration of palladium for graphite furnace atomic absorption spectrometric determination in environmental samples. Spectrochim. Acta B 60, 377-384 (2005)... 

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