15848-07-4Relevant academic research and scientific papers
Regioselective 1,3-dipolar cycloadditions of a 'thiocarbonyl-methanide' ((alkylidenesalfonio)methanide) with aromatic sulfines
Mloston, Grzegorz,Linden, Anthony,Heimgartner, Heinz
, p. 31 - 40 (1996)
Reaction of the spirocyclic 2,5-dihydro-1,3,4-thiadiazole 7 and thiobenzophenone S-oxide (6a) in THF at 45° yielded the spirocyclic 1,3-dithiolane 1-oxide 8, thiirane 9, and the diazane derivative 10 in a ratio of 61:15:23 (Scheme 2) The formation of 8 is
Photochemical formation and reactivities of substituted oxathiiranes in low-temperature argon matrices
Reisenauer, Hans Peter,Mloston, Grzegorz,Romanski, Jaroslaw,Schreiner, Peter R.
body text, p. 6269 - 6275 (2011/12/02)
Thiocarbonyl S-oxides (sulfines) derived from aliphatic and cycloaliphatic thioketones were irradiated in argon matrices at 10 K, and the resulting oxathiiranes were identified by comparison of computed and experimental IR spectra. Upon photolysis at 10 K, depending on the substitution pattern, the oxathiiranes underwent either H-shift reactions or regioselective ring enlargements to form the corresponding thioesters. After warming of the matrix material to 38-40 K, the oxathiiranes underwent fast desulfurization to yield the corresponding ketones. Density functional theory (DFT) computations at the B3LYP/6-311+G(3df,3pd) level suggest that the desulfurizations of oxathiiranes occurred as bimolecular processes with activation enthalpies near 0 kcal mol-1.
Kinetics and Mechanism of the Methyltrioxorhenium-Catalyzed Sulfoxidation of Thioketones and Sulfines
Huang, Ruili,Espenson, James H.
, p. 6374 - 6376 (2007/10/03)
Kinetic studies have been carried out on the oxidation of thiobenzophenones and thiocamphor by hydrogen peroxide and on the second step in the sequence, oxidation of the resulting sulfines (Ar2C= S=O). The first reaction follows the pattern now common to methyltrioxorhenium/H2O2 reactions, in that the rate constant for the reaction between the peroxorhenium intermediate and the thioketone follows a Hammett correlation such that electron-releasing substrates react more rapidly. The reaction constant is p = -1.12. However, the plot of log(kX/kH) for the sulfines against 2σ, determined over the range -1.6 2 under these conditions rather than undergoing disproportionation to SO2 and S. Also, SO was trapped with a 1,3-diene as a thiophene-1-oxide.
Matrix isolation of diphenylsulfene and diphenyl-α-sultine
Sander, Wolfram,Kirschfeld, Andreas,Halupka, Martin
, p. 981 - 986 (2007/10/03)
Diphenylsulfene (5) and diphenyl-α-sultine 6 were generated in cryogenic matrices by three independent routes: (i) the thermal reaction of diphenylcarbene (8) and SO2, (ii) the photochemically induced hetero Wolff rearrangement of sulfonylcarbe
Reaction of Thioketones with Carbonyl Oxides and 3,3-Dimethyl-1,2-dioxirane. Cycloaddition vs. Oxygen Atom Transfer
Tabuchi, Toshihiko,Nojima, Masatomo,Kusabayashi, Shigekazu
, p. 3043 - 3046 (2007/10/02)
The ozonolysis of vinyl ethers 1a, b in the presence of adamantane-2-thione 4a and bicyclononan-9-thione 4b gave in each case the corresponding thioozonides 5a-c in moderate yields, whilst ozonolysis of a mixture of vinyl ethers 1a-d and thiobenzophenone derivatives 4f-h gave the corresponding thione S-oxides 8f-h in isolated yields of 10-40percent, together with the benzophenones 7f-h. 3,3-Dimethyl-1,2-dioxirane, generated in situ from the reaction of acetone and 'oxone' (2KHSO5-KHSO4-K2SO4), transferred an oxygen atom to compounds 4a, f, g, i providing the thione S-oxides 8a, f, g, i in 29-97 percent yield.
Methoxide-Catalyzed Decomposition of Diarylmethyl (Arylsulfonyl)methyl Sulfoxides: A Sulfine-Forming Elimination on the (E1cB)rev/(E1cB)irrev Borderline
Kice, John L.,Kupczyk-Subotkowska, Lidia
, p. 1424 - 1430 (2007/10/02)
In 7:3 CH3OH-DMSO (v/v) in the presence of methoxide ion, diarylmethyl (arylsulfonyl)methyl sulfoxides (Ar2CHS(O)CH2SO2Ar') 4, undergo elimination remarkably easily to afford the diarylsulfine and the aryl methyl sulfone (eq 4).Comparison of the rate of cleavage of 4 (kelim) and the rate of disappearance of the 1H NMR signal (kCHSO) for the Ar2CHS(O) proton in CD3OD-DMSO shows that the mechanism for the elimination is on the (E1cB)rev/(E1cB)irrev borderline, (kCHSO/kelim) ranging from 1.2 to 5.2, depending on the nature of the Ar and Ar'groups in 4.Slight changes in structure can shift the mechanism from (E1cB)rev to (E1cB)irrev as a result of their effect on the partitioning of the α-sulfinyl carbanion intermediate (Ar2CS(O)CH2SO2Ar') 5, between cleavage to diarylsulfine plus ArSO2CH2- (step kii, eq 8) and protonation to regenerate 4 (step k-i).Structural changes that make Ar'SO2CH2 a better leaving group increase kii/k-i and shift the mechanism toward (E1cb)irrev as does also an increase in the percentage of DMSO in the solvent.Structural changes in Ar that enhance the stability of 5 decrease kii/k-i and shift the mechanism toward (E1cb)rev.It is also shown that for 4 in general kii appears larger than would be expected for a leaving group of the basicity of Ar'SO2CH2-.Repulsion between the dipoles of the S(O) and SO2 groups in 5 is thought to be responsible.
Elimination Reactions of Alkanesulfinyl Derivatives: Mechanism and Reactivity in Base-Induced Sulfine Formation from Methyl Diarylmethanesulfinates
Kice, John L.,Rudzinski, Juliusz J.
, p. 2414 - 2421 (2007/10/02)
Upon treatment in methanol at room temperature with methoxide ion methyl diarylmethanesulfinates, ArAr'CHS(O)OCH3 (1), and methyl 9-fluorenesulfinate (2) undergo elimination readily to afford the corresponding sulfines (3 and 4) in quantitative yield.Studies in CD3O-/CD3OD show that, surprisingly, elimination of 1 to give 3 is significantly faster than nucleophilic substitution by methoxide ion at the sulfinyl group (exchange of CH3O by CD3O).Even more unexpected, the kinetic isotope effect for elimination of 2-9-d (kH/kD=6.1) and absence of detectable H/D exchange of the methine proton of 1 in CD3OD prior to sulfine formation extablish that, even though the leaving group is MeO-, the elimination takes place by either an irreversible ElcB or an E2 mechanism, rather than the reversible ElcB mechanism found (ref 4 and 7) for the analogous sulfene-forming elimination of arylmethanesulfonate esters with oxyanion leaving groups of comparable pKa.Reaction of amines with 2 in methanol also gives sulfine 4, and the amine-induced elimination, which has a large Broensted β, also proceeds by either an (ElcB)irrev or an ElcB-like E2 mechanism.Why sulfine-forming eliminations of 1 and 2 favor an (ElcB)irrev or E2 mechanism whereas sulfene-forming eliminations of arylmethanesulfonates with even better leaving groups proceed by an (ElcB)rev mechanism is considered and a possible explanation presented.
