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The chemistry of copper(I) halides (CuX) with furan-2-carbaldehyde-N1-substituted thiosemicarbazones {(C4H3O)HC2N3N2H–C1(S)N1HR, Hftsc-N1HR} in presence of triphenyl phopshine is described. For methyl and ethyl substituents (R) at N1 atom, and with X = I, Br, Cl, the halogen-bridged dimers, namely, [Cu2(μ-X)2(η1-S-Hftsc-N1HR)2(PPh3)2] (R, X: Me, I, 1, Br 2, Cl 3; Et, I 4, Br 5, Cl 6) have been obtained.However, the presence of phenyl substituent at N1 has favored a three coordinate complex, [CuI(η1-S-Hftsc-N1HPh)2] 7, and with copper(I) bromide/and chloride, it has formed sulfur-bridged dimers, [Cu2X2(η1-Hftsc-N1HPh)2(μ-S-Hftsc N1HPh)2] (X = Br 8, Cl 9). In the latter three complexes (7–9), the Ph3P ligand did not take part in coordination. All these complexes have been characterized with the help of elemental analysis, IR, 1H NMR spectroscopy and X-ray crystallography (1–3, 5, 7 and 9). The bonding and nuclearity of complexes has been found to vary with the substituents at N1 atom. The intermolecular interactions have formed one dimensional (1, 9) and two dimensional (2, 3 and 5) networks. [ABSTRACT FROM AUTHOR]

The nuclearity, bonding and H-bonded networks of copper(I) halide complexes with thiophene-2-carbaldehyde thiosemicarbazones {(C4H3S)HC2 ＝N3–N(H)–C1(＝S) N1HR} are influenced by R substituents at N1 atom. Thiophene-2-carbaldehyde-N1-methyl thiosemicarbazone (HttscMe) or thiophene-2-carbaldehyde-N1-ethyl thiosemicarbazone (HttscEt) have yielded halogen-bridged dinuclear complexes, [Cu2(μ-X)2(η1-S-Htsc)2(Ph3P)2] (Htsc, X: HttscMe, I, 1; Br, 2; Cl, 3; HttscEt, I, 4; Br, 5; Cl, 6), while thiophene-2-carbaldehyde-N1-phenyl thiosemicarbazone (HttscPh) has yielded mononuclear complexes, [CuX(η1-S-HttscPh)2] (X, I, 7a; Br 8; Cl, 9) and a sulfur bridged dinuclear complex, [Cu2(μ-S-HttscPh)2(η1-S-HttscPh)2I2] 7b co-existing with 7a in the same unit cell. These results are in contrast to S-bridged dimers [Cu2(μ-S-Httsc)2(η1-Br)2(Ph3P)2]·2H2O and [Cu2(μ-S-Httsc)2(η1-Cl)2(Ph3P)2]·2CH3CN obtained for R=H and X=Cl, Br (Httsc=thiophene-2-carbaldehyde thiosemicarbazone) as reported earlier. The intermolecular CHPh⋯π interaction in 1–3 (2.797Å, 1; 3.264Å, 2; 3.257Å, 3) have formed linear polymers, whereas the CHPh⋯X and N3⋯HCH interactions in 4–6 (2.791, 2.69Å, 5; 2.776, 2.745Å, 6, respectively) have led to the formation of H-bonded 2D polymer. The PhN1H⋯π, interactions (2.547Å, 8, 2.599Å, 9) have formed H-bonded dimers only. The Cu⋯Cu separations are 3.221–3.404Å (1–6). [Copyright &y& Elsevier]

Abstract: The reactions of silver(I) halides (Cl or Br) with thiophene-2-carbaldehyde N1-methyl thiosemicarbazone (HttscMe) in the presence of Ph3P (1:1:1 molar ratio) yield halogen-bridged dimers, [Ag2(μ-X)2(η1-S-HttsMe)2(PPh3)2] (X=Cl, 1; Br, 2). The use of 2,2′-bipyridine in lieu of Ph3P in the reaction of silver(I) chloride with HttscMe yields the sulfur-bridged dimer, [Ag2(μ-S-HttscMe)2(η1-HttsMe)2]·2CHCl3 3. The substituents have altered the nature of bridge between the two silver atoms. The Ag···Ag separation (3.4867(5)Å) in complex 3 is less than that in the halogen-bridged dimers (3.734(4)Å1; 3.746(5)Å2). Unlike PPh3 the co-ligand 2,2′-bipyridine did not coordinate to the silver center, but was necessary for crystallization in the reaction with the thio-ligand. NMR spectroscopy revealed that the complexes remained unchanged in the solution state (CDCl3). [Copyright &y& Elsevier]

Abstract: This review describes the coordination chemistry of thiosemicarbazones and covers all the metals for which complexes are reported. The coordination compounds of d-block, p-block and f-block elements are discussed with respect to their bonding and structures. The description of work is group by group and with a given metal, coordination compounds of all the ligands under purview are described. A brief description of synthesis and spectroscopy of complexes is also given. Several of complexes are mononuclear, with distorted tetrahedral, square planar, square pyramid or octahedral as their common geometries. Dimers, trimers, tetramers, as well as complexes of higher nuclearity are also reported. Variable bonding properties, metallation, metal–metal interactions, role of solvents/other factors in stabilization of sulfur-bridging in coinage metals, and the nature of substituents at azomethine carbon are other interesting features of the review. Further, biological and analytical applications of the ligands/complexes are included in brief so as to indicate the importance of ligands under consideration. The literature survey is complete to December 2007, and some papers of more recent origin are included. [Copyright &y& Elsevier]