Metal-sulfur Bond Research Articles

Standard enthalpy of formation of di-isobutyldithiocarbamate complexes of zinc-group elements and mean M-S bond-dissociation enthalpies

The standard enthalpies of formation of crystalline di-isobutyldithiocarbamate complexes of Zn, Cd and Hg(II) have been derived by solution calorimetry at 298.15 K, giving values −526.06±3.30, −468.07±3.23 and −310.15±3.56 kJ mol −1, respectively. The corresponding molar enthalpies of sublimation, 283±2, 281±2 and 247±1 kJ mol −1, were estimated by means of differential scanning calorimetry. From the standard molar enthalpies of formation of the gaseous chelates, −243±4, −187±4 and −63±4 kJ mol −1 the homolytic 137±4, 118±4 and 75±4 kJ mol −1 and heterolytic 700±4, 646±4 and 682±4 kJ mol −1 mean metal-sulphur bond enthalpies were calculated. The homolytic enthalpies decrease from zinc to mercury and depend on the nature of the radical attached to the nitrogen of the ligand.

Thermochemistry of adducts of N,N-dimethylthioacetamide and of N,N-dimethylthioformamide with antimony triiodide or bismuth triiodide at the temperature 298.15 K

The new adducts MI3·L (M = Sb or Bi; L = N,N -dimethylthioacetamide (dmta) or N,N-dimethylthioformamide (dmtf), were isolated, characterized, and studied through reaction-solution calorimetry at the temperature 298.15 K: MI3(cr)+L(l, cr) = MI3·L(cr); ΔrHom(kJ·mol-1): SbI3·dmta, -10.58±0.14; SbI3·dmtf, -14.90±0.14; BiI3·dmta, -9.96±0.29; and BiI3·dmtf, -15.19±0.41. Using ΔrHom and the standard molar enthalpies of formation of ligands and triiodides, the standard molar enthalpies of formation of the crystalline thioamide adducts were calculated; their values for this sequence are: (-177.6, -131.3, -226.6, and -181.2) kJ·mol-1. The mean metal-sulphur bond enthalpies for the same sequence: (112, 117, 144, and 150) kJ·mol-1, were also calculated.

Hydrodesulfurization of Dibenzothiophene Catalyzed by Supported Metal Carbonyl Complexes. (Part 1). Hydrodesulfurization Catalysts Prepared from Alumina-supported Group VI Metal Carbonyl Complexes.

Hydrodesulfurization (HDS) of dibenzothiophene (DBT) catalyzed by alumina-supported metal carbonyl complexes (Mo(CO)6, Cr(CO)6, W(CO)6) was investigated in a pressurized flow system. Catalysts prepared by activation of metal carbonyl complexes-triethylamine(NEt3)-ethanethiol(EtSH)/Al2O3 systems where metal carbonyls were reacted with NEt3 and EtSH to give anionic complexes with metal-sulfur bonds were found to be active in HDS of DBT. When a Mo(CO)6-NEt3-EtSH/Al2O3 system was activated by H2 or H2S, the catalytic activity was the highest among catalysts derived from supported-metal carbonyls and the conversion of DBT at 300°C was 43%, which was higher than that over a conventional molybdena-alumina. From NO chemisorption and XPS measurement, it was deduced that hydrogenation of a Mo(CO)6-NEt3-EtSH/Al2O3 system would give alumina-supported MoS2-x species which was active in HDS of DBT.

L-edge x-ray absorption spectroscopy of Pyrococcus furiosus rubredoxin

X-ray absorption spectroscopy has been used to probe the frozen solution structure of the metal site in Pyrococcus furiosus rubredoxin in the native, iron-containing protein and in zinc- and mercury-substituted proteins. For all samples studied, the spectra have been interpreted in terms of a single shell of coordinated sulfur, with approximately tetrahedral coordination. For the native protein we obtain Fe-S bond-lengths of 2.29 and 2.33 A for oxidized and reduced proteins, respectively. These values are in excellent agreement with those previously obtained from X-ray crystallography. The metal-substituted rubredoxins possess metal-sulfur bond lengths of 2.34 and 2.54 A for the zinc- and mercury-substituted proteins, respectively.

Thioamide adducts of zinc-group chlorides—a thermochemical study

The standard molar enthalpies ΔrH°m of the adducts of zinc-group chlorides with thioacetamide (ta) and thiobenzamide (tb) have been determined through reaction-solution calorimetry at the temperature 298.15 K: MCl2(cr) + vL(cr) = MCl2 · vL(cr); ΔrH°m/(kJ · mol−1): ZnCl2 · 2ta, −(62.09±0.33); CdCl2 · 2ta, −(45.77±0.30); HgCl2 · ta, −(61.59±0.28); ZnCl2 · 2tb, −(52.26±0.69); CdCl2 · tb, −(19.44±0.20); and HgCl2 · 2tb, −(76.81±0.09). From ΔrH°m the standard molar enthalpies of formation of the crystalline thioamide adducts were calculated; the values decrease from zinc to mercury within the ta: { −(623.2±0.9) to −(358.9±1.1)} kJ · mol−1 and tb: {−(377.0±3.1) to −(210.7±3.2)} kJ · mol−1, series. The mean metal-sulphur bond dissociation enthalpies decrease with increase of number of ligands, and are roughly of the same size as the equivalent metal-oxygen bond for zinc and cadmium. The softer behaviour of mercury favours its bonding to the sulphur donor atom.

Thermochemical features of di-n-propyldithiocabamate chelates of zinc-group elements

Solution-reaction calorimetry was used to determine the standard molar enthalpy of formation at 298.15 K of crystalline [M(S2CNPrn2)2](M = Zn, Cd or Hg): –440.68 ± 2.85, –396.71 ± 2.60 and –240.50 ± 2.40 kJ mol–1, respectively. The enthalpies of sublimation, 147 ± 2, 199 ± 1 and 200 ± 2 kJ mol–1, were estimated by means of differential scanning calorimetry. From the standard molar enthalpies of formation of the gaseous chelates, –294 ± 4, –198 ± 3 and –41 ± 3 kJ mol–1, the homolytic 182 ± 3, 154 ± 3 and 102 ± 3 kJ mol–1 and heterolytic 745 ± 3, 681 ± 3 and 709 ± 3 kJ mol–1 mean metal-sulfur bond enthalpies were calculated. The homolytic enthalpies decrease from zinc to mercury and are dependent on the nature of the radical attached to the nitrogen of the ligand.

(NH4)2[Re2S16], a Soluble Metal Sulfide with Interesting Electronic Properties and Unusual Reactivity

A strong transannular ReRe interaction and reactive metal–sulfur bonds characterize the title anion 1 (shown on the right without the two chelating S4-ligands). This surprising result explained by the existence of molecular orbitials arising from Re 5d and S 3p functions of similar energy are not only Re–Re bonding but also markedly delocalized. These findings underline the importance of the role of the metal center, especially in catalytically active metal sulfides.

SYNTHESIS AND REACTIONS OF NOVEL ORGANOSULFUR COMPOUNDS HAVING A HIGHLY STERICALLY BULKY GROUP, 2,4,6-TRIS[BIS(TRIMETHYLSILYL)METHYL]PHENYL

Abstract Novel cyclic metallatetrasulfides containing Group 14 metals have been synthesized by the thermal reactions of the corresponding metal hydrides substituted by the title new steric protection group. The structure of newly obtained metallacyclopolysulfides is of great interest in comparison with that of the previously reorted di-π-cyclopentadienylmetal pentasulfides of titanium(IV) and vanadium (IV). Attempts to prepare the metal-sulfur double bond compounds from the metallacyclopolysulfides are also described.

Effects of sulphur substituents on the geometries of dipalladium μ-thiolato complexes: Crystal structures of Pd 2Cl 2(μ-Cl)(μ-SR)(PMe 3) 2 (R  Me, t-Bu and Ph) and Pd 2Cl 2(μ-SPh) 2(PEt 3) 2

The mono(μ-alkylthiolato) complexes, cis-Pd 2Cl 2(μ-Cl)(μ-SR)(PMe 3) 2 (R  Me, 1; t-Bu, 2) are obtained as the exclusive products of the reaction of acetone solutions of trans-[PdCl(μ-Cl)(PMe 3)] 2 with the corresponding thiols at 25°C, whereas reaction with stoichiometric amounts of thiophenol gives mixtures of cis-Pd 2Cl 2(μ-Cl)(μ-SPh)(PMe 3) 2 ( 3) and trans-Pd 2Cl 2(μ-SPh) 2(PMe 3) 2 ( 5). Reaction of trans-[PdCl(μ-Cl)(PR 3)] 2 with thiophenol in a 1 : 2 stoichiometry gives exclusively trans-Pd 2Cl 2(μ-SPh) 2(PR 3) 2 (R = Et, 4; Me, 5). The molecular structures of 1, 2, 3·CH 2Cl 2 and 4 have been determined by X-ray diffraction. Complexes 1 and 2 have non-planar geometries with dihedral angles of 140 and 146°, respectively, between the coordination planes of the palladium atoms. By contrast, the μ-arylthiolato complexes are planar with dihedral angles of 180° between the coordination planes of the palladium atoms. The PdS bond distances 2.262(2)–2.272(2) Å in complexes 1 and 2 are significantly shorter than the PdS distances in 3, 2.288(2) and 2.301(2) Å, indicating enhanced metal-sulphur bonding in the alkylthiolato complexes. The bent geometries of the alkylthiolato complexes as well as the dichotomy of cis and trans phosphine geometries preferred by M 2Cl 2(μ-SR) 2(PR′ 3) 2 (M = Pd, Pt) alkylthiolato and arylthiolato complexes, respectively, are discussed in view of the enhanced sulphur-metal donor interactions in the alkylthiolato complexes. The isolation of mono(μ-thiolato) complexes from the reaction of trans-[PdCl(μ-Cl)(PMe 3)] 2 with alkylthiols and not arylthiols is also accounted for by the additional stabilization of the metal-sulphur bonds in the alkylthiolato complexes. Crystallographic data : for 1, orthorhombic, Pbc2 1, Z = 4, a = 11.630(6), b = 11.667(3), c = 12.816(4) Å, V = 1739(1) Å 3, ϱ calc. = 1.980 g cm −3; for 2, orthorhombic, P2 1 cn, Z = 4, a = 8.158(3), b = 10.345(3), c = 24.106(6) Å, V = 2035(1) Å 3, ϱ calc. = 1.830 g cm −3; for 3·CH 2Cl 2, monoclinic C2/2, Z = 8, a = 27.38(1), b = 11.477(9), c = 16.506(7) Å, β = 124.12(3)°, V = 4294(4) Å 3, ϱ calc. = 1.924 g cm −3; for 4, triclinic P 1 , Z = 2, a = 8.694(5), b = 9.570(6), c = 10.203(7) Å, α = 68.72(5), β = 76.86(5), γ = 85.27(5)°, V = 770.3(8) Å 3, ϱ calc. = 1.592 g cm −3.

Metal-sulphur bond enthalpy determination of di-n-butyldithiocarbamate chelates of zinc, cadmium and mercury

The standard molar enthalpies of formation of crystalline [M(S2CNBun2)2](M = Zn, Cd or Hg), determined through reaction-solution calorimetry at 298.15 K, were found to be –471.23 ± 3.90, –440.74 ± 3.79 and –319.29 ± 3.38 kJ mol–1, respectively. The corresponding molar enthalpies of sublimation, 107 ± 3, 123 ± 3 and 195 ± 3 kJ mol–1, were estimated by means of differential scanning calorimetry. From the standard molar enthalpies of formation of the gaseous chelates, –364 ± 5, 318 ± 5 and –124 ± 5 kJ mol–1, the homolytic and heterolytic mean metal-sulphur bond enthalpies were calculated. The homolytic enthalpies decrease from zinc to mercury, while the heterolytic values are almost constant.

Thermal stability and reaction of chalcogen-containing metallocenic compounds with elemental chalcogens

Dissymmetrical four-membered bimetallocenacycles (t-BuC5H4)2M(μ-S)2M′-(RC5H4)2(M, M′ = Zr, Hf; R = H, t-Bu) have been prepared and found to give redistribution products in solution at 190°C; identification of these products shows that the reaction involves exclusive cleavage of a metal-sulfur bond. Elemental sulfur and selenium react with chalcogen-containing complexes. The reaction is shown to involve the introduction of chalcogenic species in place of the σ-ligands of the complex to give either four-membered bimetallic complexes or catenated pentachalcogen metallocenic compounds. Some examples of insertion of sulfur and tellurium into the zirconium-methyl bond are also described.

ChemInform Abstract: Synthesis and Characterization of (HgAu(CH2SPPh2CH2)2)PF6, the First Example of Structurally Characterized Carbene Double Insertions into Metal‐Sulfur Bonds.

ChemInformVolume 20, Issue 39 Organoelement Compounds ChemInform Abstract: Synthesis and Characterization of (HgAu(CH2SPPh2CH2)2)PF6, the First Example of Structurally Characterized Carbene Double Insertions into Metal-Sulfur Bonds. S. WANG, S. WANG Dep. Chem., Tex. A&M Univ., College Station, TX 77843, USASearch for more papers by this authorJ. P. JUN. FACKLER, J. P. JUN. FACKLER Dep. Chem., Tex. A&M Univ., College Station, TX 77843, USASearch for more papers by this author S. WANG, S. WANG Dep. Chem., Tex. A&M Univ., College Station, TX 77843, USASearch for more papers by this authorJ. P. JUN. FACKLER, J. P. JUN. FACKLER Dep. Chem., Tex. A&M Univ., College Station, TX 77843, USASearch for more papers by this author First published: September 26, 1989 https://doi.org/10.1002/chin.198939273Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume20, Issue39September 26, 1989 RelatedInformation

Carbene double insertions into metal-sulfur bonds. Synthesis and characterization of [HgAu(CH2SPPh2CH2)2]PF6, the first example of structurally characterized carbene double insertions into metal-sulfur bonds

Carbene double insertions into metal-sulfur bonds. Synthesis and characterization of [HgAu(CH2SPPh2CH2)2]PF6, the first example of structurally characterized carbene double insertions into metal-sulfur bonds

Polarographic study of the dipropyldithiophosphinate complexes of Pd(II), Pb(II), Cd(II), and Zn(II) ions

The complexes of the dithiophosphinic acids with Pd(II), Pb(II), Cd(II), and ZN(II) in a toluene-ethanol medium produce single polarographic waves. The half-wave potential is a linear function of the ligand concentration. The stabilities of these chelates, which are characterized by a sulphur-metal bond, are in the order: Pd(II) > Pb(II) > Cd(II) > Zn(II).

Energetics of metal-sulfur bonds in the complexes M(.eta.5-C5H5)2(SC2H5)2 (M = Ti, W) and W(.eta.5-C5H5)2(SC6H5)2. Molecular structure of Ti(.eta.5-C5H5)2(SC2H5)2

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEnergetics of metal-sulfur bonds in the complexes M(.eta.5-C5H5)2(SC2H5)2 (M = Ti, W) and W(.eta.5-C5H5)2(SC6H5)2. Molecular structure of Ti(.eta.5-C5H5)2(SC2H5)2Maria J. Calhorda, Maria A. A. F. de C. T. Carrondo, Alberto R. Dias, Carlos F. Frazao, Michael B. Hursthouse, Jose A. Martinho Simoes, and Clementina TeixeiraCite this: Inorg. Chem. 1988, 27, 14, 2513–2518Publication Date (Print):July 1, 1988Publication History Published online1 May 2002Published inissue 1 July 1988https://doi.org/10.1021/ic00287a028RIGHTS & PERMISSIONSArticle Views66Altmetric-Citations26LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (734 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Carbonyl insertion into a CS bond and complex dimerization during reaction of the dithioesters SC(Me)SEt and SC(Ph)SMe with iron carbonyl complexes

Dithioesters react with pentacarbonyliron or nonacarbonyldiiron under UV irradiation to give three classes of compounds. In the metalmetal-bonded complexes [Fe 2(CO) 6{;SC(R 1)SR 2};] (R 1  Me or Ph; R 2  Et or Me) which belong to the first class, the iron atoms are doubly-bridged by a CS unit and the original bicovalent sulphur atom of the intact dithioester unit. Similar metal links also exist in the complex [Fe 2(CO) 6{;μ-η 2-S CS(CH 2) 2S - S,S′};]( Fe-Fe) (I), formed from a trithiocarbonate (R 1R 2  SCH 2CH 2) and [Fe(CO) 5], as confirmed by single-crystal X-ray diffraction. The nature of the bonding in the second class of compounds was established by determining the crystal structure of the dimeric compound [Fe(CO) 3{;SC(Ph)SMe};] 2 (V) in which there is no metal-metal bond but each coordinated ligand forms a non-symmetrical dative sulphur-metal bond to the other iron atom. An X-ray crystal structure of a member of the third type of compound [Fe 2(CO) 6{;SC(R 1)C(O)SR 2};] (R 1  Ph; R 2 7z.dbnd; Me) (VI), shows that it is the result of carbonyl insertion into the C-SR 2 bond of the ligand.

Catalytic interaction of ethylene and propylene with H2S

The activity of metal sulfides in the interaction of olefins with H2S has been found to depend on the strength of metal-sulfur bonds. It has been revealed that nonstoichiometric sulfur affects the properties of sulfide catalysts.

Phosphinothioformamides - A Class of Versatile Ambidentate Complex Ligands

Abstract Secondary and tertiary phosphinothioformamides have proved to be flexible, ambidentate complex ligands. Structural differences in solid and dissolved state have been made observable by carbon-13 CP-MAS NMR techniques. The (CO)4M(PS) complexes (M = Cr, Mo, W) react with mono-dentate ligands under reversible fission of the metal-sulfur bond which favours the application of such systems in metal-catalyzed syntheses. We suggest three ways for the preparation of chiral phosphinothioformamides which show a high diastereoselectivity upon coordination to prochiral half-sandwich complexes.

Co-ordination abilities of thioamide analogues of amino acids and peptides. Copper(II) and nickel (II) complexes

Potentiometric and spectroscopic results for CuII and NiII complexes with leucine-N-methylamide, methionine-N-methylamide, their thiocarbonyl analogues, and for (phenylalanyl)methionine-N-methylamide are reported. For solubility reasons only spectroscopic results in ethanol solutions are presented for CuII complexes with the last of these. Thiocarbonyl was found to be much more effective in metal ion binding than carbonyl donor and the complexes formed with metal–sulphur bonds are several orders of magnitude more stable than the respective species with carbonyl binding. The sulphur donation, however, does not prevent thioamide nitrogen deprotonation and co-ordination at high pH.

Vibrational spectroscopic study of the thermal degradation of polyarylene metallosulphides

The authors have studied the processes of thermal degradation of polyarylene metallo-sulphides in vacuo and in presence of oxygen by IR spectroscopy in the region 150–4000 cm −1. From analysis of the low-frequency vibratory spectra (290–400 cm −1) it has been established that thermal degradation begins with rupture of the sulphur—metal bond. The differences in thermal degradation in vacuo and in presence of oxygen depending on the nature of the metal and the presence in the chain of a heteroatomic bridge are discussed.