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Ten mixed‐ligand phenyl mercury(II) complexes containing 1‐methyl‐1H‐tetrazole‐5‐thiol (HmtzS) (1) and phosphine or amine ligands. These complexes fall into two groups: [PhHg(mtzS){Ph2P(CH2)PPh2}]2 (2) and [PhHg(mtzS){Ph2P(CH2)nPPh2}] (3‐6), where n varies, and [PhHg(mtzS)(diamine)] (8‐10), with diamine choices being 2,2′‐bipyridyl (Bipy, 8), 1,10‐phenathroline (Phen, 9), or ethylenediamine (en, 10). These complexes were synthesized with moderate to high yields and characterized using various techniques. Characterization data revealed that the mtzS− ligand coordinates as a monodentate ligand through the thiolate sulfur atom in all complexes, adopting a tetrahedral geometry around the Hg(II) center. Furthermore, complexes [PhHg(mtzS)] (1) and its diamine derivatives (8‐10) were assessed for hydrogen storage at 77 K using the VTI method. Results demonstrated that the incorporation of diamines improves hydrogen storage capacity at low pressure. The precursor stored (1) 2.3 wt.% at 80 bar, while the other complexes showed storage capacities ranging from 2.9 to 3.86 wt.% at pressures of 45‐60 bar. Thermodynamic properties of the [PhHg(mtzS)(Bipy)] complex was calculated at three different temperatures. The results prove that the entropy was equal to 0.50543599 J/mol H2. K while the enthalpy equal to 0.0942638 KJ/(mol H2). [ABSTRACT FROM AUTHOR]

A series of metal (II) complexes of N‐cyclohexyl amine dithiocarbamate ligand are synthesized and characterized by Fourier transform infrared, 1H, 13C NMR, mass spectroscopy, and elemental analysis. The surface structural pattern of the prepared complexes were investigated by scanning electron microscope and X‐ray diffraction techniques. The prepared complexes possessed crystalline characteristic with size average ranging from 16 to 30 nm. Moreover, the biological activity of the synthesized complexes were tested against Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. Among the prepared complexes, copper (II) complex displayed the highest activity. In addition, molecular docking study was performed against bacterial tyrosinase enzyme which showed good binding interactions and is in agreement with the experimental findings. Furthermore, the in silico toxicity studies reveal that the complexes are mostly non‐irritant with mild toxicity. Different quantum parameters including electron affinity, ionization energy, dipole moment, hardness and vibrational frequencies were calculated for the ligand and its complexes using Gaussian 09 program and B3LYP/SDD level of theory. [ABSTRACT FROM AUTHOR]

The reaction between [PtCl2(L-L)] (L-L = dppe, dppp, dppb, dppf, Phen and Bipy) or [PtCl2(PPh3)2] with 1-benzyl-3-phenylthiourea (H2BPT) in a basic medium (CHCl3/EtOH) created new coordinated square planner Pt(II) complexes with [Pt(BPT)(L-L)] (1–4,6,7) and [Pt(BPT)(PPh3)2] (5) types. These complexes were fully characterized by analytical and spectroscopic techniques (i.e., IR, UV. Vis., 1H, and 31P NMR). The results indicated that the thiourea derivative ligand act as a dianion ligand bonded through both S and N atoms in a chelating mode or as a mono-anion ligand coordinated through a sulfur atom with Pt(II) ion. Cytotoxicity activity was performed by the MTT assay to determine anti-cancer activities against MCF-7 breast cancer cells. The study indicated that IC50 values for MCF-7 cells were 10.96–78.90 µM. Additionally, the complexes [Pt(BPT)(dppe)] (1), [Pt(BPT)(PPh3)2] (5), and [Pt(BPT)2(Bipy)] (7) were investigated theoretically, where their quantum parameters were evaluated using the Gaussian 09 program using the theory of B3LYP/Def2TZVP//B3LYP/Lanl2dz. The calculation results confirmed the optimized structures of the complexes square planar geometry. However, the calculated bond lengths and angles showed a slightly distorted square planar geometry due to the trans influence of the sulfur atom. Additionally, complexes of [Pt(BPT)(dppe)] (1) and [Pt(BPT)(PPh3)2] (5) showed higher stability compared to [Pt(BPT)2(Bipy)] (7), which can be attributed to the higher back-donation of (1) and (5) complexes. Furthermore, among the three complexes, the [Pt(BPT)2(Bipy)] (7) complex possessed the lowest HOMO–LUMO gap, which may be a good candidate as the photo-catalyst material. [ABSTRACT FROM AUTHOR]

This paper reports the syntheses and spectral investigations of the new complexes [Pd(k1‐S‐ptt)2(k2‐dppmS2)] (1), [Pd(k1‐S‐ptt)2(k2‐dppp)] (2a), [Pd(k1‐N‐ptt)2(k2‐dppp)] (2b), [Pd(k1‐S‐ptt)2(k2‐dpppS2)] (3), [Pd(k1‐S‐ptt)2(k2‐dppb)] (4), [Pd(k1‐S‐ptt)2(k2‐dppf)] (5a) and [Pd(k1‐N‐ptt)2(k2‐dppf)] (5b), derived from 1‐phenyl‐5‐thiol‐1H‐tetrazole (Hptt) and diphosphine (dppmS2, dppp, dpppS2, dppb and dppf) as co‐ligand. The Hptt ligand acts as monodentate through the thiolato sulfur atom in complexes 1, 3 and 4. While in complexes 2 and 5, the Hptt ligand also acts as monodentate through the nitrogen of heterocyclic ring, or sulfur of thiol group after deprotonation, as two linkage isomers. Theoretical calculations on the all complexes were performed, isomers based on 2a, 2b and 5a, 5b reveal that each pair of isomers is isoenergetic. For the 2a and 2b complexes the energy difference was 19.92 kcal mol−1, while for the 5a and 5b complexes the difference was 11.78 kcal mol−1. These differences are relatively small and suggest that the linkage isomers may be in equilibrium in solution. The reasons for the adoption of these different coordination modes are not clear but steric factors are likely to be a major contributory factor. Further, in vitro anti‐bacterial activity and molecular docking analysis has been carried out to study the activity of the compound. [ABSTRACT FROM AUTHOR]

A tetrahedral Hg(II) diethyl dithiocarbamate (Et2Dt) complex containing triphenylphosphine (PPh3) of the composition [HgCl(κ2‐Et2Dt)2(PPh3)] (1) is prepared. Furthermore, complex (1) is used as a synthone to prepare a novel series of complexes of the following composition [Hg(Et2Dt)L(PPh3)] {L = saccharinate (2), thiosaccharinate (3), benzisothiazolinate (4), benzothiozole‐2‐thiolate (5), and benzooxazole‐2‐thiolate (6) anions}. The resulted complexes (1)–(6) are characterized by elemental analysis, molar conductivity, powder X‐ray diffraction, fourier transform Infrared, and NMR (1H and 31P) spectroscopic techniques. The Et2Dt ligand is coordinated as bidentate chelate through the sulfur atoms, whereas the L ligands are bonded as monodentate ligands to afford a tetrahedral geometry around the Hg(II) ion. Nitrogen adsorption–desorption isotherm for two of as‐prepared complexes (2) and (3) are measured first to get their Brunauer–Emmett–Teller surface area. Moreover, the mentioned two complexes are evaluated for their ability to store hydrogen gas at 77 K. However, the results of the hydrogen storage tests proved that the selected complexes are all capable of storing hydrogen, but in varying degrees, where complex (2) exhibited a storage capacity of 4.22 wt% under 88 bar. [ABSTRACT FROM AUTHOR]

Addition of 2-aminobenzothiazole and substituted derivatives to mercuric acetate in warm ethanol leads to the high yield formation of [Hg{SC6H3XN(C≡N)}]n resulting from loss of hydrogen and sulfur–carbon bond cleavage. Addition of phosphines affords a series of complexes in which the new ortho-cyano-aminothiophenolate ligands adopt three different binding modes. [ABSTRACT FROM AUTHOR]

Five bis-[5-(4'-R-phenylazo)-8-hydroxyquinoline] ruthenium complexes [RuLn · Cl2 · OH2]; where Ln = 5-(4'-R-phenylazo)-8-hydroxyquinolinol, R = OCH3 (n = 1), CH3(2), H(3), Cl(4), NO2(5), have been prepared and characterized on the basis of elemental analyses, IR, 1H NMR, ESR, thermal analysis and magnetic susceptibility measurements. The data show that these complexes exist in trans-isomeric solid form. Two inversion-related ligands and two Ru3+ atoms form a cage-like dimer. Both ligands of the dimer are bridged by a pair of inversion-related Ru-N (azodye) bonds. The octahedral coordination geometry of Ru3+ is made up of an N of pyridine, the deprotonated quinoline O atom, one of the azodye N atoms, two chlorides and one water. The ligands in the dimer are stacked over one another. In the solid state of azo-8-hydroxyquinoline, the dimers have inter-and intramolecular hydrogen bonds. Interactions between the ligands and the metal are discussed. The azo group was involved in chelation for all the prepared complexes. The effect of Hammet's constant on the ligand field parameters are also discussed and drawn. [ABSTRACT FROM AUTHOR]