59507-56-1Relevant academic research and scientific papers
Polycarbon Disulfides SCnS (n = 1-3) and Their Protonated and Methylated Forms (HCnS2+ and CH3CnS2+): Tandem Mass Spectrometry and ab Initio MO Study
Wong, Ming Wah,Wentrup, Curt,Flammang, Robert
, p. 16849 - 16856 (1995)
Dissociative ionization of 4,5-bis(methylthio)-1,2-dithiole-3-thione (1) has allowed the detection of a series of carbon disulfide radical cations, SCnS.+ (n = 1-3), and their S-methylated forms, CH3SCnS+, in the gas phase of a mass spectrometer.The connectivities and stabilities of these ions and the corresponding neutrals have been probed by collisional activation (CA) and neutralization-reionization (NR) mass spectrometry.Moreover, the sites of protonation and cationic methylation of the polycarbon disulfides have been investigated by a combination of flash vacuum pyrolysis, chemical ionization, and CAMS (FVP/CI/MS/MS).The experimental results are supported by ab initio MO calculations at the QCISD(T)/6-311+G(2d,p) + ZPVE level.Both experiments and calculations indicate that the most favorable site of protonation and methylation is the carbon atom for C2S2 and C3S2 but a sulfur atom for CS2.The proton affinities (298 K) of C2S2 and C3S2 are predicted to be 842 and 818 kJ mol-1, respectively.
A simple and safe procedure for bis(methylthio)- and bis(ethylthio)acetylene
Verkruijsse,Brandsma
, p. 818 - 818 (1991)
The acetylenic derivatives bis(methylthio)- and bis(ethylthio)acetylene were obtained in high yield by addition of alkyl thiocyanates to solutions of sodium acetylide in liquid ammonia.
Pd- and Ni-catalyzed cross-coupling reactions of functionalized organozinc reagents with unsaturated thioethers
Melzig, Laurin,Metzger, Albrecht,Knochel, Paul
supporting information; experimental part, p. 2948 - 2956 (2011/04/16)
A variety of unsaturated thioethers have been subjected to cross-coupling reactions with functionalized zinc reagents in the presence of a transition-metal catalyst. Three different catalytic systems based on Pd(OAc)2 or [Ni(acac)2] and the ligands S-Phos or DPE-Phos gave the best results. N-Heterocyclic thioethers based on a pyridine, pyrimidine, pyrazine, pyridazine, triazine, benzothiazole, benzoxazole, pyrrole, or quinazoline ring, as well as thiomethylacetylenes, serve as electrophiles in this cross-coupling reaction. Aryl-, heteroaryl-, benzylic, and alkylzinc halides with sensitive functionalities, such as ester, nitrile, or ketone groups react at ambient temperature with unsaturated thioethers using a Ni catalyst. The corresponding Pd-catalyzed reactions require slightly higher temperatures. Large-scale cross-coupling experiments (10-20 mmol) with N-heterocycles are also reported.
A novel palladium-catalyzed cross-coupling of thiomethylated alkynes with functionalized organozinc reagents
Melzig, Laurin,Stemper, Jeremy,Knochel, Paul
experimental part, p. 2085 - 2091 (2010/08/19)
A range of methylthio-substituted acetylenes undergo smooth palladium-catalyzed cross-coupling reactions with functionalized aryl-, heteroaryl-, and alkylzinc reagents using the Pd(OAc)2/DPE-Phos catalytic system at 25 or 50 C without the need for copper salts. Georg Thieme Verlag Stuttgart.
Thioacylthioketenes by Pyrolysis of 1,3-Dithiethanes and 1,2-Dithiole Derivatives
Kappe, C. Oliver,Pedersen, Carl Th.,Catel, Jean-Marie,Mollier, Yves
, p. 351 - 356 (2007/10/02)
Thioacylthioketenes are formed by flash vacuum pyrolysis (FVP) of 1,3-dithiethanes 6, 1,2-dithiole-3-thiones 11, 14, 15, 3-iodo-1,2-dithiolylium iodide 9, 3-methylthio-1,2-dithiolylium iodides 16, 17 and 1,2-dithiol-3-one tosylhydrazone sodium salt 10.They show IR absorption in the region 1754-1700 cm-1 due to the C=C=S grouping.It is proposed based on the results obtained that 1,2-dithiol-3-ylidenes (1,2-dithiole carbenes) rearrange to give thioacylthioketenes which further rearrange forming thiete-2-thiones.The latter finally fragment into carbon disulfide and alkynes.Formation of C3S2 has been observed in the pyrolysis of the dithiethanes and 1,2-dithiole-3-thione.
Vinylidene, acetylide, and carbene complexes from reactions of 2,5-dithiahex-3-yne (MeSC≡CSMe) with Cp(PMe3)2Ru+
Miller, David C.,Angelici, Robert J.
, p. 79 - 89 (2008/10/08)
The alkyne MeSC≡CSMe initially displaces Cl- in Cp(PMe3)2RuCl at room temperature in MeOH to form the sulfur-bound alkyne complex {Cp(PMe3)2Ru[S(Me)C≡CSMe]}PF6 (1). When it is warmed, 1 rearranges to the vinylidene complex [Cp(PMe3)2Ru=C=C(SMe)2]PF6 (2). Complex 2 is reduced by Na[HBEt3] or Na/Hg to give the thioacetylide Cp(PMe3)2Ru-C≡CSMe (5) and MeSSMe. The vinylidene complexes [Cp(PMe3)2Ru=C=C(R)(SMe)]+ (6, R = H; 7, R = Me) are formed by electrophilic addition to the β-carbon of the thioacetylide 5. Addition of CuCl to 5 forms Cp(PMe3)2Ru(C≡CSMe)(CuCl) (8), in which the copper is π-bound through the C≡C group. Reaction of 6 with methanol and ethanol yields the alkoxycarbene complexes [Cp(PMe3)2Ru=C(OR)(CH2SMe)]BF4 (11a, R = Me; 11b, R = Et). Deprotonation of 11a with NaOMe yields the vinyl complex Cp(PMe3)2Ru[C(OMe)=C(H)SMe] (12). Addition of [Me3O]BF4 to complexes 6 and 7 yields the first examples of sulfoniovinylidene dicationic complexes [Cp(PMe3)2Ru=C=C(R)(SMe2)](BF4) 2 (9, R = H; 10, R = Me). An X-ray diffraction investigation shows that 9 crystallizes in space group P21/n with a = 16.641 (2) A?, b = 8.861 (1) A?, c = 18.168 (2) A?, β = 114.80 (1)°, and Z = 4. Complexes 7 and 10 undergo one- and two-electron reductions, respectively, to give the acetylide Cp(PMe3)2Ru-C≡CMe (14) and MeSSMe (for 7) or SMe2 (for 10). Complexes 6 and 9 are readily deprotonated to give 5 and the sulfonioacetylide [Cp(PMe3)2Ru-C≡CSMe2]BF4 (13), respectively. Mechanisms of the reactions and structural features of the vinylidenes are discussed.
Analysis of Radicals from Flames by Scavenging with Dimethyl Disulfide
Hausmann, M.,Homann, K. H.
, p. 1308 - 1312 (2007/10/02)
Larger hydrocarbon radicals in flames, which are difficult to detect by optical methods, can be analyzed quantitatively by radical scavenging with dimethyl disulfide in the condensed phase. - Gas samples taken from a sooting ethyne/oxygen flame by a nozzle beam were frozen at liquid-N2-temperature on the inner surface of a hollow sphere simultaneously with the radical scavenger dimethyl disulfide.The latter was admitted in large excess as a gas and was condensed uniformly on the inner wall of the sphere.The mixture of condensable stable flame products and scavenging products in the excess CH3SSCH3 was separated and identified by GC/MS. - Larger hydrocarbons (CxHy, x >= 6) condensed quantitatively.H, CH3, C4H3 and the phenyl radical were scavenged as mono(methylthio) compounds; C2 and the carbenes CH2, C3H2, C5H2 yielded bis(methylthio) compounds; other bis(methylthio) compounds observed were C2nH2(SCH3)2 with n = 1, 2, 3 and 4.CH, C3H and C2H3 were identified by the respective tris(methylthio) compounds.Any consecutive reactions of radicals with stable flame products and their recombinations in the cold trap were supressed by their scavenging reaction.
Radical Ions, 79. ESR Evidence for Tetra(methylthio)thiophene and Tetra(methylthio)ethene Radical Cations During the Oxidative Sulfuration of H3CS-CC-SCH3 by S2Cl2/AlCl3 and H3CSCl/AlCl3
Bock, H.,Rittmeyer, P.
, p. 419 - 426 (2007/10/02)
Di(methylthio)acetylene H3CS-CC-SCH3 reacts with S2Cl2 in AlCl3/H2CCl2 solution to the tetra(thiomethyl)thiophene radical cation (H3CS)4C4S.+ and with H3CSCl to the tetra(thiomethyl)ethene radical cation (H3CS)2CC(SCH3)3.Their ESR spectra
SCAVENGING OF RADICALS FROM THE GAS PHASE BY FREEZING WITH DIMETHYL DISULFIDE: 2. RADICALS FROM DISCHARGES AND A FLAME OF ACETYLENE.
Kubitza,Schottler,Homann
, p. 695 - 700 (2007/10/02)
The method of detecting radicals from low-pressure gas-phase systems by scavenging with dimethyl disulfide (DMD) has been applied to microwave discharges in C//2H//2/He mixtures and to a C//2H//2/O//2 flame. It was accomplished by condensing a supersonic nozzle beam from the reaction system together with a beam of DMD on a liquid-N//2 cooled surface. The scavenging products were measured by GC/MS after warming-up. Radicals measured in the discharge were C//2H, C//4H, C//6H, C//3H//2, C//2 besides H atoms. Preliminary measurements on the flame showed that C//6H//5 (phenyl), CH//2, C//3H//2, besides H and O atoms were prominent radicals at the end of the oxidation zone. The concentration of phenyl is of the same order as that of e. g. naphthalene.
