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A new series of manganese(III), cobalt(II), nickel(II), zinc(II), cadmium(II) and mercury(II) complexes with monomethylsubstituted dithiocarbamates as ligands has been synthesized and studied. Their structures are discussed in relation to their spectroscopic, magnetic and thermal properties. The dithio-ligands exhibit bidentate behaviour acting as S,S′donors in all the complexes. In the far i.r. region particular attention is paid to a comparison of the spectra of the octahedral complexes with those of the other metal derivatives (1∶2 metal to ligand molar ratio). The e.s.r. spectra are indicative of aD2h symmetry in the cobalt(II) complexes.

The following complexes of 2-amino-5-methyl-1,3,4-thiadiazole (L) have been prepared and studied: CoL 2 X 2 (X = Cl, Br, I, OAc), pseudotetrahedral with C 2v symmetry; ML 4 (NO 3 ) 2 (M = Co, Ni), octahedral with uncoordinated NO − 3 ionic groups; NiLCl 2 , NiL 1.5 Br 2 ·0.025EtOH, NiL 2 I 2 ·0.75EtOH, with octahedral polymeric structures; Cu 4 L 5 Cl 8 , Cu 3 L 4 Br 6 , CuL 4 Br 2 and Cu 2 L 3 (OAc) 4 ; The ligand is coordinated to the metal atom through the aminic nitrogen atom in the CoL 2 X 2 and CuL 4 Br 2 complexes and through the aminic nitrogen together with one or two cyclic nitrogen atoms in the other complexes. Electronic spectra, with their crystal field parameters for cobalt and nickel, infrared and far infrared spectra, magnetic moments and some molar conductivities are reported and discussed.

The cobalt(II) complexes of 2, 5-dimethyl-1, 3, 4-thiadiazole (DTZ) Co(DTZ)2 X2 (X=Cl, Br, I, NO3) have been prepared and investigated. Their observed magnetic moments lie in the range 4.4–4.6 B.M. The complexes have a pseudo-tetrahedral coordination; a threefold splitting of the electronic v 2 and v 3 bands of the halide complexes indicate a C2v symmetry. In the nitrate complex the anion is coordinated as monodentate ligand as shown by its infrared bands; however a weak interaction of a second oxygen atom, with a consequent distortion of the pseudo-tetrahedral coordination toward a six-coordination, cannot be excluded. In all these complexes the ligand DTZ is coordinated to the metal ion through one of the two nitrogen atoms. The far i. r. v(CoN) and v(CoX) (X=Cl, Br, I, O) bands were identified.

The reaction of copper(II) chloride with 1,3-thiazolidine-2-thione in absolute ethanol yields the complex CuL2Cl2. This derivative has been studied by elemental analyses, molar conductance, magnetic moment measurements at different temperatures, electronic and infrared spectroscopy, thermal analyses (TG and DTG) and e.p.r. techniques. The complex has a pseudooctahedral stereochemistry, with bridging halides and with the ligands monodentate-S-bondedvia the exocyclic sulphur atom.

The preparation and magnetic susceptibility, electronic, infrared, electrical conductivity and thermogravimetric studies of a series of monomethylsubstituted piperidine dithiocarbamates of silver(I), gold(I) and gold(III) are reported. The complexes are formulated as AgRdtc, AuRdtc, Au(Rdtc)3. Au(Rdtc)2X and AuRdtcX2 (X=Cl, Br). The dithioligands exhibit both bidentate behaviour acting as S,S ' -donors and monodentate behaviour acting as S-donors, depending on the type of the complex. The diamagnetic behaviour of the gold(III) derivatives is in accord with the usual low-spin d8 configuration. The metal-sulphur and metal-halide stretches have also been assigned and are in accord with the proposed structures. The molecular weight determinations indicate monomeric structures for the Au(Rdtc)3 and AuRdtcX2 complexes and dimeric structures for the Au(Rdtc)2X derivatives. The results of the spectroscopic studies indicate that in the Au(Rdtc)3 complexes one of the dithiocarbamate groups must act as a bi...

We report the preparation and characterization of the complexes of rhodium(III), iridium(III), palladium(II) and platinum(II) with the following ligands: Pzdtc, N-MePzdtc, N-PhPzdtc, Pipdtc, 4- PhPipdtc, Morphdtc, Timdtc, and with their methyl esters. The dithio ligands act as bidentate S , S ′-donors in all the new derivatives. From the electronic absorption spectra the values of the ligand field parameters were determined. The nephelauxetic parameters are indicative of a strong covalency in the metal-ligand bond. All the compounds reported here are diamagnetic.