10026-03-6Relevant articles and documents
Heavy atom analogues of 1,2,3-dithiazolylium salts: Preparation, structures and redox chemistry
Risto, Maarit,Assoud, Abdeljalil,Winter, Stephen M.,Oilunkaniemi, Raija,Laitinen, Risto S.,Oakley, Richard T.
, p. 10100 - 10109 (2008)
Synthetic routes to salts of the benzo[1,2,3]thiatellurazolylium cation [2c]+ and its selenium analogue [2b]+ are described. Access to the cation frameworks involves the intermediacy of N,N,S-trisilylated 2-aminobenzenethiol. The latter reacts smoothly with selenium and tellurium halides ECl4 (E = Se, Te) to afford the desired heterocyclic benzo cations [2b]+ and [2c]+ as their chloride salts. Anion exchange provides the corresponding GaCl4-, OTf - and TeCl5- salts of [2c]+, all of which have been characterized by X-ray crystallography. While the gallate salts of the sulfur and selenium cations [2a]+ and [2b]+ crystallize as ion-paired cations and anions, salts of [2c]+ adopt solid-state structures that display strong association of the cations via short intermolecular Te-N′ bonds. However, crystallization of [2c]+ salts in dichloroethane in the presence of GaCl3 leads to cleavage of the dimers and the formation of a Lewis acid adduct at nitrogen. Reduction of the benzo cations [2a,b]+ affords the respective radicals 2a,b, both of which have been characterized by electron paramagnetic resonance (EPR) spectroscopy. Attempts to generate the corresponding radical 2c have been unsuccessful, although a material of nominally correct elemental composition can be generated by chemical reduction. The energetics of association of [2a,b,c]+ in solution has been probed by means of density functional theory calculations using the polarized continuum model. The results suggest that the dimeric nature of the Te-centered cation is retained in solution. The strength of the interaction is, however, less than in N-alkylated tellurodiazolylium salts.
The bicyclic polyselenium cation Se102+ in the structure of Se10[Bi4Cl14]
Beck, Johannes,Eck, Steffen J.
, p. 1910 - 1912 (2010)
In the ternary system Se/Bi/Cl a new polycation containing phase besides the already known Se4[Bi4Cl14], Se 8[Bi4Cl14], and Se10[Bi 5Cl17] was discovered. Red, transparent, plate shaped crystals of Se10[Bi4Cl14] were formed by reaction of Se/SeCl4/BiCl3 in 15:1:8 molar ratio in evacuated glass ampoules applying a temperature gradient from 90 to 80 °C. The crystal structure consists of bicyclic Se102+ cations and of layered chloridobismutate anions with the cations located between the anionic planes. The atoms of the cation form a six membered ring with a Se 4 chain bridging over the 1,4 positions of the Se6 ring. The anions are made up of BiCl7 polyhedra connected by common edges to layers 2∞[Bi4Cl14 2-]. Se4[Bi4Cl14], Se 8[Bi4Cl14], Se10[Bi 4Cl14], and Te8[Bi4Cl14] all contain an anion of identical formula and two-dimensional connectivity, but these polymeric chlorido-bismutates are not isostructural. The structural differences are discussed on basis of the different topologies of the nets made up by the bismuth atoms.
Thermal transformations of gold(III) complexes with chalcogen tetrachlorides
Volkov,Fokina,Pekhn'o,Yanko
, p. 121 - 124 (2008/10/08)
Thermal transformations of chalcogen chloride complexes of gold(III) of the AuCl3L type (L = SCl4, SeCl4, TeCl 4) have been investigated in the temperature range of 20-500°C. The melting points are found to be 108°C for AuCl3SCl 4, 153°C for AuCl3TeCl4, and 201°C for AuCl3SeCl4. For decomposition according to the scheme AuCl3L → AuCl3 + L, the thermal stability sequence of the complexes is AuCl3SCl4 3SeCl 4 3TeCl4 (133, 260, and 340°C, respectively). The role of gold trichloride → gold monochloride thermolysis and its dependence on the presence of chlorine vapor are demonstrated. The presence of chlorine vapor widens the temperature region of existence of AuCl3 and raises the gold monochloride → metallic gold thermolysis end temperature. The general scheme of thermal transformations of chalcogen chloride complexes of gold(III) is given: AuCl3L (s) →T1 AuCl3L(l) →-LT2 AuCl3(s) →-Cl2 T3 AuCl(s) →-Cl2T4 Au (s). Therefore, the thermal decomposition of AuCl3L complexes proceeds with the sequential reduction of gold: Au(III) → Au(I) → Au(0).
Reactivity of SeOCl2 with titanium and zirconium tetrachlorides. the unexpected formation of a μ-oxo-bridged titanium(iv) derivative
Calderazzo, Fausto,D'Attoma, Michele,Marchetti, Fabio,Pampaloni, Guido
, p. 2497 - 2498 (2007/10/03)
The reaction of TiCl4 with SeOCl2 affords the μ-oxo derivative [TiCl3(SeOCl2)2]2(μ-O) through a deoxygenation reaction of SeOCl2 to SeCl4 whereas ZrCl4 gives 1:1 or 1:2 adducts of formula ZrCl4(SeOCl2)n, n = l, 2. The Royal Society of Chemistry 2000.
Syntheses of THF solutions of SeX2 (X = Cl, Br) and a new route to selenium sulfides SenS8-n (n = 1-5): X-ray Crystal Structures of SeCl2(tht)2 and SeCl2·tmtu
Maaninen, Arto,Chivers, Tristram,Parvez, Masood,Pietikaeinen, Jarkko,Laitinen, Risto S.
, p. 4093 - 4097 (2008/10/08)
A simple and efficient synthesis of solutions of pure SeCl2 in THF or dioxane (ca. 0.4 M) at 23 °C was achieved by treatment of elemental selenium with an equimolar amount of SO2Cl2. SeCl2 was characterized by 77Se NMR and Raman spectra. SeCl2 forms 1:1 or 1:2 adducts with tetramethylthiourea (tmtu) or tetrahydrothiophene (tht), respectively. The crystal structure of SeCl2·tmtu (1) reveals a T-shaped geometry [d(Se-Cl) = 2.443(4) A] with weak intramolecular Se-Cl interactions [d(Se-Cl) = 3.276(4) A]. Crystals of 1 are triclinic, space group P1, with a = 8.473(3) A, b = 9.236(3) A, c = 7.709(4) A, α = 109.90(3)°, β= 92.26(4)°, γ = 107.89(3)°, V = 532.9(4) A 3, and Z =2. The complex SeCl2(tht)2 (2) adopts a square planar geometry with d(Se-Cl) = 2.4149-(8) A. Crystals of 2 are monoclinic, space group C2/c, with a - 15.6784(8) A, b = 9.1678(4) A, c = 9.1246(4) A, β= 110.892(2)°, V = 1225.3(1) A,3 and Z = 4. The reaction of Ph3PS with SeCl2 gives Ph3PCl2 and a complex mixture of selenium Sulfides SenS8-n (n = 1-5), which were identified by 77Se NMR. Halogen exchange between SeCl2 and Me3SiBr in THF yields thermally unstable SeBr2 (ca. 0.4 M) characterized by 77Se NMR and Raman spectra.
Synthesis and characterization of selenium-nitrogen chlorides: Force-field calculations for the Se3N2Cl+ cation
Siivari, Jari,Chivers, Tristram,Laitinen, Risto S.
, p. 4391 - 4395 (2008/10/08)
The explosive black solid 3-chloro-1,3,4,2,5-triselenadiazolium chloride, Se3N2Cl2, has been prepared in high yield by three different reactions: (a) from [(Me3Si)2N]2Se and a mixture of SeCl4 and Se2Cl2 designed to give a Se:Cl ratio of 1:3, (b) from [(Me3Si)2N]2Se and SeOCl2 in a 1:2 molar ratio, and (c) from Me3SiN3 and Se2Cl2 in a 2:3 molar ratio. The related dimer (Se3N2Cl)2 is obtained as an explosive dark brown powder by two routes: (a) from equimolar amounts of Se4N4 and Se2Cl2 and (b) from [(Me3Si)2]N]2Se and a mixture of SeCl4 and Se2Cl2 designed to give a Se:Cl ratio of 2:5. In all reactions the reagents were mixed in dichloromethane at -78 or -30°C and then allowed to warm up to room temperature. These new selenium-nitrogen chlorides have been identified by complete elemental analyses and by infrared spectroscopy. The fundamental vibrations for the Se3N2Cl+ cation were calculated using a general valence force-field approach and were used to assign the infrared spectrum of the cation. The reaction of Se3N2Cl2 with SO2Cl2 in dichloromethane at -78°C produces an unstable selenium-nitrogen chloride, characterized by 14N and 77Se NMR spectroscopy, which decomposes to give a mixture of selenium chlorides and N2.
Reactivity of Sulphuryl Chloride in Acetonitrile with the Elements
Woolf, Alfred A.
, p. 3325 - 3330 (2007/10/02)
Sulphuryl chloride in MeCN reacts with all but the most refractory elements to give mainly solvated chlorides at or below 300 K in contrast with SO2Cl2 alone which requires at least twice this temperature.There is evidence for an ionic mechanism based on analogy, thermochemistry, transport measurements and additive effects.The instability of these solutions leading to polymerization, together with its inhibition, is described.Sulphur dioxide formed in reactions seldom plays a reductive role apart from influencing formation of the mixed-valence Tl4Cl6.Semiquantitative kinetic measurements in different solvents emphasize the uniqueness of MeCN.For most elements attack is diffusion controlled across surface films giving a parabolic dependence on time which can be linearized if film growth is prevented by changing the solvent mix.The varied nature of these surface films vitiates any simple relation between rate and periodicity.Some applications are indicated.
Low Temperature Raman Spectra of Dichlorosulfane (SCl2), Tetrachlorosulfurane (SCl4), Dichlorodisulfane (S2Cl2) and Dichlorodiselane (Se2Cl2)
Steudel, Ralf,Jensen, Detlef,Plinke, Bettina
, p. 163 - 168 (2007/10/02)
The Raman spectrum of commercial sulfur dichloride shows strong lines due to SCl2 and S2Cl2 and weak Cl2 lines at 25 deg C, but strong SCl2 and SCl4 signals at -100 deg C (the latter are superimposed on the S2Cl2 lines).Thus, the intense Raman effect of SCl4 can be used to detect small amounts of chlorine in SCl2.Mixtures of SCl2 and Cl2 (1:15) yield the Raman spectrum of SCl4 at -140 deg C, while at 25 deg C not trace of this compound can be detected.The spectra of SCl4 and α-SeCl4 are quite different, indicating different molecular and/or crystal structures, although ECl3(1+) ions (E = S, Se) are present in both cases.While Se2Cl2 dimerizes reversibly below -50 deg C, S2Cl2 neither dimerizes nor isomerizes on cooling.The S2Cl2 dimer is characterized by a Raman line at 215 cm-1 the intensity of which was used to calculate an enthalpy of dimerization as of -17 kJ/mol. - Key words: Raman Spectra, Sulfur Chlorides, Selenium Chlorides
