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

The synthesis and structural characterization of new dithiocarbamate (DTC) ligand and some of its dinuclear transition metal complexes are described. The free dithiocarbamate ligand was prepared through several synthetic routes, including Schiff-base formation. The reaction of 2-aminopropane with terephthaldehyde leads to the formation of Schiff_base which is reduced by methanolic NaBH4 to the corresponding secondary diamine. Diamine( N,N'_ (1,4 phenylenebis (methylene)) bis(propan-2 amine)) reacts with (CS2) in a basic solution of (KOH) to provide the corresponding bis(dithiocarbamate) free_ligand, which undergoes complexation with the appropriate metal (II) chloride to constitute macrocyclic complexes. Characterization of the ligand and its complexes was achieved by FTIR, UV-Vis, melting points, conductance, magnetic susceptibility, and 1H, 13C NMR spectroscopy. The analytical and spectroscopic data were employed to obtain the suggested geometries around metal centres. These studies revealed the formation of dinuclear macrocyclic complexes of the general formula [M(L)]2 (where M= Mn(II) , Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)), with tetrahedral. geometries for Mn(II) , Fe(II), Co(II) and Zn(II), and square. planar geometry with Ni(II) and Cu(II) complexes.

Conformational polymorphism in a cobalt(II) dithiocarbamate complex

Two conformational polymorphs of (N,N-dibutyldithiocarbamato-κ2 S,S′)[tris(3,5-diphenylpyrazol-1-yl-κN 2)hydroborato]cobalt(II), [Co(C45H34BN6)(C9H18NS2)] or [TpPh2Co(S2CNBu2)], 1, are accessible by recrystallization from dichloromethane–methanol to give orthorhombic polymorph 1a, while slow evaporation from acetonitrile produces triclinic polymorph 1b. The two polymorphs have been characterized by IR spectroscopy and single-crystal X-ray crystallography at 150 K. Polymorphs 1a and 1b crystallize in the orthorhombic space group Pbca and the triclinic space group P-1, respectively. The polymorphs have a trans (1a) and cis (1b) orientation of the butyl groups with respect to the S2CN plane of the dithiocarbamate ligand, which results in an intermediate five-coordinate geometry for 1a and a square-pyramidal geometry for 1b. Hirshfeld surface analysis reveals minor differences between the two polymorphs, with 1a exhibiting stronger C—H...S interactions and 1b favouring C—H...π interactions.

(N,N-Diallyldithiocarbamato-κ2 S,S′)triphenyltin(IV) and bis(N,N-diallyldithiocarbamato-κ2 S,S′)diphenyltin(IV): crystal structure, Hirshfeld surface analysis and computational study

The crystal and molecular structures of the title organotin dithiocarbamate compounds, [Sn(C6H5)3(C7H10NS2)] (I) and [Sn(C6H5)2(C7H10NS2)2] (II), present very distinct tin atom coordination geometries. In (I), the dithiocarbamate ligand is asymmetrically coordinating with the resulting C3S2 donor set defining a coordination geometry intermediate between square-pyramidal and trigonal–bipyramidal. In (II), two independent molecules comprise the asymmetric unit, which differ in the conformations of the allyl substituents and in the relative orientations of the tin-bound phenyl rings. The dithiocarbamate ligands in (II) coordinate in an asymmetric mode but the Sn—S bonds are more symmetric than observed in (I). The resulting C2S4 donor set approximates an octahedral coordination geometry with a cis-disposition of the ipso-carbon atoms and with the more tightly bound sulfur atoms approximately trans. The only directional intermolecular contacts in the crystals of (I) and (II) are of the type phenyl-C—H...π(phenyl) and vinylidene-C—H...π(phenyl), respectively, with each leading to a supramolecular chain propagating along the a-axis direction. The calculated Hirshfeld surfaces emphasize the importance of H...H contacts in the crystal of (I), i.e. contributing 62.2% to the overall surface. The only other two significant contacts also involve hydrogen, i.e. C...H/H...C (28.4%) and S...H/H...S (8.6%). Similar observations pertain to the individual molecules of (II), which are clearly distinguishable in their surface contacts, with H...H being clearly dominant (59.9 and 64.9%, respectively) along with C...H/H...C (24.3 and 20.1%) and S...H/H...S (14.4 and 13.6%) contacts. The calculations of energies of interaction suggest dispersive forces make a significant contribution to the stabilization of the crystals. The exception is for the C—H...π contacts in (II) where, in addition to the dispersive contribution, significant contributions are made by the electrostatic forces.

Synthesis, Characterization, Spectral Studies and Antimicrobial Study on Mixed Ligand Complexes of Chloro-arsenic(III) Derived from β-Ketiminates & Piperidine Dithiocarbamate Ligand Moity

A series of Chloro-arsenic(III) complexes with N, O donor β-ketiminate ligand (L1) and S, S donor piperidine dithiocarbamate ligand (L2) have been synthesized by the reactions of AsCl3 with both ligands in equimolar ratio by stirring at room temperature in benzene solution. All these synthesized compounds have been characterized by Elemental Analysis, IR, (1H and 13C) NMR Spectral and ESI-Mass Studies. Both Ligands and their corresponding Chloro-arsenic (III) complexes have been screened for antimicrobial activity against the various bacterial (E. Coli, B. Subtalis and P. Aeruginosa) and fungal (T. Resei, P. Funiculosum and Fusarium) strains and results obtained .

(N,N-Diisopropyldithiocarbamato)triphenyltin(IV): crystal structure, Hirshfeld surface analysis and computational study

The crystal and molecular structures of the title triorganotin dithiocarbamate, [Sn(C6H5)3(C7H14NS2)], are described. The molecular geometry about the metal atom is highly distorted being based on a C3S tetrahedron as the dithiocarbamate ligand is asymmetrically chelating to the tin centre. The close approach of the second thione-S atom [Sn...S = 2.9264 (4) Å] is largely responsible for the distortion. The molecular packing is almost devoid of directional interactions with only weak phenyl-C—H...C(phenyl) interactions, leading to centrosymmetric dimeric aggregates, being noted. An analysis of the calculated Hirshfeld surface points to the significance of H...H contacts, which contribute 66.6% of all contacts to the surface, with C...H/H...C [26.8%] and S...H/H...H [6.6%] contacts making up the balance.

Stabilization of Silver Nanoparticles with a Dithiocarbamate Ligand and Formation of Nanocomposites by Combination with Polythiophene Derivative Nanoparticles

Spherical morphology for silver nanoparticles (Ag NPs) stabilized with dithiocarbamate (DTC) by reducing silver nitrate with sodium borohydride was obtained, while the addition of sodium citrate and hydrogen peroxide allowed the formation of silver nanotriangles (Ag NTs). Solutions of bright yellow and blue colors characteristic of both morphologies were observed. UV-vis optical analysis of NPs stabilized with DTC showed a plasmonic absorption band at 393 nm characteristic for spherical morphology, while two bands were observed at 332 nm and 762 nm, and a shoulder around 500 nm for the triangular morphology; with these spectra each morphology was confirmed. In these spectra an absorption band between 250 and 260 nm confirms the presence of DTC ligand. The stability of the NPs was achieved using an 8.69 × 10-3 mM solution of 4-(ethylaminodithiocarbamate) methylpyridine di-n-butyltin (IV) through a transmetallation reaction. Silver nanoparticles (Ag NPs) with spherical morphology of average diameter of 12.7 ± 1.2 nm and triangular morphology with 28.9 ± 0.8 nm for each side of the triangles were analyzed by high resolution scanning electron microscopy (HR-SEM). UV-vis spectra also showed the stability of NPs with DTC for more than three months. A copolymer derived of 3-hexylthiophene with (E)-2-(ethyl(4-((4-nitrophenyl) diazenyl) phenyl) amino) ethyl 2-(thiophen-3-yl) acetate (PA) was tested to get polymer NPs by reprecipitation method using THF/water systems. PA Polymer NPs having average diameter of 9.0 ± 1.7 nm were found. By quick and easy procedure, the formation of nanocomposite (NC) of spherical Ag NPs and PA polymer NPs was reached. This NC could be used as imaging agent, electrochemical biosensor, and photonic and optoelectronic device materials.

Crystal structures and Hirshfeld surface analyses of (N-hexyl-N-methyldithiocarbamato-κ2 S,S′)triphenyltin(IV) and [N-methyl-N-(2-phenylethyl)dithiocarbamato-κ2 S,S′]triphenyltin(IV)

The crystal and molecular structures of two triphenyltin dithiocarbamate compounds, viz. [Sn(C6H5)3(C8H16NS2)], (I), and [Sn(C6H5)3(C10H12NS2)], (II), are described. The dithiocarbamate ligand in each molecule coordinates in an asymmetric fashion resulting in heavily distorted tetrahedral C3S coordination geometries for the Sn atoms, with the distortions traced to the close approach of the non-coordinating thione-S atom. The molecular packing in both compounds features C—H...π(Sn-phenyl) interactions. In (I), the donors are Sn-phenyl-C—H groups leading to centrosymmetric aggregates, while in (II), the donors are both Sn-phenyl-C—H and methyl-C—H groups leading to supramolecular chains propagating along the b axis. The identified aggregates assemble into their respective crystals with no directional interactions between them. An analysis of the Hirshfeld surfaces show distinctive patterns, but an overwhelming predominance (>99% in each case) of H...H, C...H/H...C and S...H/H...S contacts on the respective Hirshfeld surface.

Synthesis, Characterization and Biological Evaluation of New Dithiocarbamate Ligand and Its Complexes with some Metal Ions

New bidentate dithiocarbamate ligand (NaL) namely [Sodium-2-(((3-methyl -4- “(2,2,2-tri fluoro ethoxy) pyridin-2”-yl) methyl) sulfinyl)-1H-benzoimidazole -1-carbodithioate] was prepared. This free ligand was synthesized from the reaction of a (RS)-2-([3-methyl -4-(2,2,2-tri fluoroethoxy) pyridin-2-yl] methyl sulfinyl)-1H benzoimidazole, CS2 and NaOH in methanol as solvent. From reaction of dithiocarbamate salt (NaL) with metal ions (M); Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pd(II)”, have obtained the DTC complexes at general molecular formula [M(L)2(H2O)2] and [Pd(L)2]. To characterize the ligand and its complexes, used different analyses methods such FTIR, UV-Vis, elemental microanalysis, atomic absoreption, magnetic susceptibility, conductance, melting points, 1H- 13C- NMR spectroscopy, thermal analysis and mass spectrum. These studies indicated the formation of DTC complexes which their geometries about metal centers are octahedral; except Pd-complex is square planer. The bacterial activity evaluation against investigated bacterial species indicated that the metal complexes are more active than the free ligand when compared them.