Dimeric structures dithiocarbamates

Af,Af -dimethyl-Af,lV -bis(2 -mercaptoethyl-l,2-ethylenediamine, 1351 di-(i-sulfido preparation, 1252 di-(i-sulfidocysteinato dimers, 1247 dithiocarbamates, 1354 dithiolenes, 1354 electronic spectra, 1353 ESR, 1352 fluorides, 1347 halide oxo monomeric, 1348 crystal structures, 1348 halides, 1347,1353 imido,1353... 

Figure 7. The ORTEP plot showing the dimeric structure of [Pb(phen)(S2CNEt2)]. The N substituents of the dithiocarbamates and atom labels of the phen Ugands have been omitted for clarity.

Various bidentate ligands like dithiocarbamate afford monomeric square planar complexes specific examples are Pt(S2CNEt2)2 and Pt(Se2CNBu)2 (confirmed by X-ray). A similar structure is found for the dithiobenzoate Pd(S2CPh)2 one form of the dithioacetate is dimeric, a second form is a mixture of monomers and dimers. 

The utility of thallium(III) salts as oxidants for nonaromatic unsaturated systems is a consequence of the thermal and solvolytic instability of mono-alkylthallium(III) compounds, which in turn is apparently dependent on two major factors, namely, the nature of the associated anion and the structure of the alkyl group. Compounds in which the anion is a good bidentate ligand are moderately stable, for example, alkylthallium dicar-boxylates 74, 75) or bis dithiocarbamates (76). Alkylthallium dihalides, on the other hand, are extremely unstable and generally decompose instantly. Methylthallium diacetate, for example, can readily be prepared by the exchange reaction shown in Eq. (11) it is reasonably stable in the solid state, but decomposes slowly in solution and rapidly on being heated [Eq. (23)]. Treatment with chloride ion results in the immediate formation of methyl chloride and thallium(I) chloride [Eq. (24)] (55). These facts can be accommodated on the basis that the dicarboxylates are dimeric while the... 

The in vivo antitumor and trypanocidal effects of dimeric [Irn2(CH3COO)4(L)ra]° (L = classical organic antimalarial drugs, n= 1, 2) are reported.494 The dimeric complexes are characterized by IR spectroscopy. Further studies of monomeric Ir11 complexes, IrnL2, where L = alkyl or aryl dithiocarbamates and xanthates, reveal no clear relation between antitumor and antitrypanosomal actvities.495 Structure-activity data for the Ir11 complexes is presented. 

Dimeric gold(I) complexes with dithiocarbamate ligands possess a strong propensity to aggregate and form chains with short intermolecular Au Au contacts, they have been known for a long time but new structural characterizations have come into light. Thus compounds of the type... 

Zinc carbamate complexes are well known, and the structural types and stabilities can be compared with thiocarbamates and dithiocarbamates which are discussed in Sections 6.8.11.1.3 and 6.8.7.1.4482 Carbamates of zinc can be formed from the reaction of carbon dioxide with alkylzinc alkyl amides and further reaction with alkylzinc can give a distorted cubane structure.483 The tetrameric diethylcarbamate species initially formed can also be used to produce monomeric or dimeric carbamate structures in reaction with amines tetramethylethylenediamine forms a monomer [(Me2NCH2)2Zn(02CN(C2H5)2)2] with an octahedral zinc center and pyridine forms a dimer[CsH5NZn2Me(02CN(C2H5)2)3] with tetrahedral zinc centers.484... 

The structural chemistry of some metal dithiocarbamates, i.e. systematics, coordination modes, crystal packing, and supramolecular self-assembly patterns of nickel, zinc, cadmium, mercury,363 organotin,364 and tellurium,365 366 complexes has been thoroughly analyzed and discussed in detail. Supramolecular self-assembly frequently occurs in non-transition heavier soft metal dithiocarbamates. Thus, lead(II),367 bismuth(III)368 zinc,369 cadmium,370 and (organo)mercury371 dithiocarbamates are associated through M- S secondary bonds, to form either dimeric supermolecules or chain-like supramolecular arrays. The arsenic(III)372 and antimony(III)373 dithiocarbamates are... 

By analogy to the zinc structure, the coordination sphere around the silver(II) ion was anticipated to contain four sulfur atoms from two dialkyl dithiocarbamates in a square planar arrangement. Dimerization would occur by interaction via two Ag—S bridges (8S).538... 

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