43161-07-5Relevant academic research and scientific papers
Sulfoxide synthesis from sulfinate esters under Pummerer-like conditions
Kobayashi, Akihiro,Matsuzawa, Tsubasa,Hosoya, Takamitsu,Yoshida, Suguru
supporting information, p. 5429 - 5432 (2020/06/04)
A facile synthetic method for the preparation of allyl sulfoxides byS-allylation of sulfinate esters proceeds through sulfonium intermediates without [3,3]-sigmatropic rearrangement and further Pummerer-type reactions of the resulting allyl sulfoxides. On the basis of the plausible reaction mechanism involving sulfonium salt intermediates,S-alkynylation andS-arylation were also accomplished.
Synthesis of allyl sulfoxides from allylsilanes via silyl sulfinates
Stikute, Agnese,Peipi??, Vilnis,Turks, Maris
supporting information, p. 4578 - 4581 (2015/07/08)
Allylsilanes underwent sila-ene reaction with sulfur dioxide in the presence of Lewis acid catalysts. The obtained Vogel's silyl sulfinates were found to act as sulfinyl transfer agents in reactions with aryl, heteroaryl, alkyl, and allyl Grignard reagents proceeding with the expulsion of the trialkylsilyloxy group to give allyl sulfoxides in up to 83% yield. The nucleophilic attack of Grignard reagents was accelerated in toluene and in the presence of LiCl or ZnCl2 as Lewis acidic additives. The developed method allows the transformation of allylsilanes into allyl sulfoxides.
Highly chemoselective synthesis of aryl allylic sulfoxides through calcium hypobromite oxidation of aryl allylic sulfides
Pace, Vittorio,Castoldi, Laura,Holzer, Wolfgang
supporting information; experimental part, p. 967 - 972 (2012/03/11)
A highly chemoselective oxidation of widely substituted aryl allylic sulfides, prepared by allylation of arylthioethers with KF-Celite, to the corresponding aryl allylic sulfoxide was achieved by employing calcium hypobromite. Neither over-oxidation to sulfones nor halogenation of the aromatic rings was observed. The protocol may be successfully applied for the oxidation of substituted allylic systems (i.e., 2-haloallyl) that per se could interact with the oxidizing agent.
Additive Pummerer reactions of vinylic sulfoxides. Synthesis of γ-hydroxy-α,β-unsaturated esters, α-hydroxyketones, and 2-phenylsulfenyl aldehydes and primary alcohols
Craig, Donald,Daniels, Kevin,MacKenzie, A. Roderick
, p. 11263 - 11304 (2007/10/02)
Treatment of β-monosubstituted vinylic sulfoxides 1 with trifluoroacetic anhydride in dichloromethane gave excellent yields of 1,2-bis(trifluoroacetoxy)thioethers 6. Mildly basic methanolysis of 2-alkyl-substituted 6 gave α-hydroxyaldehydes 11 as monomer-dimer mixtures; similar treatment of the 2-aryl analogues afforded aryl (hydroxymethyl) ketones 12. Compounds 11 underwent Wittig reactions with methoxycarbonylmethylenetriphenylphosphorane to give high yields of γ-hydroxy-α,β-unsaturated esters 13, predominantly as the E-isomers. β-Monosubstituted vinylic sulfoxides 1 possessing a β-aryl group, and β-disubstituted vinylic sulfoxides 3 reacted with trifluoromethanesulfonic anhydride-sodium acetate in acetic anhydride to give 2-(phenylsulfenyl) acylals 14. These gave 2-phenylsulfenyl aldehydes 15 upon basic methanolysis, and the corresponding primary alcohols 16 on reduction with sodium borohydride. Reaction of both geometric isomers of enantiomerically pure vinylic sulfoxide 1o with TFAA gave racemic 6o as a mixture of diastereomers. Reaction of optically pure (E)- and (Z)-1p with trifluoromethanesulfonic anhydride-sodium acetate in acetic anhydride gave acylal 19 in 10.5 and 23% e.e., respectively.
Aprotic Conjugate Addition of Allyllithium Reagents Bearing Polar Groups to Cyclic Enones. 2. 2-Alkyl-, 2,3-Dialkyl-, and 1,3-Dialkylallyl Systems
Haynes, Richard K.,Katsifis, Andrew G.,Vonwiller, Simone C.,Hambley, Trevor W.
, p. 5423 - 5433 (2007/10/02)
As an extension of the work carried out on the conjugate addition reactions of lithiated 3-alkylallylic sulfoxides, phosphine oxides, and phosphonates to cyclic enones, the effects of placing methyl groups at C2, at C2 and C3, and at C1 and C3 of the allyl system and of placing the allyl system within a five-membered ring are examined.From the lithiated 2-methallyl and (E)-2-methylbut-2-enyl ("tiglyl") sulfoxides, mixtures of diastereomeric (E)- and (Z)-vinilyc sulfoxides resulting from conjugate addition to cyclopentenone are obtained.The proportion of Z diastereomers formed increases with the reaction temperature.In contrast, lithiated (Z)-2-methylbut-2-enyl ("angelyl") sulfoxides and the tiglyl and angelyl phosphine oxides undergo highly diastereoselective conjugate addition to give (E)-vinylic products.Lithiated 1,3-dimethylbut-2-enyl sulfoxides undergo stereoconvergent reactions in that the starting sulfoxides, as mixtures of diastereomers, are converted into vinylic sulfoxides, which are obtained as single diastereomers.The individual diastereomers of tert-butyl cyclopentenyl sulfoxide upon lithiation undergo conjugate addition with cyclopentenone to give the same vinylic sulfoxide.A sulfenate ester also results from carbonyl addition.The structures of the diastereomers have been established by high-field (1)H NMR spectoscopy, by chemical correlation, and in two cases by X-ray crystallographic studies.The destabilizing influence of the methyl groups on the normal "trans-fused chair-chair"-like extended transition state causing access to "cis-fused boat-boat"-like, "cis-fused chair-chair"-like, and "trans-fused boat-chair"-like transition states involving planar lithiated reagents provides a rationale for the results.The temperature dependence of some of these reactions, and simple quenching experiments in which the individual lithiated diasteromers of the cyclopentenyl sulfoxide are converted into a single diasteromer, provide evidence for planar lithiated sulfoxides.
THERMAL (1,3)-ALLYLIC REARRANGEMENTS IN SULFOXIDES AND SULFONES
Baechler, Raymond D.,Bentley, Pamela,Deuring, Lisa,Fisk, Susan
, p. 2269 - 2272 (2007/10/02)
Rates and activation parameters for thermal (1,3)-allylic rearrangement have been determined for the systems β-methylallyl phenyl sulfoxide (2) and the corresponding sulfone (3), with evidence presented for a dissociative reaction mechanism.
Asymmetric Induction in the Additions of Anions of Allylic Sulfoxides to Benzaldehyde
Antonjuk, David J.,Ridley, Damon D.,Smal, Mary A.
, p. 2635 - 2651 (2007/10/02)
Addition reactions of anions of aryl allyl sulfoxides to benzaldehyde proceed readily in moderate yields and afford mixtures of products resulting from α- and γ-attack on the allyl anion.The γ-products all possess the (E)-configuration around the double bond, and asymmetric induction occurs in the addition to the extent that the major/minor diastereomer ratio exceeds 2:1, generally.Electronic factors are believed to be responsible for this "remote" asymmetric induction.Mixtures of all four possible diastereomers are observed in the products from α-attack and evidence is presented which suggests that the ratios of these products are as a result of epimerization of two of the chiral centres by sigmatropic rearrangement.
