- Reaction of a stable germabenzene with chalcogens: Synthesis and structure of a novel germanium analog of pentathiepane, 1,2,3,4,5,6-pentathiagermepane
-
Treatment of a germabenzene (4) bearing a Tbt group (Tbt=2,4,6-tris[bis(trimethylsilyl)methyl]phenyl) with elemental sulfur gave a 1,2,3,4-trithiagermolane (5) together with a novel 1,2,3,4,5,6-pentathiagermepane (6), which is the germanium analog of pentathiepane. On the other hand, the reaction of 4 with elemental selenium gave only 1,2,3,4-triselenagermolane (7). All the newly obtained polychalcogenides containing a germanium atom were characterized by NMR spectroscopy and elemental analysis. The molecular structures of 5 and 6 were determined by X-ray crystallographic analysis. In addition, the thermolyses of 5 and 6 were examined.
- Nakata, Norio,Takeda, Nobuhiro,Tokitoh, Norihiro
-
-
Read Online
- Highly efficient synthesis of 2-mercaptobenzothiazole derivatives in water: Metal sulfide-disulfide dynamic interchange reaction
-
A convenient and efficient method for the synthesis of 2-mercaptobenzothiazoles from disulfide and CS2 mediated by a metal sulfide in water is described. This synthetic methodology could be used to prepare diverse 2-mercaptobenzothiazole derivatives in good to excellent yields. In this paper, the concept of metal sulfide-disulfide dynamic interchange reaction was put forward. Then the intermediates of the interchange reaction between NaHS and a disulfide were detected by LC-MS, which demonstrated that the S-S bond of the disulfide could be broken by the metal sulfide through the dynamic interchange reaction. In addition, NaHS was eventually transformed into sulfur S8 by the dynamic interchange reaction. Moreover, the underlying mechanism of 2-mercaptobenzothiazole formation is proposed, in which NaHS not only acts as an S-S bond cleaving agent but also as an activator of CS2. As a result, a novel synthetic route for the preparation of sulfur-containing heterocycles from a disulfide is developed.
- Lou, Chunqing,Zhu, Ning,Fan, Ronghua,Hong, Hailong,Han, Limin,Zhang, Jianbin,Suo, Quanling
-
-
Read Online
- Sonochemistry: C3S2 originated by ultrasounding carbondisulfide
-
Pure carbondisulfide was treated with ultrasound of a frequency of 20 kHz. Consequently small amounts of C3S2, S6, S7, and S8 were obtained, which could be seperated gas-chromatographically and detected by mass spectroscopy. The yields were approximately proportional to the period of influence. Johann Ambrosius Barth 1996.
- Quellhorst, Heike,Binnewies, Michael
-
-
Read Online
- A Multiunit catalyst with synergistic stability and reactivity: A polyoxometalate-metal organic framework for aerobic decontamination
-
A combination of polyanion size and charge allows the Keggin-type polyoxometalate (POM), [CuPW11O39]5-, a catalyst for some air-based organic oxidations, to fit snuggly in the pores of MOF-199 (HKUST-1), a metal-organic framework (MOF) with the POM countercations residing in alternative pores. This close matching of POM diameter and MOF pore size in this POM-MOF material, [Cu3(C9H3O 6)2]4[{(CH3)4N} 4CuPW11O39H] (1), results in a substantial synergistic stabilization of both the MOF and the POM. In addition, this heretofore undocumented POM-MOF interaction results in a dramatic increase in the catalytic turnover rate of the POM for air-based oxidations. While 1 catalyzes the rapid chemo- and shape-selective oxidation of thiols to disulfides and, more significantly, the rapid and sustained removal of toxic H 2S via H2S + 1/2 O2 → 1/8 S8 + H2O (4000 turnovers in 20 h), the POM or the MOF alone is catalytically slow or inactive. Three arguments are consistent with the catalytic reactions taking place inside the pores. POM activation by encapsulation in the MOF likely involves electrostatic interactions between the two components resulting in a higher reduction potential of the POM.
- Song, Jie,Luo, Zhen,Britt, David K.,Furukawa, Hiroyasu,Yaghi, Omar M.,Hardcastle, Kenneth I.,Hill, Craig L.
-
-
Read Online
- Transformation of 2-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)-6-ethoxy-4-phenylpyridine-3,5-dicarbonitrile into 4-aminopyrido[2,3-d]pyrimidines and 2-(pyrid-2-yl)guanidines
-
The reactions of 2-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)-6-ethoxy-4-phenylpyridine-3,5-dicarbonitrile (14) with a range of primary and secondary amines are investigated. Treatment with n-BuNH2 and BnNH2 gave 1,3-di-n-butyl- and 1,3-dibenzyl-2-(3,5-dicyano-6-ethoxy-4-phenylpyrid-2-yl)guanidines 15a (32%) and 15b (82%), respectively. While treatment with Et2NH, n-Pr2NH or Bn2NH gave the analogous 4-dialkylaminopyrido[2,3-d]pyrimidines 16c-e in high yields. Treatment of the dithiazole 14 with pyrrolidine, piperidine or morpholine gave the analogous 4-dialkylaminopyrido[2,3-d]pyrimidines 16f-h, the 2-aminopyridine 13 and 2-(diamino-1-ylmethyleneamino)-6-ethoxy-4-phenylpyridine-3,5-dicarbonitriles 15f-h. The 4-dialkylaminopyrido[2,3-d]pyrimidines 16f-h are converted to the 2-(dialkylamino-1-ylmethyleneamino)-6-ethoxy-4-phenylpyridine-3,5-dicarbonitriles 15f-h upon further reaction with excess dialkylamines. The structure and origins of the two side products 17 and 18 are also discussed. Tentative mechanisms for these transformations are proposed.
- Kalogirou, Andreas S.,Michaelidou, Sophia S.,White, Andrew J.P.,Koutentis, Panayiotis A.
-
-
Read Online
- Mechanochemical reactions of elementary sulfur and iron sulfides with hydrogen, oxygen, and water
-
Mechanochemical reactions of elementary sulfur and iron sulfides with hydrogen, oxygen, and water were studied. Three reactions were discovered: (1) between elementary sulfur and dihydrogen, (2) between pyrite and dihydrogen, and (3) between elementary su
- Pavelko
-
-
Read Online
- Unexpectedly efficient SO2 capture and conversion to sulfur in novel imidazole-based deep eutectic solvents
-
An innovative strategy for sustainable SO2 capture and conversion in novel imidazole-based deep eutectic solvents (DESs) is demonstrated in this work. These DESs exhibit an extremely high SO2 loading capacity (up to 1.39 g g-1/
- Zhao, Tianxiang,Liang, Jian,Zhang, Yating,Wu, Youting,Hu, Xingbang
-
-
Read Online
- Syntheses, structures and third-order nonlinear optical properties of heterometal and homometal clusters containing iron
-
Both the heterometal cluster {[FeMo2O10(FRA) 4(DMF)4]·2DMF} (1) (FRA = α-furoic acid) and the homometal cluster {Fe[DTC]4} (2) (DTC = diethyl-dithiocarbamate) were successfully synthesized by low-temperature solid-state reactions. X-ray single-crystal diffraction studies suggest that compound 1 is a hexanuclear cluster including two solvent DMF molecules, with α-furoic acid and DMF as auxiliary ligands, and compound 2 is a dinuclear neutral cluster. The two compounds were characterized by elemental analyses, IR spectra and UV-Vis spectra. The third-order nonlinear optical (NLO) properties of the clusters were also investigated and all exhibited nice nonlinear absorption and self-defocusing performance with moduli of the hyperpolarizabilities 1.21 × 10-31 esu for 1 and 5.123 × 10-31 esu for 2.
- Lu, Jing,Lü, Chang-Hai,Yu, Jie-Hui,Xu, Ji-Qing,Li, Yong,Zhang, Xiao,Wang, Tie-Gang,Yang, Qing-Xin
-
-
Read Online
- Photodegradation of methyl thioglycolate particles as a proxy for organosulphur containing droplets
-
Understanding the formation and transformation of sulphur-rich particles is of prime importance since they contribute to the global atmospheric sulphur budget. In this work, we performed a series of experiments on a photoactive organosulphur compound namely, methyl thioglycolate, as a model of an organosulphur species of marine origin. By investigating the photoproducts within levitated droplets, we showed that elemental sulphur (α-S8) and sulphate (SO42-) can be photochemically generated at the gas-liquid interface by heterogeneous interaction with gaseous O2 and H2O. These results demonstrate that the surface of levitated droplets facilitate the oxidation of methyl thioglycolate in the dark, while illumination is necessary to produce the oxidation in bulk experiments.
- Seng, Samantha,Picone, A. Lorena,Bava, Yanina B.,Juncal, Luciana C.,Moreau, Myriam,Ciuraru, Raluca,George, Christian,Romano, Rosana M.,Sobanska, Sophie,Tobon, Yeny A.
-
-
Read Online
- α-Sulfur as a metal-free catalyst to activate peroxymonosulfate under visible light irradiation for decolorization
-
While transition metals have been frequently used to activate peroxymonosulfate (PMS) for chemical oxidation reactions, recently metal-free activation of PMS has also drawn great attention considering that no metal is required and the environmental impact can be minimized. In this study, orthorhombic α-sulfur (α-S), for the first time, is employed as a metal-free photocatalyst to activate PMS under visible (vis) light irradiation. To study the activation of PMS by the α-S/vis process, decolorization of rhodamine B (RhB) dye is selected as a model reaction. Parameters affecting the decolorization were investigated, including α-S loading, PMS dosage, temperature, pH, salt and inhibitors. The decolorization using PMS activated by α-S/vis was much faster than the self-activation of PMS. A higher α-S loading also facilitated the activation of PMS; however, over-loading of α-S led to the shielding effect, thereby decreasing the decolorization extent. Higher PMS dosages and temperatures were both preferable for the decolorization. While the decolorization was improved under acidic conditions, the activation of PMS was hindered under alkaline conditions. When high concentrations of NaCl were added to RhB solutions, the decolorization extent still remained almost the same. Electron paramagnetic resonance (EPR) spectroscopic analysis was performed to probe into the mechanism of PMS activated by the α-S/vis process. The α-S/vis process was found to be recyclable and stable over multiple cycles, even though α-S did not undergo any regeneration treatments. Considering these features, the α-S/vis process appears to be a promising and environmentally friendly process to activate PMS for chemical oxidation reactions.
- Andrew Lin, Kun-Yi,Zhang, Zhi-Yu
-
-
Read Online
- Sulfite-Promoted C-H Fluoroalkyl Sulfuration of Imidazoheterocycles with Bromofluoroacetate and Elemental Sulfur
-
A transition-metal-free sulfite-promoted three-component C-H sulfuration between imidazoheterocycles, elemental sulfur, and bromofluoroacetate is developed. Sulfites, including Na 2S 2O 4, NaHSO 3, and Na 2S 2O 3, are able to promote the formation of two C-S bonds in one step using elemental sulfur as a green sulfurating agent, allowing the rapid introduction of the synthetically useful S-fluoroacetate group into imidazoheterocycles. These new imidazoheterocycle derivatives bearing an S-fluoroacetate group can be easily modified to produce pharmaceutically attractive compounds.
- Gao, Yong-Chao,Huang, Zi-Hao,Zhang, Zhao-Sheng,Xie, Jin-Xin,Cui, Zi-Ning,Tang, Ri-Yuan
-
-
Read Online
- Ring transformations of 2-hydroxy-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)arenes
-
Abstract The cyclisation reactions of 2-(4-chloro-5H-1,2,3-dithiazol-5-ylidene-amino)phenol (5a), 3-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)pyridin-2-ol (5b) and 2-(4-chloro-5H-1,2,3-dithiazol-5-ylideneamino)pyridin-3-ol (5c) are investigated. Thermolysis in hot PhCl (132 °C) or under solvent free conditions at ca. 200 °C gave benzo[d]oxazole-2-carbonitrile (4a), oxazolo[5,4-b]pyridine-2-carbonitrile (4b) and oxazolo[4,5-b]pyridine-2-carbonitrile (4c) in high yields, while treatment with either NaH in dry THF at 66 °C or with i-Pr2NEt in DCM at 20 °C gave benzo[b][1,2,3]dithiazolo[5,4-e][1,4]oxazine (6a), [1,2,3]dithiazolo[5,4-e]pyrido[2,3-b][1,4]oxazine (6b) and oxazolo[4,5-b]pyridine (4c), respectively. The transformation of benzoxazine 6a and the pyridoxazine 6b into the corresponding oxazoles 4a and 4b was also investigated, and tentative mechanistic pathways for these transformations are proposed.
- Kalogirou, Andreas S.,Michaelidou, Sophia S.,Koyioni, Maria,Koutentis, Panayiotis A.
-
-
Read Online
- The Pyrolysis of Heptathiazocine
-
Heptathiazocine was pyrolyzed into ammonia, tetrasulfur tetranitride, and tetrasulfur dinitride above 383 K in an argon atmosphere; then, the latter two intermediates finally degraded into sulfur and nitrogen.According to the stoichiometric correlation am
- Kudo, Yoshiyuki,Hamada, Shuichi
-
-
Read Online
- Cleavage of SO2 on (η5-C5Me5)2Mo2(μ-S2)(μ-S)2 To form S8 and a Thiosulfate Complex, (η5-C5Me5)2Mo2(μ-S2)(μ-S)(μ-SSO3). Possible Role in Homogeneous Hydrogenation of SO2 Catalyzed by Mo-S Complexes
-
Reaction of SO2 with solutions of Cp*2Mo2(μ-S2)(μ-S)2 (1) initially yields 1*SO2, which is shown by crystallography to contain an SO2 weakly bound to a μ-S (S-S = 2.60 Angstroem).SO2 further reacts with 1*SO2 to quantitatively give Cp*2Mo2(μ-S2)(μ-S)(μ-SSO3) (2), which now contains an SO3 bound to the μ-S (S-S = 2.17 Angstroem).Effectively, a μ-S2O3 (thiosulfate) ligand is formed by an oxygen-transfer process, and the source of the oxygen as established by (18)O labeling is SO2.S8 is also produced, showing that SO2 has undergone net disproportionationto SO3 and S8.The raction rate is highly dependent on solvent polarity and base promoters such as Et3N.Sterically hindered amines do not accelerate the reaction, suggesting that they function as Lewis rather than Broensted bases.The X-ray structure of 2 is identical with that of a complex formed in low yield (along with dimeric oxosulfido complexes) by air oxidation of 1. 2 is readily hydrogenated at 25-75 deg C to regenerate 1, indicating that the mechanism of the previously studied hydrogenation of SO2 to S8 and H2O catalyzed by Mo-S complexes may involve 2 as an intermediate.Weak bases, e.g., Et3N, strip off the SO3 functionality in 2 to give primarily mixtures of isomers of 1 and products of base-SO3 interaction.Crystallographic data for Cp*2Mo2(μ-S2)(μ-S)(μ-S*SO2): space group P21/c; a = 13.738 (2) Angstroem, b = 10.581 (3) Angstroem, c = 17.331 (4) Angstroem, β = 92.41 (2)0; V = 2516.9 Angstroem3 at 296 K; Dcalc = 1.73 g/cm-1 for Z = 4; R = 6.2percent for 2017 independent reflections with I >/= 2?(I) and 2θ 0.Crystallogrphic data for Cp*2Mo2(μ-S2)(μ-S)(μ-SSO3): space group P21/c; a = 13.730 (5) Angstroem, b = 10.635 (3) Angstroem, c = 16.862 (2) Angstroem, β = 93.17 (5)0; V = 2458.5 Angstroem3 at 296 K; Dcalc = 1.81 g/cm-1 for Z = 4; R = 4.0percent for 2612 reflections with I >/= 2?(I) and 2θ 0.
- Kubas, Gregory J.,Ryan, Robert R.,Kubat-Martin, Kimberly A.
-
-
Read Online
- Growth and activation of an amorphous molybdenum sulfide hydrogen evolving catalyst
-
Amorphous molybdenum sulfide films, prepared by electrodeposition, are a class of highly active catalysts for hydrogen evolution. The growth mechanism of the films and the true active species were unclear. Herein, we report a study of the growth and activation of these films using Electrochemical Quartz Crystal Microbalance (EQCM) and X-ray photoelectron spectroscopy (XPS). Three processes, including oxidative deposition, reductive corrosion, and reductive deposition, are occurring during the growth of a molybdenum sulfide film. Deposition method, precursor concentration, and potential window are among the factors influencing the film growth. Regardless of deposition methods, all films exhibit similar catalytic activity on a per mass base. Potentiostatic oxidation (anodic electrolysis) is the method for fastest film growth; it produces a MoS3 film precatalyst which can be electrochemically activated. The activity of the MoS3 precatalyst scales with catalyst loading; at a loading of 0.2 mg/cm2, the current density is 20 mA/cm2 at an overpotential of 170 mV. Films differently deposited have different initial compositions, but the active catalysts in all films are the same MoS 2+x species, whose XPS characteristics are distinct from those of crystalline MoS2. The activation process of a MoS3 film precatalyst involves a reductive removal of slightly less than one equivalent of sulfide to form MoS2+x.
- Vrubel, Heron,Hu, Xile
-
-
Read Online
- Facile Construction of Yttrium Pentasulfides from Yttrium Alkyl Precursors: Synthesis, Mechanism, and Reactivity
-
Treatment of the yttrium dialkyl complex TpMe2Y(CH2Ph)2(THF) (TpMe2 = tri(3,5 dimethylpyrazolyl)borate, THF = tetrahydrofuran) with S8 in a 1:1 molar ratio in THF at room temperature afforded a yttrium pentasulfide TpMe2Y(κ4-S5) (THF) (1) in 93% yield. The yttrium monoalkyl complex TpMe2CpYCH2Ph(THF) reacted with S8 in a 1:0.5 molar ratio under the same conditions to give another yttrium pentasulfide [(TpMe2)2Y]+[Cp2Y(κ4-S5)]? (10) in low yield. Further investigations indicated that the S52- anion facilely turned into the corresponding thioethers or organic disulfides, and released the redundant S8, when it reacted with some electrophilic reagents. The mechanism for the formation of the S52- ligand has been investigated by the controlling of the reaction stoichiometric ratios and the stepwise reactions.
- Zhang, Fangjun,Zhang, Jie,Zhou, Xigeng
-
-
Read Online
- Basic reaction steps in the sulfidation of crystalline tungsten oxides
-
Hydrotreating is concerned with reactions for the removal of sulfur, nitrogen, oxygen, and heavy metals from crude oil. Sulfides of molybdenum or tungsten with cobalt or nickel supported on γ-Al2O3 constitute the catalytically active
- Weber,Kishan,Van der Vlies,Niemantsverdriet,Prins
-
-
Read Online
- Efficient reduction of sulfur dioxide with hydrogen over TiO2-supported catalysts derived from ruthenium salts and ruthenium cluster complexes
-
Catalytic reduction of SO2 to elemental sulfur was carried out over supported ruthenium catalysts that were derived not only from hexaruthenium carbonyl cluster complexes but also from RuCl3 as the precursor. The activity was largely dependent on the kind of metal oxide support used. Compared to the known systems, the TiO2-supported ruthenium catalysts operated with higher efficiency at lower temperature. Moreover, the selectivity was totally to elemental sulfur, forming no detectable amount of unfavorable H2S. H2S-free catalysis appeared to be a common feature of ruthenium catalysts regardless of the kind of precursors. The TiO2-supported catalyst derived from [N(PPh3)2]2[Ru6C(CO) 16] was much more active within the 463-508 K temperature region than the catalyst conventionally prepared from RuCl3, while both showed similar activity at more elevated temperatures. The kind of cation in anionic cluster complexes and the presence of an interstitial atom are important factors in generating supported catalysts that operate under mild conditions.
- Ishiguro, Atsushi,Liu, Yu,Nakajima, Takayuki,Wakatsuki, Yasuo
-
-
Read Online
- Catalytic conversion of COS and CS2 under an excess of sulfur dioxide
-
Conversion of organosulfur components (COS and CS2) in catalytic processing of a real reduced sulfurous gas was experimentally studied.
- Platonov,Tsemekhman
-
-
Read Online
- Complexes of Copper(I) with Dimercapto Compounds as Catalysts for Oxidation of Mercaptans and Hydrogen Sulfide with Molecular Oxygen in Aqueous Solutions
-
The conditions for formation of complexes of copper(I) with mercapto compounds in aqueousalkaline solutions and the catalytic activity of these complexes in oxidation of mercaptans and hydrogen sulfide was studied. The kinetic characteristics of these catalysts were compared with those of catalysts based on cobalt phthalocyanines. A method was proposed for suppressing formation of the thiosulfate ion in oxidation of H2S to elemental sulfur.
- Bagiyan,Koroleva,Soroka,Ufimtsev
-
-
Read Online
- Solution preparation of the amorphous molybdenum oxysulfide MoOS 2 and its use for catalysis
-
Acid condensation of aqueous MoO2S22- anion yields amorphous MoOS2 oxysulfide. This compound possesses tubular morphology and when freshly precipitated is soluble in polar organics such as acetone and ethanol. The ensemble of characterizations (IR, UV-visible, EXAFS spectroscopy) suggests that it contains cyclic or short linear oligomers of neutral molybdenum (V) oxysulfide MoOS2 core. Thermal decomposition of MoOS2 under inert atmosphere leads to the formation of a mixture of MoO2 and MoS2 phases. Promotion of MoOS2 with cobalt followed by sulfidation leads to highly active HDS catalysts.
- Genuit, Daisy,Bezverkhyy, Igor,Afanasiev, Pavel
-
-
Read Online
- Partial oxidation of H2S to sulfur on V-Cu-O mixed oxides bronzes
-
The present paper shows the influence of Cu-content in Cu-promoted V2O5 catalysts on both the physicochemical characteristics of catalysts and their catalytic performance in the partial oxidation of hydrogen sulfide. Both, the catalytic activity for H2S conversion and the selectivity to sulfur increased when increasing the Cu/V ratio of catalysts. The best catalyst gives a selectivity to sulfur at ca. 98% at total conversion of H2S. According to the characterization results (XRD, FTIR), V2O5 is partially transformed into vanadium oxide bronze, i.e. β-Cu0.261V2O5, up to Cu/V ratios of 0.25. For higher Cu/V ratios, CuV2O6 and β-Cu0.261V2O5 are observed. In the same way, the reducibility of V-species increased when increasing the Cu/V ratio of catalysts. On the other hand, the characterization of used catalysts indicates the transformation of V2O5 into V4O9, whereas the vanadium oxide bronze is stable under the studied reaction. The catalytic results are explained on the basis of the nature of crystalline phases and the presence of V5+-O-V4+ pairs in the more selective catalysts.
- Ruiz-Rodríguez, Lidia,Blasco, Teresa,Rodríguez-Castellón, Enrique,Nieto, José M. López
-
-
Read Online
- The preparation of 1, 5-Se2S2N4
-
The reaction of [(Me3Si)2N]2S with an equimolar amount of SeCl4 or the reaction of [(Me3Si)2N]2Se with 1:1 mixture of SCl2 and SO2Cl2 produces 1,
- Maaninen, Arto,Siivari, Jari,Laitinen, Risto S.,Chivers, Tristram
-
-
Read Online
- Photoinduced nucleation of carbon disulfide
-
The action of light on undersaturated and supersaturated vapors of carbon disulfide has been investigated using a batch photochemical reactor and a thermal diffusion cloud chamber, respectively.Photoinduced nucleation was observed in each case.In the batch reactor enough sulfur was produced to nucleate and grow a sulfur aerosol.A model for the photoinduced nucleation of supersaturated carbon disulfide is proposed based upon the photochemical production and subsequent nucleation of sulfur.The model predictions compare well with observed nucleation delay time and nucleation rate data.A variation of the model utilizing diradical polymerization instead of nucleation is used to explain photoinduced nucleation results in the literature involving dilute solutions of carbon disulfide in supersaturated ethanol vapor.
- Kalisky, Ofra,Heist, Richard H.
-
-
Read Online
- Novel non-aqueous Fe(III)/Fe(II) redox couple for the catalytic oxidation of hydrogen sulfide to sulfur by air
-
A series of Fe(iii) salts and organic solvents have been screened to develop novel non-aqueous catalysts for the conversion of H2S to sulfur. FeCl3/95% N-methylpyrrolidinone/5% H2O was found to be a most efficient non-aqueous system. The process chemistry, the proposed mechanism of catalytic oxidation of H2S, and the electrochemistry are discussed. The Royal Society of Chemistry 2006.
- Hua, Guoxiong,Zhang, Qingzhi,McManus, Derek,Slawin, Alexandra M. Z.,Woollins, J. Derek
-
-
Read Online
- Gas-phase and matrix-isolation photochemistry of methyl thioglycolate, CH3OC(O)CH2SH: Influence of the presence of molecular oxygen in the photochemical mechanisms
-
The photochemistry of methyl thioglycolate (MTG), CH3OC(O)CH2SH, in gas phase and in matrix isolation conditions was studied by means of FTIR spectroscopy, and the influence of the presence of molecular oxygen on the photochemical me
- Bava, Yanina B.,Tamone, Luciana M.,Juncal, Luciana C.,Seng, Samantha,Tobón, Yeny A.,Sobanska, Sophie,Picone, A. Lorena,Romano, Rosana M.
-
-
Read Online
- Unexpected formation of ammonium thiocyanate from the reaction of aqueous hydroxylamine with carbon disulfide
-
Reaction of aqueous hydroxylamine with carbon disulfide in acetonitrile or in tetrahydrofuron unprecedentedly results in the formation of ammonium thiocyanate and sulfur.
- Rao, Muddamarri Hanumantha,Pallepogu, Raghavaiah,Muralidharan, Krishnamurthi
-
-
Read Online
- Molecular dissociation and two low-temperature high-pressure phases of H2S
-
We performed powder x-ray experiments on hydrogen sulfide (H2S) under high pressure at room and low temperatures. Phase V appearing above 27 GPa at room temperature was confirmed by x ray to be associated with a molecular dissociation. The molecular dissociation was first observed at 150 K at a higher pressure around 43 GPa. Two new low-temperature high-pressure phases III′ and IV′ were discovered. Spiral chains of sulfur atoms are found in both phases as well as in phase IV.
- Fujihisa, Hiroshi,Yamawaki, Hiroshi,Sakashita, Mami,Nakayama, Atsuko,Yamada, Takahiro,Aoki, Katsutoshi
-
p. 214102-1-214102-5
(2004)
-
Read Online
- Twelve-connected net with face-centered cubic topology: A coordination polymer based on [Cu12(μ4-SCH3) 6]6+ clusters and CN- linkers
-
(Chemical Equation Presented) Globular configuration: a microporous coordination polymer based on a dodecanuclear copper(I) cluster (picture: C black, Cu red, N blue, S yellow) as a twelve-connected node, was synthesized by a simultaneous redox, sulfurization, and self-assembly reaction under solvothermal conditions. The synthesis provides a model reaction to simulate the transformation of inorganic sulfur into organic sulfur.
- Li, Dan,Wu, Tao,Zhou, Xiao-Ping,Zhou, Rui,Huang, Xiao-Chun
-
-
Read Online
- Nickel sulfides decorated sic foam for the low temperature conversion of H2S into elemental sulfur
-
The selective oxidation of H2S to elemental sulfur was carried out on a NiS2/SiCfoam catalyst under reaction temperatures between 40 and 80 ?C using highly H2S enriched effluents (from 0.5 to 1 vol.%). The amphiphilic properties of SiC foam provide an ideal support for the anchoring and growth of a NiS2 active phase. The NiS2/SiC composite was employed for the desulfurization of highly H2S-rich effluents under discontinuous mode with almost complete H2S conversion (nearly 100% for 0.5 and 1 vol.% of H2S) and sulfur selectivity (from 99.6 to 96.0% at 40 and 80 ?C, respectively), together with an unprecedented sulfur-storage capacity. Solid sulfur was produced in large aggregates at the outer catalyst surface and relatively high H2S conversion was maintained until sulfur deposits reached 140 wt.% of the starting catalyst weight. Notably, the spent NiS2/SiCfoam catalyst fully recovered its pristine performance (H2S conversion, selectivity and sulfur-storage capacity) upon regeneration at 320 ?C under He, and thus, it is destined to become a benchmark desulfurization system for operating in discontinuous mode.
- Duong-Viet, Cuong,Nguyen-Dinh, Lam,Liu, Yuefeng,Tuci, Giulia,Giambastiani, Giuliano,Pham-Huu, Cuong
-
-
Read Online
- BIOMIMETIC REDUCTION OF SULFURIC ACID.
-
Sulfuric acid and sodium sulfate were readily reduced to elemental sulfur and hydrogen sulfide upon treatment with a mixture of either one of polyphosphoric acid derivatives, PPE, PPA, and P//4O//1//0, which can form a mixed anhydride having -P-O-S- linkage, and iodide or thiol. Sulfur dioxide, which is undoubtedly one of the important intermediates, was trapped by p-tolyllithium to afford p-toluenesulfinic acid which was converted to p-tolyl methyl sulfone upon treatment with methyl iodide, though the yield was low. Sulfur trioxide which has been postulated as the key intermediate in the biological reduction of inorganic sulfate, was also trapped by mesitylene to give mesitylenesulfonic acid in a high yield. The reduction of sulfate to elemental sulfur and hydrogen suylfide is considered to proceed through the course which resembles the biological reaction path involved in the assimilatory metabolism of inorganic sulfate in microorganisms and plants.
- Oae,Togo
-
-
Read Online
- Building complex two-dimensional structures: Methylene blue on self-assembled monolayer-covered Au(111)
-
The charge transfer of methylene blue molecules immobilized on different monolayer covered-Au(111) surfaces has been studied by electrochemical techniques complemented by scanning tunneling microscopy. The positively charged methylene blue ions (MB+) are effectively immobilized on negatively charged S and I adlayers. The amount of charge related to the (MB+/MBH) surface redox couple (qsurf) depends on the surface concentration of the adsorbed S and I atoms and on their geometric arrangement. When methylene blue immobilization is made on COO--terminated thiols (mercaptopropionic acid, MPA, and mercaptoundecanoic acid, MUA), the value of qsurf is markedly reduced, indicating that the electron transfer through hydrocarbon chains is very difficult, although the MB+ is effectively immobilized. Sulfide contamination introduces defects in the MPA and MUA layers and, thus, markedly increases the number of immobilized methylene blue molecules that are active for charge transfer. Electrochemical runs made with methylene blue in solution demonstrate that defects are the main path for electron transfer through COO--terminated thiol-covered Au(111) surfaces. For lowdefect COO--terminated thiol adlayers, a diode-like effect related to the blocking of the anion-transport through small pores with negatively charged gates is observed.
- Vericat,Lenicov, F. Remes,Tanco,Andreasen,Vela,Salvarezza
-
-
Read Online
- Hollow sulfur@graphene oxide core-shell composite for high-performance Li-S batteries
-
In this paper, a hollow sulfur@graphene oxide core-shell composite is synthesized for high-performance lithium-sulfur batteries through a facile two-step solution method with the assistance of polyvinylpyrrolidone. Scanning electron microscope observation shows that the hollow sulfur sphere is coated by the homogeneous graphene oxide nanolayer, and thermogravimetric analysis demonstrates the composite holds sulfur loading as high as 92 wt%. The composite served as cathode in lithium-sulfur batteries shows its capacity as high as 745 mAh g-1 at 0.2C after 20 cycles. It also has an excellent cycling stability even at a high current density of 1C (73% retention and 96% coulombic efficiency after 150 cycles), implying that the diffusion of the polysulfides into electrolyte can be greatly inhibited. It is believed that the structure design of graphene oxide coated hollow sulfur sphere can be developed for the practical application of high-performance lithium-sulfur batteries.
- Zhang, Jiawei,Yang, Ning,Yang, Xiaogang,Li, Shengji,Yao, Juming,Cai, Yurong
-
-
Read Online
- Dynamic combinatorial chemistry in a solvothermal process of Cu(i,ii) and organosulfur ligands
-
An unprecedented microwave C(sp2)-S and S-S bond activation of 2,2′-dipyridyldisulfide (2-dpds) and the formation of a new architecture of coordination networks obtained by reaction of Cu(HCO2) 2·xH2O with 2-dpds under solvothermal microwave conditions are reported. This unusual reaction proceeds with the partial oxidation of 2,2′-dipyridyldisulfide to sulfate. The process generates: a Cu(i) dimetallic complex [Cu2(μ-Hpyt)2(Hpyt) 4](SO4)·~5EtOH (1), a Cu(i,ii) polycationic coordination polymer [Cu(H2O)6][Cu6(μ-Hpyt) 12](SO4)4·4H2O (2) and a dimetallic Cu(ii) complex [Cu(2-dps)(μ-SO4)(H2O)] 2·3H2O (3). It is worth mentioning the strong red luminescence shown by compounds 1 and 2. The Royal Society of Chemistry 2010.
- Delgado, Salome,Santana, Adriano,Castillo, Oscar,Zamora, Felix
-
-
Read Online
- Reaction of Nitroxyl (HNO) with Hydrogen Sulfide and Hydropersulfides
-
Nitroxyl (HNO) has gained a considerable amount of attention because of its promising pharmacological effects. The biochemical mechanisms of HNO activity are associated with the modification of regulatory thiol proteins. Recently, several studies have suggested that hydropersulfides (RSSH), presumed signaling products of hydrogen sulfide (H2S)-mediated thiol (RSH) modification, are additional potential targets of HNO. However, the interaction of HNO with reactive sulfur species beyond thiols remains relatively unexplored. Herein, we present characterization of HNO reactivity with H2S and RSSH. The reaction of H2S with HNO leads to the formation of hydrogen polysulfides and sulfur (S8), suggesting a potential role in sulfane sulfur homeostasis. Furthermore, we show that hydropersulfides are more efficient traps for HNO than their thiol counterparts. The reaction of HNO with RSSH at varied stoichiometries has been examined with the observed production of various dialkylpolysulfides (RSSnSR) and other nitrogen-containing dialkylpolysulfide species (RSS-NH-SnR). We do not observe evidence of sulfenylsulfinamide (RS-S(O)-NH2) formation, a pathway expected by analogy with the known reactivity of HNO with thiol.
- Zarenkiewicz, Jessica,Khodade, Vinayak S.,Toscano, John P.
-
p. 868 - 877
(2021/01/14)
-
- PROCESSES USEFUL IN THE MANUFACTURE OF CYCLODODECASULFUR
-
Methods for producing cyclododecasulfur are disclosed that include the steps of: reacting a bromide with molecular chlorine to obtain molecular bromine and a chloride; oxidizing the chloride in aqueous solution with removal of electrons to obtain molecular chlorine; reducing water with electrons to obtain hydrogen and a hydroxide; and reacting a metallasulfur derivative with the molecular bromine, to produce cyclododecasulfur and a metallabromide derivative.
- -
-
Paragraph 00280
(2020/09/30)
-
- Nitrosonium reactivity of (NHC)Copper(I) sulfide complexes
-
This study examines the reactivity of a series of copper(I) sulfide complexes stabilized by the expanded-ring N-heterocyclic carbene (NHC) 1,3-bis(2,6-diisopropylphenyl)-4,5,6,7-tetrahydro-1,3-diazepin-2-ylidene (7Dipp) toward the nitrosonium ion (NO+). 7Dipp is shown to support neutral sulfide- and disulfide-bridged dicopper(I) complexes, as well as mononuclear copper(I) hydrosulfide. The addition of NO+ to each of these results in the formation of NHC-supported copper(I) cations and elemental sulfur. Reduction of copper(I) to copper(0) is observed upon reaction of NO+ with dicopper(I) sulfide or disulfide, whereas ammonium ion formation is observed upon reaction of copper(I) hydrosulfide with NO+. Ammonium ion formation is likewise observed upon reaction of NO+ with (7Dipp)copper(I) hydride.
- Jordan, Abraham J.,Walde, Rebecca K.,Schultz, Kelly M.,Bacsa, John,Sadighi, Joseph P.
-
supporting information
p. 9592 - 9596
(2019/08/22)
-
- Tin guanidinato complexes: Oxidative control of Sn, SnS, SnSe and SnTe thin film deposition
-
A family of tin(ii) guanidinate complexes of the general form [{RNC(NMe2)NR}2Sn] (R = iPr (6), Cy (7), Tol (9) and Dipp (10)) and [{tBuNC(NMe2)NtBu}Sn{NMe2}] (8) have been synthesised and isolated from the reaction of tin(ii) bis-dimethylamide and a series of carbodiimides (1-5). The cyclic poly-chalcogenide compounds [{CyNC(NMe2)NCy}2Sn{Chx}] (Ch = S, x = 4 (11); Ch = Se, x = 4 (12), and Ch = S, x = 6 (13)) with {SnChx} rings were prepared by the oxidative addition of elemental sulfur and selenium to the heteroleptic stannylene complex [{CyNC(NMe2)NCy}2Sn] (7) in THF at room temperature. Similarly, reaction of compounds 6 and 7 with an equimolar amount of the chalcogen transfer reagents (SC3H6 and SePEt3, respectively) led to the formation of the chalcogenide tin(iv) complexes [{RNC(NMe2)NR}Sn(Ch)] (R = Cy: Ch = S (14); R = iPr, Ch = Se (15); R = Cy, Ch = Se (16)) with terminal SnCh (14 and 16) and dimeric bridged seleno-tin {Sn2Se2} rings (15), respectively. The mono telluro-compounds [{RNC(NMe2)NR}Sn(Te)] (R = iPr (17); R = Cy (18)) were similarly prepared by the oxidative addition of elemental tellurium to 7 and 8, respectively. All of the tin containing compounds have been investigated by multinuclear NMR (1H, 13C 119Sn and 77Se/125Te, where possible), elemental analysis and single crystal X-ray structural analysis (7, 8, 10-13, 15-18). Thermogravimetric analysis (TGA) was used to probe the possible utility of complexes 6-8, 11-12 and 14-18 as single source Sn and SnCh precursors. The Sn(ii) compounds 6 and 7 have been utilised in the growth of thin films by aerosol-assisted chemical vapor deposition (AACVD) at both 300 and 400 °C. The thin films have been analysed by pXRD, EDS, SEM and AFM and shown to be Sn metal. Subsequent studies provided film growth at temperatures as low as 200 °C. Similarly, the mono-chalcogenide systems 14, 16 and 18 have been utilised in the AACVD of thin films. These latter studies provided films, grown at 300 and 400 °C, which have also been analysed by pXRD, Raman spectroscopy, AFM, and SEM and are shown to comprise phase pure SnS, SnSe and SnTe, respectively. These preliminary results demonstrate the potential of such simple guanidinate complexes to act as single source precursors with a high degree of oxidative control over the deposited thin films.
- Ahmet, Ibrahim Y.,Hill, Michael S.,Raithby, Paul R.,Johnson, Andrew L.
-
p. 5031 - 5048
(2018/04/10)
-
- Understanding hydrogen sulfide storage: Probing conditions for sulfide release from hydrodisulfides
-
Hydrogen sulfide (H2S) is an important biological signaling agent that exerts action on numerous (patho)physiological processes. Once generated, H2S can be oxidized to generate reductant-labile sulfane sulfur pools, which include hydrodisulfides/persulfides. Despite the importance of hydrodisulfides in H2S storage and signaling, little is known about the physical properties or chemical reactivity of these compounds. We report here the synthesis, isolation, and characterization (NMR, IR, Raman, HRMS, X-ray) of a small-molecule hydrodisulfide and highlight its reactivity with reductants, nucleophiles, electrophiles, acids, and bases. Our experimental results establish that hydrodisulfides release H2S upon reduction and that deprotonation results in disproportionation to the parent thiol and S0, thus providing a mechanism for transsulfuration in the sulfane sulfur pool.
- Bailey, T. Spencer,Zakharov, Lev N.,Pluth, Michael D.
-
supporting information
p. 10573 - 10576
(2014/08/18)
-
- Reactivity of the bridged-sulfide complex Pd2Cl 2(μ-S)(μ-dmpm)2 toward electrophiles
-
The dipalladium(i) complex Pd2Cl2(dmpm)2 (1a) [dmpm = bis(dimethylphosphino)methane] is known to react with elemental sulfur (S8) to give the bridged-sulfide complex Pd2Cl 2(μ-S)(dmpm)2 (2a) but, in the presence of excess S8, PdCl2[P,S-dmpm(S)] (4a) and dmpm(S)2 are generated. Treatment of 1a with elemental selenium (Se8), however, gives only Pd2Cl2(μ-Se)(dmpm)2 (3a). Complex 4a is best made by reaction of trans-PdCl2(PhCN)2 with dmpm(S). Complex 2a reacts with MeI to yield initially Pd2I 2(μ-S)(dmpm)2 and MeCl, and then Pd2I 2(μ-I)2(dmpm)2 and Me2S, whereas alkylation of 2a with MeOTf generates the cationic, bridged-methanethiolato complex [Pd2Cl2(μ-SMe)(dmpm)2]OTf (5). Oxidation of 2a with m-CPBA forms a mixture of Pd2Cl 2(μ-SO)(dmpm)2 and Pd2Cl2(μ- SO2)(dmpm)2, whereas Pd2Br2(μ-S) (dmpm)2 reacts selectively to give Pd2Br 2(μ-SO)(dmpm)2 (6b). Treatment of the Pd 2X2(μ-S)(dmpm)2 complexes with X2 (X = halogen) removes the bridged-sulfide as S8, with co-production of PdII(dmpm)-halide species. X-ray structures of 3a, 5 and 6b are presented. Reactions of dmpm with S8 and Se8 are clarified. Differences in the chemistry of the dmpm systems with that of the corresponding dppm systems [dppm = bis(diphenylphosphino)methane] are discussed.
- Pamplin, Craig B.,Rettig, Steven J.,Patrick, Brian O.,James, Brian R.
-
p. 1991 - 2002
(2012/03/27)
-
- Photocatalytic splitting of CS2 to S8 and a carbon-sulfur polymer catalyzed by a bimetallic ruthenium(II) compound with a tertiary amine binding site: Toward photocatalytic splitting of CO2?
-
The catalytic photocleavage of CS2 to S8 and a (CxSy)n polymer with visible light using a dinuclear ruthenium(II) compound with a bipyridine units for photoactivity and a vicinal tertiary amine binding site for CS2 activation was studied. The catalyst was characterized by X-ray diffraction, 1H NMR, and 13C NMR, ESI-MS and elemental analysis. CS2 photocleavage was significant (240 turnovers, 20 h) to yield isolable S8 and a (CxSy)n polymer. A mononuclear catalyst or one without an amine binding site showed significantly less activity. XPS of the (CxSy)n polymer showed a carbon/sulfur ratio ~1.5-1.6 indicating that in part both C-S bonds of CS2 had been cleaved. Catalyst was also included within the polymer. The absence of peaks in the 1H NMR verified the (CxSy)n nature of the polymer, while 13C NMR and IR indicated that the polymer had multiple types of C-S and C-C bonds.
- Livanov, Konstantin,Madhu, Vedichi,Balaraman, Ekambaram,Shimon, Linda J. W.,Diskin-Posner, Yael,Neumann, Ronny
-
p. 11273 - 11275
(2012/01/04)
-
- Unexpected multiple bond cleavage and rearrangement of organosulfide ligands in the presence of Cu(ii) assisted by solvothermal and solvothermal-microwave conditions
-
An unprecedented in situ multiple bond cleavage of S-S, S-C(sp2) and C-N in the pyrimidinedisulfide (pym2S2) ligand is observed by the reaction of CuCl2·2H2O with this ligand under solvothermal and solvothermal-microwave conditions. In this process the formation of the compound [CuII(μ-Cl)(Cl)L]2, where L represents the new ligand (L = 2-(pyrimidin-2-ylamino)-1,3-thiazole-4- carbaldehyde), is observed. This ligand has been further isolated and X-ray characterized. The similar reaction carried out under solvothermal-microwave conditions gives, in addition to the latter compound, the complex {9·[Cu(pym2S3)(μ-Cl)(Cl)]2· [Cu(pym2S2)(μ-Cl)(Cl)]2}. Coordination of a pyrimidinetrisulfide ligand (pym2S3) is reported for the first time. This work represents an illustrative example of the novel synthetic perspectives attainable via solvothermal-microwave procedures. The Royal Society of Chemistry 2011.
- Delgado, Salome,Gallego, Almudena,Castillo, Oscar,Zamora, Felix
-
p. 847 - 852
(2011/04/15)
-
- Synthesis, structure, transformation studies and catalytic properties of open-framework cadmium thiosulfate compounds
-
Five new thiosulfate based inorganic-organic hybrid open-framework compounds have been synthesized employing mild reaction conditions. Of the five compounds, [Na2(H2O)8][Cd(C10H 8N2)(S2O3)2] ·2H2O, I and [Cd2(C10H8N 2)2(HS2O3)2(S 2O3)2][(C10H9N 2)2(C10H8N2) 2]·8H2O, II have one-dimensional (1D) structures and [Cd(C10H8N2)(H2O) 2(S2O3)]·2H2O, III, [Cd 2(C10H8N2)3(S 2O3)2], IV and [Cd2(C 10H8N2)2.5(S2O 3)2], V have three-dimensional (3D) structures. The 1D structures are somewhat related, formed by the bonding between tetrahedral Cd centers (CdN2S2) and 4,4′-bipyridine (bpy) units. The inter-chain spaces are occupied by the hanging thiosulfate units in both the cases along with Na(H2O)6 chains in I and free bpy units in II. The three 3D structures have one-dimensional cadmium thiosulfate chains linked by bpy units. Interpenetration has been observed in all the 3D structures. The 3D structures appear to be related and can be derived from fgs net. Transformation studies on the 1D compound, [Na2(H 2O)8][Cd(C10H8N2)(S 2O3)2]·2H2O, I, indicated a facile formation of [Cd(C10H8N2)(H 2O)2(S2O3)]·2H2O, III. Prolonged heating of I gave rise to a 3D cadmium sulfate phase, [Cd 2(C10H8N2)2(H 2O)3(SO4)2]·2H2O, VI. Compound VI has one-dimensional cadmium sulfate chains formed by six-membered rings connected by bpy units to form a 3D structure, which appears to resemble the topological arrangement of III. Transformation studies of III indicates the formation of IV and V, and at a higher temperature a new 3D cadmium sulfate, [Cd(C10H8N2)(SO4)], VII. Compound VII has a 4 × 4 grid cadmium sulfate layers pillared by bpy units. All the compounds were characterized by PXRD, TGA, IR and UV-visible studies. Preliminary studies on the possible use of the 3D compounds (III-VII) in heterogeneous cyanosilylation of imines appear to be promising. The Royal Society of Chemistry 2010.
- Paul, Avijit Kumar,Madras, Giridhar,Natarajan, Srinivasan
-
p. 2263 - 2279
(2010/06/14)
-
- Synthetic and electrochemical studies on 1,1′-dithia-substituted derivatives of ferrocene and structure of 1,3-dithia[3]ferrocenophane [Fe(C5H4S)2CH2]
-
The bimetallic complexes fc(μ2-S)2TiCp22 (1, fc = 1,1′-ferrpcenyl, Cp = cyclopentadienyl) and fc(μ2-S2)(μ2-S)TiCp2 (2) were synthesized by reaction of fc(SH)2 with Cp2TiCl2, and from fcS3 and Cp2Ti(CO)2, respectively. The novel tetrasulfane fcS4 was obtained from 2 and SCl2. 1,3-Dithia[3]ferrocenophane fcS2CH2 was obtained from fc(SH)2 and CH2Cl2 in the presence of Cp2TiCl2 and KOH. The molecular and crystal structure of fcS2CH2 was determined by X-ray crystallography; the molecular symmetry is Cs. Electrochemical studies on the recently prepared ferrocenophanes fcS2-1-SO, fcS2-1-SO2, and fcS2-2-SO show that, with respect to fcS3, the progressive oxidation of the trisulfane bridge makes more and more difficult the fc/fc+ oxidation, whereas insertion of a Cp2Ti fragment exerts the opposite effect.
- Steudel, Ralf,Hassenberg, Karin,Pickardt, Joachim,Grigiotti, Emanuela,Zanello, Piero
-
p. 2604 - 2608
(2008/10/08)
-
- Coordination of cyclo-octasulfur and cyclo-heptaselenium to dinuclear rhenium(I) systems
-
By substitution reactions of the coordinated THF ligands of Re2(μ-X)2(CO)6(THF)2 by elemental chalcogens (S8 and red selenium), the complexes Re2(μ-X)2(CO)6(S8) (X = Br, 1; 1, 2), and Re2(μ-X)2(CO)6(Se7), (X = I, 3; Br, 4) have been prepared. Binuclear compound 3 was crystallographically established to be a coordination compound of cyclo-heptaselenium, two adjacent selenium atoms of the Se7 ligand [Se-Se distance, 2.558(3) A] being bonded to rhenium(I), at an average Re-Se distance of 2.586(3) A, and the nonbonding ReRe distance being 4.077(3) A. Spectroscopic evidence of the existence of these chalcogen complexes in solution is reported. The Re2(μ-X)2(CO)6(S8) complexes undergo S8 displacement by THF, while the coordinated Se7 moiety is less readily displaced from 3.
- Bacchi, Alessia,Baratta, Walter,Calderazzo, Fausto,Marchetti, Fabio,Pelizzi, Giancarlo
-
p. 3894 - 3900
(2008/10/08)
-
- Crystal structures of monofluorosulfites MSO2F (M = K, Rb)
-
Single crystals of potassium and rubidium fluorosulfite were obtained for the first time by reacting the alkali metal fluorides with sulfur dioxide in acetonitrile at 75 °C. According to the results of X-ray structure determinations they are isotypic (monoclinic, P21/m, Z = 2, KSO2F: a = 696.2(2), b = 566.3(2), c = 465.8(1) pm, β = 107.73(2)o, RbSO2F: a = 717.2(1), b = 586.7(1), c = 484.0(1) pm, β = 107.14(1)o) and structurally analogous to potassium chlorate. In contrast to potassium fluoroselenite in which the complex anions are polymerized to linear chains by unsymmetric fluorine bridges, the fluorosulfite anion is isolated. The S-F-distance of 159.1(2) pm (KSO2F) corresponds to a S-F single bond, the S-O-distance of 152.6(2) pm indicates a bond order of 1.5.
- Kessler, Ulrich,Jansen, Martin
-
p. 385 - 388
(2008/10/08)
-
- Vibrational Spectra and Structural Aspects of Fluorosulfites
-
The Raman and infrared spectra of the fluorosulfites of K+, Rb+, Cs+, NH4+, and Me4N+ have been examined. Previous assignment of the fundamental vibrations is revised, and an ab initio study of the SO2F- anion is presented. For the pyramidal anion of symmetry Cs, distances of r(S-O) = 1.458 ? and r(S-F) = 1.698 ? have been calculated. The heat of formation of Me4NSO2F (-14.0 kcal/mol) was derived from the dissociation pressure of the salt. In addition, the lattice energy of Me4NF (159.2 kcal/mol) was calculated from a thermochemical cycle. The thermochemical data are discussed in terms of reactivity of the fluorides and stability of the fluorosulfites.
- Kornath, Andreas,Neumann, Frank,Ludwig, Ralf
-
p. 5570 - 5573
(2008/10/09)
-
- Novel titanocene thiolato complexes and their application in preparing new sulfur-containing heterocycles
-
Treatment of Cp2Ti(CO)2 (3) with the di- and polysulfanes 1,2,4-(CH2)2S3, C4S6 (9), C7H10S3 (11), 1,2,4,6-(CH2)3S4/su
- Steudel, Ralf,Kustos, Monika,Muenchow, Vera,Westphal, Ursula
-
p. 757 - 764
(2007/10/03)
-
- The Synthesis of Cyclic Organosulfur Compounds from (C5H4)4Ti2C2S4 by Ligand Transfer Reactions
-
The tetrathiaoxalate complex Cp4Ti2C2S4 (1) reacts with an equimolar amount of COCl2 to give the blue-green mononuclear complex Cp2TiC2S4CO (4).This reaction is analogous to the known reactions of 1 with SCl2 or S2Cl2.However, when 1 was treated with equimolar amounts of the bifunctional sulfenyl chlorides 1,2-C2H4(SCl)2 (5), 1,3-C3H6(SCl)2 (6) or 1,2-C6H4(SCl)2 (7), the bi- or monocyclic tetrakisdisulfanes C6H8S8 (9b), C8H12S8 (10), and C14H8S8 (11), respectively, were obtained.The X-ray crystal structure analysis of 11*CS2 showed that 11 possesses Ci symmetry with a central exocyclic CC double bond similar to tetrathiafulvalenes: C6H4(μ-S2)2C=C(μ-S2)2C6H4. - Key Words: Titanocene complexes/ Organosulfur ligands/ Ligand transfer/ Organosulfur heterocycles/ Sulfur-sulfur bonds
- Steudel, Ralf,Westphal, Ursula,Pickardt, Joachim
-
p. 561 - 564
(2007/10/02)
-
- Reaction of Diorganogallium(indium) Fluorides. The Crystal Structure of Mes2InF
-
Mes2GaF (1) reacts with t-BuNH2 at 20°C to the amine adduct [Mes2Ga(F)(t-BuNH2)] (2). Treatment of 1 with H2S gives after a redox reaction γ-S8-sulfur (Muthmanns' Sulfur) (3) as the only isolated product. When i-Pr2InF (4) is reacted with [SnCl2(dioxane)] in toluene at 70°C one yields after workup [i-PrInCl2(dioxane)] (5), which is formedafter ligand exchange and reaction with dioxane. 2 and 5 were investiga ted by NMR-, IR- and MS-techniques. In addition, 2*2.5THF, 3, 5 and Mes2InF were characterized by an X-ray structure determination. According tothat 2*2.5THF contains dimeres, associated by hydrogen bridges, while 5 possesses a polymeric structure with bridging dioxane molecules. 3 form s eightmembered rings with C2 symmetry. Mes2InF is a trimer in a solid state with an In3F3-backbone.
- Kraeuter, Thomas,Neumueller, Bernhard
-
-
- Disproportionation of SO2 to S8 and SO3 on Cp*2Cr2S5. Crystallographic and 34S-labeling evidence for an oxygen-transfer mechanism and observation of facile exchange of Cr2S5 core sulfurs with 34S. Structures of Cp*2Cr ...
-
Full title: Disproportionation of SO2 to S8 and SO3 on Cp*2Cr2S5. Crystallographic and 34S-labeling evidence for an oxygen-transfer mechanism and observation of facile exchange of Cr2S5 core sulfurs with 34S. Structures of Cp*2Cr2(μ-S)(μ-η2-S 2)(μ-η1-SS·SO2)·SO 2 and Cp*2Cr2(μ-S)(μ-η2-S 2)(μ-SSO3). The syntheses, structures, and reactivities of Cp*2Cr2(μ-S)(μ-S 2)(μ-SS·SO2)·SO 2,1·2SO2, and Cp*2Cr2(μ-S)(μ-S2)(μ-SSO 3)·(CD3OD)lattice, 2, are reported. Reversible addition of SO2 to Cp*2Cr2S5,1, to give 1·2SO2 was found to occur at room temperature. 1 possesses a novel μ-η1-S2 ligand, and X-ray crystallography of 1·2SO2 showed that SO2 binds as a Lewis acid to the terminal sulfur of this ligand with an acute S-S-S angle (94°). The S-SO2 distance of 2.41 A? is about 0.2 A? shorter than in the previously known Cp*2Mo2(μ-S)(μ-S 2)(μ-S·SO2). Consistent with this greater activation, 1·2SO2 further reacts in the presence of excess SO2 to give the thiosulfate 2 (isomorphous to the Mo analogue) at a much faster rate than in the Mo system. Significantly, the crystal structure of 1·2SO2 shows the presence of associated SO2 molecules unsymmetrically bridging (via sulfur) the oxygen atoms of each sulfide-bound SO2 molecule to give a cyclic aggregate of four SO2 molecules (intermolecular S?O distances of 2.78 and 2.95 A?). Infrared studies demonstrate that these interactions further activate (weaken) the S=O bonds of the sulfide-bound SO2. Thus, it is proposed that the mechanism of SO2 disproportionation in solution involves base-assisted oxygen atom transfer from the sulfide-bound SO2 molecule to the associated SO2 to produce SO3. The SO3 then displaces S2O (which decomposes to S8 and SO2) from the bridging sulfide ligand to give the observed thiosulfate product. The reactivities of 1·2SO2 and Cp*2Cr2S4·SO2 vs Cp*2Mo2S4·SO2 and of 2 vs Cp*2Mo2S4·SO3 are discussed. A mechanism for the oxygen atom transfer reaction is proposed on the basis of the crystal structure of 1·2SO2 and 34S-labeling studies. Facile reaction of Cp*2Cr2S4 with S8 was found to give 1, and all five of the core sulfurs in the latter incorporated 34S if excess 34S8 was used. 1·2SO2 and 2 crystallize in the space groups C2/c and P1, respectively. The cell dimensions are the following: 1·2SO2, a = 16.087 (4) A?, b = 15.926 (3) A?, c = 21.650 (3) A?, β = 105.29 (2)°, and Z = 8; 2, a = 10.336 (2) A?, b = 10.891 (2) A?, c = 13.219 (3) A?, α = 85.15 (3)°, β = 78.85 (3)°, γ = 62.39 (3)°, and Z = 2. R = 4.85% for 1·2SO2, and R = 4.84% for 2.
- Toupadakis, Andreas,Kubas, Gregory J.,Burns, Carol J.
-
p. 3810 - 3817
(2008/10/08)
-
- Selenium sulfur dihalides, ChnX2 (n = 1, 2, 3; Ch = Se, S; X = Br, Cl). Raman and 77Se NMR spectroscopic characterization
-
Solutions of Se2Cl2 in S2Cl2, Se2Br2 in S2Cl2, Se in S2Cl2, and S in Se2Cl2 have been studied by Raman and 77Se NMR spectroscopy.Selenium sulfur dihalides, SeSCl2, SeSBr2, and SeSBrCl, formed in these solutions, have been shown by Raman and 77Se NMR spectroscopy to have chain structures.Solutions of Se2Cl2 in S2Cl2, S in Se2Cl2, and Se in S2Cl2 have been shown to contain, in addition to Se2Cl2, S2Cl2, SeSCl2, Se3Cl2, and S8, trichalcogen dichlorides Se2SCl2 and SeS2Cl2.Selenium-77 signals corresponding to all seven chain isomers of the expected Se-containing dichalcogen dihalides, Se2Br2, Se2Cl2, Se2BrCl, SeSCl2, SeSBr2, BrSeSCl, and ClSeSBr, have been observed in the spectrum of a 1:1 molar mixture of S2Cl2 and Se2Br2.The disulfur dichloride and dibromide, as well as the bromide chloride, are also present.Selenium-bromine and sulfur-chlorine linkages are observed to be preferred over selenium-chlorine and sulfur-bromine bonding in these mixtures.The 77Se chemical shifts correlate well with the electronegativity of the directly bonded neighbour but inversely with that of the next-nearest neighbour.Key words: selenium halides, sulfur halides, low valent chalcogen halides, 77Se NMR, Raman spectroscopy.
- Milne, John B.
-
p. 693 - 699
(2007/10/02)
-