Template synthesis of symmetrical transition metal dithiocarbamates

Abstract

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...

New heteroleptic palladium(II) dithiocarbamates: synthesis, characterization, packing and anticancer activity against five different cancer cell lines

“…In the spectra of the synthesized Pd(II) complexes only one strong band is observed in the region 989 cm −1 ( 1 ) and 996 cm −1 ( 2 ) which indicates that the dithiocarbamate ligands are bonded in bidentate fashion to Pd(II) centers. A new band with medium intensity at 382 cm −1 ( 1 ) and 386 cm −1 ( 2 ) corresponding to PdS is observed as was reported earlier . The PdCl stretch is observed at 312 cm −1 ( 1 ) and 308 cm −1 ( 2 ) …”

New heteroleptic palladium(II) dithiocarbamates: synthesis, characterization, packing and anticancer activity against five different cancer cell lines

“…In the spectra of the synthesized Pd(II) complexes only one strong band is observed in the region 989 cm −1 ( 1 ) and 996 cm −1 ( 2 ) which indicates that the dithiocarbamate ligands are bonded in bidentate fashion to Pd(II) centers. A new band with medium intensity at 382 cm −1 ( 1 ) and 386 cm −1 ( 2 ) corresponding to PdS is observed as was reported earlier . The PdCl stretch is observed at 312 cm −1 ( 1 ) and 308 cm −1 ( 2 ) …”

Design and Characterization of New Dinuclear Macrocyclic Dithiocarbamate Complexes by the Preparation of a Free Ligand Derived from Isopropylamine

“…The Cu(II) _ complex gives two (d-d ) absorption bands at 769 nm and at an average of 791nm, 839 nm, corresponding to 2 B 1 g → 2 B 2 g and 2 B 1 g → 2 A 1 g transitions, respectively. Cu-complex gave μeff value of 1.85 B.M, which is in agreement with square planar structures geometry about metal center [17,23]. The spectrum of the Zn(II) _ complex presented bands around 278, 382, and 435 nm attributed to π →π* and n→ π* and charge transfer, respectively.…”

Metal Complexes Derived from Mixed Azo-linked Schiff-base Ligand with Dithiocarbamate Derivative: Formation, Spectral Characterization and Biological Study

“…4 T 1 g(F)→ 4 T 1 g(P) transitions respectively whichmay confirm a distorted octahedral structure for Co(II) complex [36][37][38][39] , this result was confirmed by the magnetic moment value µeff of 5.07 B.M for the Co(II)-complex 40 . The Ni(II) complex shows a peak at 617 nm attributed to 1 A 1 g(f)→ 1 A 2 g(F), revealing a distorted square planar arrangement about Ni atom.…”

New heteroleptic palladium(II) dithiocarbamates: synthesis, characterization, packing and anticancer activity against five different cancer cell lines

“…In the spectra of the synthesized Pd(II) complexes only one strong band is observed in the region 989 cm −1 ( 1 ) and 996 cm −1 ( 2 ) which indicates that the dithiocarbamate ligands are bonded in bidentate fashion to Pd(II) centers. A new band with medium intensity at 382 cm −1 ( 1 ) and 386 cm −1 ( 2 ) corresponding to PdS is observed as was reported earlier . The PdCl stretch is observed at 312 cm −1 ( 1 ) and 308 cm −1 ( 2 ) …”

Design and Characterization of New Dinuclear Macrocyclic Dithiocarbamate Complexes by the Preparation of a Free Ligand Derived from Isopropylamine

“…The Cu(II) _ complex gives two (d-d ) absorption bands at 769 nm and at an average of 791nm, 839 nm, corresponding to 2 B 1 g → 2 B 2 g and 2 B 1 g → 2 A 1 g transitions, respectively. Cu-complex gave μeff value of 1.85 B.M, which is in agreement with square planar structures geometry about metal center [17,23]. The spectrum of the Zn(II) _ complex presented bands around 278, 382, and 435 nm attributed to π →π* and n→ π* and charge transfer, respectively.…”

Metal Complexes Derived from Mixed Azo-linked Schiff-base Ligand with Dithiocarbamate Derivative: Formation, Spectral Characterization and Biological Study

“…4 T 1 g(F)→ 4 T 1 g(P) transitions respectively whichmay confirm a distorted octahedral structure for Co(II) complex [36][37][38][39] , this result was confirmed by the magnetic moment value µeff of 5.07 B.M for the Co(II)-complex 40 . The Ni(II) complex shows a peak at 617 nm attributed to 1 A 1 g(f)→ 1 A 2 g(F), revealing a distorted square planar arrangement about Ni atom.…”

New heteroleptic palladium(II) dithiocarbamates: synthesis, characterization, packing and anticancer activity against five different cancer cell lines

“…In the spectra of the synthesized Pd(II) complexes only one strong band is observed in the region 989 cm −1 ( 1 ) and 996 cm −1 ( 2 ) which indicates that the dithiocarbamate ligands are bonded in bidentate fashion to Pd(II) centers. A new band with medium intensity at 382 cm −1 ( 1 ) and 386 cm −1 ( 2 ) corresponding to PdS is observed as was reported earlier . The PdCl stretch is observed at 312 cm −1 ( 1 ) and 308 cm −1 ( 2 ) …”

Design and Characterization of New Dinuclear Macrocyclic Dithiocarbamate Complexes by the Preparation of a Free Ligand Derived from Isopropylamine

“…The Cu(II) _ complex gives two (d-d ) absorption bands at 769 nm and at an average of 791nm, 839 nm, corresponding to 2 B 1 g → 2 B 2 g and 2 B 1 g → 2 A 1 g transitions, respectively. Cu-complex gave μeff value of 1.85 B.M, which is in agreement with square planar structures geometry about metal center [17,23]. The spectrum of the Zn(II) _ complex presented bands around 278, 382, and 435 nm attributed to π →π* and n→ π* and charge transfer, respectively.…”

Metal Complexes Derived from Mixed Azo-linked Schiff-base Ligand with Dithiocarbamate Derivative: Formation, Spectral Characterization and Biological Study

“…4 T 1 g(F)→ 4 T 1 g(P) transitions respectively whichmay confirm a distorted octahedral structure for Co(II) complex [36][37][38][39] , this result was confirmed by the magnetic moment value µeff of 5.07 B.M for the Co(II)-complex 40 . The Ni(II) complex shows a peak at 617 nm attributed to 1 A 1 g(f)→ 1 A 2 g(F), revealing a distorted square planar arrangement about Ni atom.…”