have chlorine bridged distorted-octahedral geometry. It has been observed that the dithiocarbamato moiety is symmetrically bonded in all the cases. A three stage TGA profile is observed for all the complexes leading to the formation of respective metal sulfide as the end-product. The molar conductance of 10 -3 mol L -1 solution of the complexes measured in DMSO is indicative of their non-ionic nature. Keywords: dithiocarbamates, transition metals, thermal analysis, symmetrical bonding IntroductionDithiocarbamates are used to stabilize a wide range of oxidation states of different metal ions. 1 A large number of compounds are known where CS 2 binds in η 1 -end on, η 2 -side or in η 3 -coordination modes. 2-4 The major advantage of using the small bite-angle of dithiocarbamato moiety as a stabilizing chelating ligand, is its unique property to remain intact under a variety of reaction conditions. 5 Nowadays copper(II) dithiocarbamate is successfully used as single source precursor for the growth of semiconducting copper sulfide thin films. 6 The iron(II), iron(III) dithiocarbamates have been studied for their spincrossover phenomenon, 7 radical traps for NO, 8 and as antioxidants and pro-oxidants in biological systems. 9 Diethyl dithiocarbamates are also known to inhibit the activity of Cu/Zn-superoxidedismutase (SOD) through the withdrawal of copper from the protein both in vivo and in vitro. 10 Some dialkyl-substituted dithiocarbamates have proved to be an efficient anti-alkylating, anti-HIV and froth-floatation agents. 11 The optical and electrochemical properties of dithiocarbamates can effectively be used to construct sensors for guest molecules and macromolecules. [12][13][14] In this paper, we report a convenient one-pot synthesis of the transition metal dithiocarbamates via template procedure. In the present work, a condensation reaction was carried out between acetylacetone, ethylenediamine, 108 Siddiqi et al. J. Braz. Chem. Soc. carbon disulfide in a single step leading to the formation of a ring like complex ( Figure 1 and Figure 2). ExperimentalHydrated metal chlorides (BDH) acetylacetone, carbon disulfide (Merck) and ethylenediamine (Ranbaxy) were used as received. Methanol was used after distillation. Elemental analyses (C, H, N and S) were carried out with a Flash EA-1112 Analyser, CE Instrument. IR spectra (4000-400 cm -1 ) were recorded on a FT-IR Perkin-Elmer Spectrum BX as KBr disc while the 600-200 cm -1 range were scanned on CsI on Nexus FT-IR Thermo Nicolet, Madison Wisconsin. The conductivity measurements were carried out with a CM-82T Elico conductivity bridge in DMSO. The electronic spectra were recorded on a Cintra 5GBC spectrophotometer in DMSO. Magnetic susceptibility measurements were done with a Sherwood Scientific MSB Auto at room temperature. TGA/DSC was performed with a Universal V3.8 B TA SDT Q600 Build 51 Thermal Analyzer under nitrogen atmosphere using alumina powder as reference material. The heating rate was maintained at 10 °C min -1 . The metal contents were estimated by...

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