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1.
Secondary phosphine sulfides readily undergo addition to divinyl sulfoxide and divinyl sulfone in the presence of KOH (THF, 20–22°C, 1 h) with regiospecific formation of bis[2-(diorganylthiophosphoryl)-ethyl] sulfoxides and sulfones. A dramatic increase in the electrophilicity of the double bond in the monoadduct suggests transfer of the electron-acceptor effect of the thiophosphoryl group directly though space, due to its donor-acceptor interaction with the polarized S-O bond. It was demonstrated by the example of divinyl sulfoxide that, when performed with equimolar amounts of reactants and a weaker base (LiOH), the reaction can be stopped at the stage of formation of the monoadduct.  相似文献   

2.
Reactions of trifluoromethanesulfonamide with divinyl sulfone, divinyl sulfoxide, divinyl sulfide, diphenyl sulfide, vinyl allyl and diallyl ethers was investigated in the presence of oxidation system t-BuOCl + NaI. The reaction with divinyl sulfone afforded a product of 1,5-heterocyclization, 2,6-diiodo-4-[(trifluoromethyl) sulfonyl]thiomorpholine 1,1-dioxide. The same product was obtained in the reaction with divinyl sulfoxide apparently due to its preliminary oxidation to sulfone. In reactions with divinyl sulfide and unsaturated ethers only the oxidation of substrates was observed accompanied with strong tarring; the products of a reaction with trifluoromethanesulfonamide were absent. With diphenyl sulfide a product was formed resulting from the oxidation at the sulfur atom [S(II) → S(IV)], N-(diphenyl-λ4-sulfanylidene)trifluoromethanesulfonamide.  相似文献   

3.
Using relative rate methods, rate constants for the gas-phase reactions of divinyl sulfoxide [CH 2CHS(O)CHCH 2; DVSO] with NO 3 radicals and O 3 have been measured at 296 +/- 2 K, and rate constants for the reaction with OH radicals have been measured over the temperature range of 277-349 K. Rate constants obtained for the NO 3 radical and O 3 reactions at 296 +/- 2 K were (6.1 +/- 1.4) x 10 (-16) and (4.3 +/- 1.0) x 10 (-19) cm (3) molecule (-1) s (-1), respectively. For the OH radical reaction, the temperature-dependent rate expression obtained was k = 4.17 x 10 (-12)e ((858 +/- 141)/ T ) cm (3) molecule (-1) s (-1) with a 298 K rate constant of (7.43 +/- 0.71) x 10 (-11) cm (3) molecule (-1) s (-1), where, in all cases, the errors are two standard deviations and do not include the uncertainties in the rate constants for the reference compounds. Divinyl sulfone was observed as a minor product of both the OH radical and NO 3 radical reactions at 296 +/- 2 K. Using in situ Fourier transform infrared spectroscopy, CO, CO 2, SO 2, HCHO, and divinyl sulfone were observed as products of the OH radical reaction, with molar formation yields of 35 +/- 11, 2.2 +/- 0.8, 33 +/- 4, 54 +/- 6, and 5.4 +/- 0.8%, respectively, in air. For the experimental conditions employed, aerosol formation from the OH radical-initiated reaction of DVSO in the presence of NO was minor, being approximately 1.5%. The data obtained here for DVSO are compared with literature data for the corresponding reactions of dimethyl sulfoxide.  相似文献   

4.
Selective monoaddition of carbonodithioate anions to divinyl sulfoxide gives rise to O-alkyl S-[2-(vinylsulfinyl)ethyl] carbonodithioates [ROC(S)SK, R = Et, Bu; 42–50°C, 6 h, NaHCO3, aqueous benzene].  相似文献   

5.
Sodium sulfide and polysulfides readily (50–55°C, 3 h, aqueous medium) react with alkyl vinyl sulfoxides to afford bis(alkylsulfinylethyl)sulfides and-polysulfides in up to 75% yield. Under comparable conditions the reaction of divinyl sulfoxide with sodium sulfide proceeds by the mechanism of addition-cyclization and results in 1,4-dithiane-1-oxide and 1,4-oxathiane-4-oxide. Microwave activation of the studied reactions allows to increase their rate and efficiency.  相似文献   

6.
Conclusions The main products of the gas-phase pyrolysis (580–600°) of divinyl sulfone are SO2, acetylene, and ethylene; butadiene, benzene, toluene, isomeric xylenes, styrene, and benzothiophene are also formed in smaller amounts. In an H2S atmosphere the pyrolysis of divinyl sulfone is apparently accompanied by a partial reduction of the latter to divinyl sulfoxide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 931–932, April, 1983.  相似文献   

7.
The structure of bis(2-sodiumsulfonylethyl) sulfoxide hexahydrate (1), which was synthesized by the reaction of divinyl sulfoxide with sodium metabisulfite in an aqueous ethanol medium, has been determined by X-ray structural analysis. Both Na+ cations are coordinated by six O atoms of crystallization water molecules and SO3 groups; the coordination sphere is a distorted octahedron. The crystals are stabilized by an extensive network of hydrogen bonds through the water molecules of crystallization.  相似文献   

8.
《Tetrahedron letters》1986,27(22):2471-2474
Alkyl vinyl ketones and divinyl ketones are synthesized from carbonyl compounds and 1-chloro-3-phenylthiopropyl phenyl sulfoxide as a three-carbon homologating agent in good overall yields.  相似文献   

9.
Ethylene glycol dimethacrylate (EGDMA) and ethylene glycol methacrylate 4-vinyl benzoate (EGMAVB) were shown to form 1:1 inclusion complexes with cyclodextrin and were characterized by instrumental techniques. Computational analysis showed that the bent conformation of the included divinyl monomer was more stable than its linear conformation. Complexation of the divinyl monomer with the first CD molecule offered substantial stabilization than with the second CD molecule. The vinyl group included in the CD cavity did not participate in polymerization. As a result, solvent soluble, linear polymers with pendant vinyl unsaturation per repeat unit were obtained. This was unequivocally established by the polymerization of a complex comprising CD and EGMAVB. The unreacted vinyl group can be polymerized in the subsequent step to yield cross-linked products.  相似文献   

10.
Star-shaped poly(vinyl ether)s with narrow molecular weight distributions were obtained from polymer-linking reactions of living polymers with a divinyl compound based on living cationic polymerization. For example, living polymers (DP(n) = 50-300) of isobutyl vinyl ether (IBVE), prepared with a cationogen/EtAlCl(2) at 0 degrees C in hexane in the presence of ethyl acetate, were allowed to react with a small amount of 1,4-cyclohexanedimethanol divinyl ether (DVE-1) to give a star-shaped poly(IBVE) in quantitative yield (100%). In addition, a notable feature of this star-shaped polymer was extremely narrow molecular weight distribution (M(w)/M(n) = 1.1-1.2). The structure of divinyl compounds and reaction conditions for the linking reaction are key factors for achieving quantitative yield of star-shaped polymers. To our best knowledge, this is the first example of selective preparation of star-shaped polymers with narrow molecular weight distribution via one-pot polymer-linking reactions, which has never been achieved in any other mechanisms. The M(w) and the number of arms per molecule ranged from 6 x 10(4) to 30 x 10(4) and 9 to 44, respectively. Thermosensitive star polymers were also synthesized in quantitative yield, and the products were found to undergo sensitive phase separation and physical gelation.  相似文献   

11.
Cationic polymerizations of two series of divinyl ethers were carried out to clarify the effects of their central spacer chain structure on their crosslinking polymerization behavior. One series of the monomers involves divinyl ethers with an oligooxyethylene central spacer chain: diethylene glycol divinyl ether ( O‐3 ), triethylene glycol divinyl ether ( O‐4 ), tetraethylene glycol divinyl ether ( O‐5 ), pentaethylene glycol divinyl ether ( O‐6 ), and heptaethylene glycol divinyl ether ( O‐8 ) (see Scheme 1 ). The other series includes divinyl ethers with an oligomethylene central spacer chain: 1,4‐butanediol divinyl ether ( C‐4 ), 1,6‐hexanediol divinyl ether ( C‐6 ), and 1,8‐octanediol divinyl ether ( C‐8 ). Cationic polymerizations of these monomers were carried out with the hydrogen chloride/zinc chloride (HCl/ZnCl2) initiating system in methylene chloride (CH2Cl2) at ?30 °C ([Monomer]0 = 0.15 M; [HCl]0 = 5.0 mM; [ZnCl2]0 = 0.5 mM). The polymerizations of the oligomethylene‐based divinyl ethers C‐6 and C‐8 caused gel formation at high monomer conversions (~90%), whereas C‐4 formed soluble polymers even at almost 100% monomer conversion. The oligooxyethylene‐based divinyl ethers O‐3 , O‐4 , O‐5 , and O‐6 underwent gel‐free polymerizations up to 100% monomer conversion and O‐8 did so at least up to ~80% conversion. The content of unreacted pendant vinyl groups of the obtained soluble polymers was measured by 1H NMR spectroscopy. In the polymerizations of the oligomethylene‐based divinyl ethers ( C‐4 , C‐6 , and C‐8 ), the vinyl contents of the polymers decreased monotonously with increasing monomer conversion, and their number‐average molecular weights (Mn's) and polydispersity ratios (Mw/Mn's) increased considerably just before the gelation occurred. On the contrary, the vinyl contents of the polymers obtained from the oligooxyethylene‐based divinyl ethers ( O‐3 , O‐4 , O‐5 , O‐6 , and O‐8 ) decreased steeply even in the early stage of the polymerizations and almost all the pendant vinyl ether groups were consumed in the soluble polymers at the final stage of the polymerizations. The oligooxyethylene spacer units adjacent to the pendant unreacted vinyl ether groups may solvate intramolecularly with the carbocationic active center to accelerate frequent occurrence of intramolecular crosslinking reactions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3729–3738, 2004  相似文献   

12.
In this paper, the implementation of the CS-FE/MT model introduced in article 1 is discussed, and computer simulations are performed to evaluate the feasibility of the new theoretical approach. As discussed in article 1, making predictions of surfactant/solubilizate aqueous solution behavior using the CS-FE/MT model requires evaluation of DeltaDeltaG for multiple surfactant-to-solubilizate or surfactant-to-cosurfactant transformations. The central goal of this article is to evaluate the quantitative accuracy of the alchemical computer simulation method used in the CS-FE/MT modeling approach to predict DeltaDeltaG for a single surfactant-to-solubilizate or for a single surfactant-to-cosurfactant transformation. A hybrid single/dual topology approach was used to morph the ionic surfactant sodium dodecyl sulfate (SDS) into the ionic solubilizate ibuprofen (IBU), and a dual topology approach was used to morph the nonionic surfactant octyl glucoside (OG) into the nonionic solubilizate p-aminobenzoate (PAB). In addition, a single topology approach was used to morph the nonionic surfactant n-decyl dimethylphosphine oxide (C10PO) into the nonionic cosurfactant n-decyl methyl sulfoxide (C10SO), the nonionic surfactant octylsulfinyl ethanol (C8SE) into the nonionic cosurfactant decylsulfinyl ethanol (C10SE), and the nonionic surfactant n-decyl methyl sulfoxide (C10SO) into the nonionic cosurfactant n-octyl methyl sulfoxide (C8SO). Each DeltaDeltaG value was computed by using thermodynamic integration to determine the difference in free energy associated with (i) transforming a surfactant molecule of type A into a cosurfactant/solubilizate molecule of type B in a micellar environment (referred to as DeltaG2) and (ii) transforming a surfactant molecule of type A into a cosurfactant/solubilizate molecule of type B in aqueous solution (referred to as DeltaG1). CS-FE/MT model predictions of DeltaDeltaG for each alchemical transformation were made at a number of simulation conditions, including (i) different equilibration times at each value of the coupling parameter lambda, (ii) different data-gathering times at each lambda value, and (iii) simulation at a different number of lambda values. For the three surfactant-to-cosurfactant transformations considered here, the DeltaDeltaG values predicted by the CS-FE/MT model were compared with DeltaDeltaG values predicted by an accurate molecular thermodynamic (MT) model developed by fitting to experimental CMC data. Even after performing lengthy equilibration and data gathering at each lambda value, physically unrealistic values of DeltaDeltaG were predicted by the CS-FE/MT model for the transformations of SDS into IBU and of OG into PAB. However, more physically realistic DeltaDeltaG values were predicted for the transformation of C10PO into C10SO, and reasonable free-energy predictions were obtained for the transformations of C8SE into C10SE and C10SO into C8SO. Each of the surfactant-to-cosurfactant transformations considered here involved less extensive structural changes than the surfactant-to-solubilizate transformations. As computer power increases and as improvements are made to alchemical free-energy methods, it may become possible to apply the CS-FE/MT model to make accurate predictions of the free-energy changes associated with forming multicomponent surfactant and solubilizate micelles in aqueous solution where the chemical structures of the surfactants, cosurfactants, and solubilizates differ significantly.  相似文献   

13.
Crystalline (R)-phenylglycyl-(R)-phenylglycine [(R,R)-1] includes methyl phenyl sulfoxides (2 and 3) and benzyl methyl sulfoxides (4) with high enantioselectivity. The dipeptide exhibited different stereoselectivity depending on four structural isomers of methyl tolyl sulfoxide (C(8)H(10)OS): R for methyl 2-tolyl sulfoxide, S for methyl 3-tolyl sulfoxide, and racemic for methyl 4-tolyl sulfoxide. A structural isomer, benzyl methyl sulfoxide, was included in racemic form. Chlorophenyl methyl sulfoxides 3 (C(7)H(7)ClOS) with a similar volume showed the same enantioselectivity for their recognition. By single-crystal X-ray analyses of these inclusion compounds, it was elucidated that (R,R)-1 molecules self-assembled to form layer structures and included the sulfoxides between these layers and that the origin of the enantioselectivity based on chiral cavities was induced by conformation of the C-terminal phenyl group of the dipeptide. The relative position between the ammonio proton and the C-terminal phenyl group in one molecule of the dipeptide determined the stereochemistry of the methyl sulfinyl groups to be recognized. Various positional isomers of methyl xylyl sulfoxide having the formula of C(9)H(12)OS were subjected to the enantioselective inclusion by (R,R)-1 crystals and these results are also discussed.  相似文献   

14.
The formation constants of the nicotinamide H‐complexes with protonic solvents such as water and ethanol in aqueous dimethyl sulfoxide and aqueous ethanol were determined using 13C NMR data. Free Gibbs energy of nicotinamide donor center (nitrogen heteroatom) solvation was calculated. Gibbs energy of entire nicotinamide molecule solvation was shown to be antibate towards Gibbs energy of a pyridine nitrogen solvation. The solvation state of this molecule fragment must be taken into consideration when analyzing the reagents contributions in the thermodynamics of complexation. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
Considering postulates of the Chemical Weapons Convention, this article is an attempt to improve the decontamination methods of mustard gas (HD) and studying its products of decontamination. It is widely known that mustard gas sulfoxide (HDO; O═S(CH2CH2Cl)2) and sulfone (HDO2; O2═S(CH2CH2Cl)2) undergo further transformations to another compounds, but so far kinetics of these processes have not yet been investigated neither carefully nor thoroughly. This study is focused on determination of kinetics and mechanisms of transformation of HD oxidation products. The primary objective of this study is to assess the impact of selected factors on the kinetics of the HCl elimination reaction and to determine the conditions in which cyclization reactions of divinyl sulfoxide and sulfone proceed. The HDO and HDO2 decay kinetics were monitored in an aqueous solution of the desired pH. The rate of HCl elimination from HDO and HDO2 is strongly dependent on pH. For example, with pH increasing from 9 to 12 the rate of HCl elimination from HDO increased over 1200 times. In solutions of pH 9, HDO loses hydrogen chloride at approximately 100 times slower compared to HDO2, and the difference is reduced with increasing pH. In pH 12 solutions, the rate of hydrogen chloride loss from HDO2 is only 20 times higher than the HCl loss from HDO. Divinyl sulfoxide and sulfone undergo a further transformation in a strongly alkaline environment, leading to cyclization and formation of 1,4‐thioxane sulfoxide and sulfone, respectively. Elimination of HCl from HDO and HDO2 goes with a rapidly increasing rate with increasing pH if alkalinity of the reaction medium is relatively very high (the range of pH 9–12). Furthermore, the conversion of divinyl sulfone and sulfoxide to sulfoxide and sulfone thioxane, respectively, occurs at a measurable rate when the pH of the solution is in the range of 12–14.  相似文献   

16.
The accurate estimation of S-O bond dissociation enthalpies (BDE) of sulfoxides by computational chemistry methods has been a significant challenge. One of the primary causes for this challenge is the well-established requirement of including high-exponent d functions in the sulfur basis set for accurate energies. Unfortunately, even when high-exponent d functions were included in Pople-style basis sets, the relative strength of experimentally determined S-O BDE was incorrectly predicted. The aug-cc-pV(n+d)Z basis sets developed by Dunning include an additional high-exponent d function on sulfur. Thus, it was expected that the aug-cc-pV(n+d)Z basis sets would improve the prediction of sulfoxide S-O BDE. This study presents the S-O BDE predicted by B3LYP, CCSD, CCSD(T), M05-2X, M06-2X, and MP2 combined with aug-cc-pV(n+d)Z, aug-cc-pVnZ, and Pople-style basis sets. The accuracy of these predictions was determined by comparing the computationally predicted values to the experimentally determined S-O BDE. Values within experimental error were obtained for dialkyl sulfoxides when the S-O BDEs were estimated using an isodesmic oxygen transfer reaction at the M06-2X/aug-cc-pV(T+d)Z level of theory. However, the S-O BDE of divinyl sulfoxide was overestimated by this method.  相似文献   

17.
We present a detailed analysis of the structure and infrared spectra of di-vinyl sulfone. The vibrational frequencies of the di-vinyl sulfone molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-311G* basis set. The structural transformation of the chemical agent bis(2-chloroehtyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compounds [Spectrochim. Acta Part A 55 (1999) 121; Spectrochim. Acta Part A 57 (2001) 2417] makes the symmetry of the di-vinyl sulfone molecule an interesting candidate for study. The molecule exists normally in a C(2) configuration. High-energy forms of di-vinyl sulfone with C(S) and C(1) symmetries also exist.  相似文献   

18.
Lipase‐catalyzed regioselective polymerization of divinyl sebacate and triols has been performed in bulk. NMR analysis of the product obtained by the polymerization of divinyl sebacate and glycerol using Candida antarctica lipase at 60°C showed that 1,3‐diglyceride was a main unit and a small amount of the branching unit (triglyceride) was contained. The polymerization of divinyl sebacate with 1,2,4‐butanetriol or 1,2,6‐hexanetriol at 60°C produced a branched polymer. In polymerization at a lower temperature, the regioselectivity was perfectly controlled to give a linear polymer consisting of the α,ω‐disubstituted unit exclusively. The lipase origin and feed ratio of monomers greatly affected the microstructure of the polymer; under selected conditions, regiospecific polymerization was achieved.  相似文献   

19.
We present a detailed analysis of the structure and infrared spectra of 1,4-thioxane. The vibrational frequencies of the 1,4-thioxane molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-31G* basis set. The structural transformation of the chemical agent bis (2-chloroethyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compound(4) makes the symmetry of the 1,4-thioxane molecule an interesting candidate for study. The molecule exists normally in a Cs configuration similar to the chair form of cyclohexane. High-energy forms of 1,4-thioxane with C1 and C2 symmetry also exist.  相似文献   

20.
Liquid-liquid equilibria (LLE) data of the ternary system thiophene + octane + dimethyl sulfoxide at 40 degrees C, 50 degrees C, and 60 degrees C under atmospheric pressure were determined using an equilibrium cell with the standard curve method. The distribution of thiophene between extract and raffinate was measured and a practical formula of equilibria data for industrial extraction was proposed. NRTL model and UNIQUAC model were used to correlate and calculate LLE data of the system, and model parameters were determined using the simplex optimization method and imitative Newton method with a minimized objective function of mole fraction deviation. The rule of thermodynamic equilibria was used to deal with multi-roots problem in correlating process. Agreement between predicted and experimental data was satisfactory. The average absolute deviations of the NRTL and UNIQUAC models of thiophene mass fraction were 0.0040 and 0.0078, respectively. Both NRTL and UNIQUAC models were suitable for the calculation of LLE data of the ternary system thiophene + octane + dimethyl sulfoxide. The correlation accuracy of NRTL model is inferior to that of UNIQUAC model.  相似文献   

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