287-27-4Relevant articles and documents
Radical ring-opening polymerization of five-membered cyclic vinyl sulfone using p-toluenesulfonyl halides
Tanaka, Shimon,Furusho, Yoshio,Endo, Takeshi
, p. 222 - 227 (2013)
Radical ring-opening polymerizations of a five-membered cyclic vinyl sulfone monomer, 2-vinylthiolane-1,1-dioxide (VTDO), was carried out by using p-toluenesulfonyl iodide (TosI) and bromide (TosBr) as radical initiators, and the corresponding ring-opened polymer (PVTDO) was obtained. Both TosI and TosBr were found to work as the radical initiators for the polymerization of VTDO in bulk. The use of TosI gave PVTDOs with a broad, multimodal distribution of molecular weight in low yields. When 10 mol % of TosBr was employed, the isolated yield of PVTDO reached 49%, and the obtained PVTDO had a relatively narrow, monomodal molecular weight distribution of 1.8 with an Mn of 4100.
Photochemical reactions of trimethylene sulfide radical cations in Freon matrices at 77 K
Mel'nikov, Mikhail Ya.,Belevskii, Vladilen N.,Kalugina, Anastasiya D.,Pergushov, Vladimir I.,Tyurin, Daniil A.
, p. 67 - 68 (2008)
Photobleaching (λ = 436 nm) of trimethylene sulfide radical cations (λmax ≈ 460 nm, εmax ≈ 345 dm3 mol-1 cm-1) stabilised in different Freon matrices at 77 K results in the formation of distonic radical cations CH2CHSHCH2·+.
Synthesis, structure, and reactions of a copper-sulfido cluster comprised of the parent Cu2S unit: {(NHC)Cu}2(μ-S)
Zhai, Junjie,Filatov, Alexander S.,Hillhouse, Gregory L.,Hopkins, Michael D.
, p. 589 - 595 (2015/12/26)
The synthesis of the first CuI2(μ-S) complex, {(IPr?)Cu}2(μ-S) (IPr? = 1,3-bis(2,6-(diphenylmethyl)-4-methylphenyl)imidazol-2-ylidene; 1), has been accomplished via three synthetic routes: (1) salt metathesis between (IPr?)CuCl and Na2S; (2) silyl-deprotection reaction between (IPr?)Cu(SSiMe3) and (IPr?)CuF; and (3) acid-base reaction between (IPr?)Cu(SH) and (IPr?)Cu(OtBu). The X-ray crystal structure of 1 exhibits two two-coordinate copper centers connected by a bent Cu-S-Cu linkage. Application of these synthetic routes to analogous precursors containing the sterically smaller ligand IPr (1,3-bis(2,6-di-isopropylphenyl)imidazol-2-ylidene), in place of IPr?, resulted in the formation of a transient product proposed as {(IPr)Cu}2(μ-S) (2), which decomposes quickly in solution. The instability of 2 probably results from the insufficient steric protection provided by IPr ligands to the unsaturated Cu2(μ-S) core; in contrast, 1 is stable both in solution and solid state for weeks. The nucleophilic sulfido ligand in 1 reacts with haloalkyl electrophiles (benzyl halides and dibromoalkanes) with formation of C-S bonds, affording (IPr?)Cu(SCH2Ph) and cyclic thioethers, respectively.
A kinetic investigation, supported by theoretical calculations, of steric and ring strain effects on the oxidation of sulfides and sulfoxides by dimethyldioxirane in acetone
Hanson, Peter,Hendrickx, Ramon A. A. J.,Lindsay Smith, John R.
supporting information; experimental part, p. 65 - 84 (2011/01/07)
The oxidations of alkyl 4-nitrophenyl, and dialkyl, sulfides and sulfoxides by dimethyldioxirane in acetone occur by concerted mechanisms but the sulfides respond differently from the sulfoxides to variation in the alkyl group. The reactions of the sulfides are inhibited by the steric effects of alkyl groups and these predominate over their inductive effects. By contrast, the reactions of these limited sets of sulfoxides are insensitive to alkyl steric effects but there is an indication of steric acceleration when a broader set of sulfoxides is considered. This behaviour is rationalised in terms of the differences in dipolar charge and its solvation between the ground state and transition state for the two types of substrate. The oxidations of cyclic sulfides and sulfoxides also exhibit contrasting behaviour. The reactivity of the sulfides is insensitive to ring strain but is explicable in frontier orbital terms whereas that of the sulfoxides is partly dependent upon the change in ring strain between reactant and product on oxidation, a difference rationalised in terms of the relative positions of the transition states in the reaction coordinates of the two oxidations. The reactivity of 4-, 5- and 6-membered cyclic sulfoxides is also dependent on a ring-size related property of the transition state. Calculations at the B3-LYP/6-31G* level of density functional theory on both ground states and transition states, including simulation of solvation by acetone, strongly support the mechanistic conclusions reached in this and earlier work.
Synthesis of 2-alkyl(aryl)thietanes
Volynskii,Shevchenko
, p. 109 - 117 (2008/02/03)
Thietane and its 2-substituted derivatives were synthesized. A general preparation procedure for the synthesis of thietanes bearing alkyl and aryl substituents in the α-position was developed. Using this procedure, 2-substituted thietanes can be obtained from cheap and easily accessible raw materials in three steps. 2-R-Thietanes (where R = H, CH3, C 4H9, C5H11, C6H 13, C6H5) and the corresponding sulfoxides and sulfones were synthesized and examined. Intermediate and by-products of the synthesis were studied. Nauka/Interperiodica 2007.
The macrocyclization reaction of terminal dibromoalkanes with sulfide on alumina. The use of a solid support as an alternative to the high dilution technique
Tan,Pagni,Kabalka,Hillmeyer,Woosley
, p. 7709 - 7712 (2007/10/02)
The reaction of a series of terminal dibromoalkanes with S-2 on Al2O3 has been examined. The use of a solid support for the macrocyclization represents a viable alternate procedure to the more traditional high dilution technique in solution. The cyclization also occur with thioacetamide on unactivated alumina.
ESR Studies of the Thietane and Thiirane Radical Cations in Freon Matrices. Evidence for Ethylene Molecule Extrusion from the ? Thiirane Dimer Radical Cation .+>
Qin, Xue-Zhi,Meng, Qing-cheng,Williams, Francon
, p. 6778 - 6788 (2007/10/02)
ESR spectroscopy has been used to study the structures and reactions of the radical cations produced from the three- and four-membered sulfur-containing ring compounds, thiirane and thietane, the radical cations being generated by γ irradiation of dilute solutions of the parent compounds in Freon matrices at 77 K.With use of CFCl3 as the matrix, the monomer radical cations have been identified and characterized as having (2)B1 ring-closed structures with the unpaired electron localized on the sulfur atom.The hyperfine coupling to the four equivalent β-hydrogens in the thietane cation (31.1 G) is normal, but the corresponding value for the thiirane cation (16.1 G) is lower by almost a factor of 2, suggesting that hyperconjugation to methylene groups is much reduced in three-membered rings.In the more mobile CFCl2CF2Cl and CF3CCl3 matrices, dimer radical cations of thiirane and thietane are produced by the combination of a monomer radical cation with a neutral molecule at low temperatures (2?*1 S-S bond.Both of the dimer cations are unstable above 105 K in the CFCl2CF2Cl matrix, the thietane dimer radical cation decomposing to give the 2-thietanyl radical as a result of hydrogen atom or proton transfer, whereas the thiirane dimer radical cation undergoes a novel reaction involving the extrusion of an ethylene molecule.Evidence for ethylene formation in the latter reaction comes indirectly from the ESR observation of secondary radicals with the structure RCH2CH2 on annealing γ-irradiated solutions of thiirane in CFCl2CF2Cl.Similar radicals are also generated in γ-irradiated thiirane solutions in CF3CCl3 at 145-150 K, the ESR spectrum being indistinguishable from that of identically treated ethylene solutions.The ethylene extrusion is depicted as a concerted reaction in which the driving force is supplied by the transfer of the unpaired electron from the ?* (S-S) orbital of the dimer cation to a vacant p orbital on the terminal sulfur atom of the remaining C2H4S2+ moiety.
DIOXYPHOSPHORANES, AN EMERGING CLASS OF VERSATILE REAGENTS FOR ORGANIC SYNTHESIS
Kelly, Jeffery W.,Robinson, Philip L.,Evans, Slayton A.
, p. 147 - 150 (2007/10/02)
Several ?-dioxyphosphoranes have been prepared and their structural characterizations using NMR techniques support the trigonal bipyramidal conformer as the most stable for the acyclic phosphoranes.Their utility in smooth conversions of hydroxylated substrates to the corresponding X-heterocycles is documented.
THE CHEMISTRY OF α,ω-MERCAPTOALCOHOLS IN THE PRESENCE OF DIETHOXYTRIPHENYLPHOSPHORANE. TEMEPERATURE DEPENDENCE OF CYCLODEHYDRATIONS AND S-ETHYLATIONS
Robinson, Philip L.,Kelly, Jeffery W.,Slayton, A. Evans
, p. 59 - 70 (2007/10/02)
Diethoxytriphenylphosphorane (DTPP) is easily prepared by oxidative addition of triphenylphosphine with diethyl peroxide.DTPP converts a variety of mercaptoalcohols to cyclic sulfides as well as hydroxythioethers.The temperature dependence (+25 --> -25 deg C) of the product distribution has synthetic petential.
