3705-95-1Relevant academic research and scientific papers
Formation of Tetrahydrothiophenes via a Thia-Paternò-Büchi-Initiated Domino Photochemical Reaction
Kassir, Ahmad F.,Guillot, Régis,Scherrmann, Marie-Christine,Boddaert, Thomas,Aitken, David J.
supporting information, p. 8522 - 8527 (2020/11/12)
We have established photochemical access to thietane or tetrahydrothiophene compounds from thiobenzophenone derivatives and acrylonitrile, wherein the product selectivity is controlled by a simple adjustment of the reagent concentration in solution. Small libraries of five-membered ring sulfur-containing compounds were prepared through a thia-Paternò-Büchi reaction, followed by a previously unknown regioselective photochemical ring enlargement reaction in a domino process or a stepwise fashion. A mechanism is proposed to rationalize this ring enlargement reaction via a carbene species provided from photoexcited thiocarbonyl compounds.
Expeditious microwave-assisted thionation with the system PSCl 3/H2O/Et3N under solvent-free condition
Pathak, Uma,Pandey, Lokesh Kumar,Tank, Rekha
, p. 2890 - 2893 (2008/09/19)
(Chemical Equation Presented) A novel thionation protocol for carbonyl compounds, with the system PSCl3/H2O/Et3N has been discovered. Clean, rapid, and efficient synthesis of a variety of thiocarbonyl compounds such as thioamides, thiolactams, thioketones, thioxanthones, and thioacridone can be achieved through this simple and convenient method under solventless condition with microwave irradiation.
A new, efficient and simple method for the thionation of ketones to thioketones using P4S10/Al2O3
Polshettiwar, Vivek,Kaushik
, p. 6255 - 6257 (2007/10/03)
A simple, efficient and new method has been developed for the synthesis of thioketones by thionation of ketones using P4S10/Al 2O3 in acetonitrile. It has been found that the P 4S10/Al2O3 combination provides a simple and convenient method for the synthesis of thioketones.
Stereochemistry of the [4 + 2] cycloaddition of diarylselenoketones with conjugated dienes
Wilker, Stefanie,Erker, Gerhard
, p. 10922 - 10930 (2007/10/03)
The ylides Ph3P=CAr1Ar2 1a-g (Ar = C6H5, p-C6H4Cl, p-C6H4F, m-C6H4CF3, p-C6H4OCH3, p-C6H4-CH3) were treated with elemental selenium (～80°C) to give the corresponding selenoketones Se=CAr1Ar2 2 by Staudinger-chalcogenation. Their reaction with trans,trans-2,4-hexadiene proceeds completely stereospecifically to yield the 2,2-diaryl-3,6-dihydro-cis-3,6-dimethyl-2H-selenapyrans 3. In contrast, the reactions of the selenoketones 2 with cis,trans-2,4-hexadiene proceeds stereoselectively, also giving the dihydro-cis-dimethyl-2H-selenapyrans 3 as the major products, now admixed with small amounts of the dihydro-trans-dimethyl-2H-selenapyran isomers 4. The [4 + 2] cycloaddition of 2 with cis,trans-2,4-hexadiene proceeds stereospecifically, however, when carried out at a pressure of 12 kbar, now yielding 4 as the major products along with the corresponding tetraarylethenes 8. Along with the results of additional mechanistic studies (determination of solvent and substituent effects) it can be concluded that diarylselenoketones are likely to react by means of a concerted [4 + 2] cycloaddition with very reactive conjugated dienes (such as trans,trans-2,4-hexadiene), whereas a stepwise mechanism, resulting in diene cis/trans-isomerization with subsequent mechanistic "leakage" to the concerted pathway, appears to be preferred when a much less reactive conjugated diene such as cis,trans-2,4-hexadiene is employed. The reaction of the corresponding diarylthioketones 5a-g with trans,trans- and cis,trans-2,4-hexadiene, respectively, shows an analogous behavior.
9-Fluorenyl 9-(p-Tolylsulfonyl)-9-fluorenyl Disulfide: The Unexpected Product of the Reaction of 9-Bromofluorene and Potassium p-Toluenethiosulfate and the Mechanism of Its Formation
Kice, John L.,Kutateladze, Tatiana G.,Kupczyk-Subotkowska, Lidia
, p. 6151 - 6155 (2007/10/02)
Reaction of potassium p-toluenethiosulfonate with 9-bromofluorene leads, not to the expected 9-fluorenyl p-toluenethiosulfonate (3), but rather to a product shown to be 9-fluorenyl 9-(p-tolylsulfonyl)-9-fluorenyl disulfide (7, R = 9-fluorenyl) (eq 11).Thi
Elimination Reactions of Alkanesulfenyl Derivatives: Effect of Structure on Reactivity in Thioketone-Forming Eliminations of Diarylmethyl Thiosulfonates
Kice, John L.,Weclas, Ludmilla
, p. 32 - 39 (2007/10/02)
The reaction of a group of diarylmethyl arenethiosulfonates, ArAr'CHSSO2Ar'' (2), with (a) two alkoxide ions (i-PrO- and MeO-), (b) a series of secondary and tertiary amines of differing base strength, and (c) phenoxide ion has been examined.For each system both the overall rate of disappearance of 2 and the fraction (αelim) converted to thioketone were determined.Salient results are as follows: (1) The ρ values for thioketone-forming elimination of ArAr'CHSSO2C6H4CH3-p with either isopropoxide (+3.4) or piperidine (+3.5) are large and positive, while theρ value associated with variation of the substituent in Ar'' in the elimination of Ph2CHSSO2Ar'' with i-PrO- is quite modest (+1.3). (2) The Broensted β for the elimination reaction of p-nitrobenzhydryl p-toluenethiosulfonate with the series of amines is close to +1.0. (3) While plots of the elimination rate constant (kelim) vs. for any of the amine-induced elimination in amine-amineH+ buffers are linear, plots of kelim vs. -> for the phenoxide-induced elimination in PhO--PhOH buffers very pronounced downward curvature (Figure 4).These various results can be explained by assuming that the different eliminations proceed by different variants of an ElcB mechanism: for the elimination involving amines and 2 a reversible (ElcB)ion pr mechanism (eq 13) is suggested; in the elimination with phenoxide ion the reaction proceeds by an ordinary (ElcB)reversible mechanism (eq 9, ki>kii); in the elimination involving isopropoxide the mechanism becomes (ElcB)irreversible (eq 9, k-iii).Comparison of selected data on the rates of thioketone-forming eliminations of 2 with amines with data obtained previously (ref 6) on the rates of sulfene-forming eliminations of aralkyl α-disulfones with amines indicates that an arylalkanesulfonyl compound undergoes elimination approximately 300 million times faster than the equivalently substituted arylalkanesulfenyl derivative.
Photochemical Oxidation of Thioketones: Steric and Electronic Aspects
Ramnath, N.,Ramesh, V.,Ramamurthy, V.
, p. 214 - 222 (2007/10/02)
Oxidation of diaryl, aryl alkyl, and dialkyl thioketones by singlet oxygen generated via self-sensitization and other independent methods yielded the corresponding ketone and sulfine in varying amounts.A zwitterionic/diradical intermediate arising out of the primary interaction of singlet oxygen with the thiocarbonyl chromophore is believed to be the common intermediate for the ketone and sulfine.While closure of the zwitterion/diradical to give 1,2,3-dioxathietane would lead to the ketone, competing oxygen elimination is believed to lead to the sulfine.This partitioning is governed by steric and electronic factors operating on the zwitterionic/diradical intermediate.
