37605-46-2Relevant academic research and scientific papers
Exploiting Substrate Diversity for Preparing Synthetically Valuable Sulfoxides via Asymmetric Hydrogenative Kinetic Resolution
Fernández-Pérez, Héctor,Grabulosa, Arnald,Lao, Joan R.,Vidal-Ferran, Anton
, (2020/07/24)
A detailed study is disclosed on the Rh-mediated hydrogenative kinetic resolution of α,β-unsaturated sulfoxides with alkyl and aryl substituents at the α-, E- and Z-positions of the double bond. This stereoselective catalytic methodology has enabled the p
Generation of 1,2-oxathiolium ions from (arysulfonyl)- and (arylsulfinyl)allenes in Br?nsted acids. NMR and DFT study of these cations and their reactions
Lozovskiy, Stanislav V.,Ivanov, Alexander Yu.,Khoroshilova, Olesya V.,Vasilyev, Aleksander V.
, p. 2897 - 2906 (2018/12/13)
In strong Br?nsted acids (CF3SO3H, FSO3H, D2SO4), (arysulfonyl)allenes (ArSO2-CR1=C=CR2R3) and (arylsulfinyl)allenes (ArSO-CR1=C=CR2R3) undergo cyclization into the corresponding stable 1,2-oxathiolium ions, which were studied by means of NMR and DFT calculations. Quenching of solutions of these cations with low nucleophilic media, aqueous HCl, leads to their deprotonation with a stereoselective formation of (arysulfonyl)butadienes (for instance, ArSO2-CR1=C-C(Me)=CH2, for R2 = R3 = Me, yields of 87-98%). Reactions of (arysulfonyl)allenes in the system TfOH (0.1 equiv)-HFIP (hexafluoropropan-2-ol) followed by hydrolysis give rise to allyl alcohols (ArSO2-CR1=CH-C(OH)R2R3, yields of 78-99%). Reflux of solutions of (arysulfonyl)allenes in the presence of TfOH (1 equiv) in 1,2-dichlorobenzene leads to the cyclization into thiochromene 1,1-diox-ides in high yields. Under the action of TfOH or AlX3 (X = Cl, Br) followed by hydrolysis of reaction mixtures, (arylsulfinyl)allenes give allyl alcohols (ArSO2-CR1=CH-C(OH)R2R3). Plausible reaction mechanisms have been proposed for all studied reactions.
Highly regio- and stereoselective palladium(0)-catalyzed addition of organoboronic acids with 1,2-allenic sulfones, sulfoxides, or alkyl- or aryl-substituted allenes in the presence of acetic acid: An efficient synthesis of E-alkenes
Guo, Hao,Ma, Shengming
, p. 2731 - 2745 (2008/03/13)
Two sets of reaction conditions were established to enable the palladium(0)-catalyzed addition of organoboronic acids with 1,2-allenic sulfones, sulfoxides, or alkyl- or aryl-substituted allenes in the presence of acetic acid. This reaction provides a new
Highly regio- and stereoselective halohydroxylation reaction of 1,2-allenyl phenyl sulfoxides. Reaction scope, mechanism, and the corresponding Pd- or Ni-catalyzed selective coupling reactions
Ma, Shengming,Ren, Hongjun,Wei, Qi
, p. 4817 - 4830 (2007/10/03)
A highly regio- and stereoselective halohydroxylation of 1,2-allenyl sulfoxides with X+ and water was developed. The reaction shows E-stereoselectivity. In the iodohydroxylation reaction, I2 was used to introduce the iodine atom. For
(Nitroaryl)sulfinyl-Substituted Allenes. Novel and Convenient Propargyl Alcohol Synthons in 4 + 2 Cycloaddition Chemistry
Padwa, Albert,Bullock, William H.,Norman, Bryan H.,Perumattam, John
, p. 4252 - 4259 (2007/10/02)
(Nitroaryl)sulfinyl-substituted allenes are conveniently prepared by treating propargyl alcohol or methyl 3-hydroxy-2-butynoate with a (nitroaryl)sulfenyl chloride and triethylamine.These activated allenes undergo 4 + 2 cycloaddition across the C1C2 α-bond.The initially formed allylic sulfoxide readily undergoes a 2,3-sigmatropic rearrangement to produce a stable sulfenate ester that is easily cleaved with thiophilic reagents.The dienophilic reactivity of the (nitroaryl)sulfinyl-substituted allene is much greater than the corresponding propargyl alcohol, and the cycloaddition also proceeds with high regioselectivity.The Diels-Alder reaction of propadiene with Danishefsky's diene affords meta-substituted benzyl alcohols in high yield.Reaction of the more highly activated methyl 2--2,3-butadienoate with Danishefsky's diene followed by treatment of the resulting sulfenate ester with triethyl phosphite produces substituted phthalides in excellent yield.The (2,4-dinitrophenyl)sulfinyl-substituted allene was found to react smoothly with a variety of nitrones to give sulfenate esters of isoxazolidines.These allenyl sulfoxides correspond to formal equivalents of propargyl alcohol, which itself is too unreactive to undergo Diels-Alder chemistry or 1,3-dipolar cycloaddition with nitrones or nitrile oxides.
NEW TRANSFORMATIONS OF SUBSTITUED ALLENE SULPHOXIDES
Cutting, Ian,Parsons, Philip J.
, p. 4463 - 4464 (2007/10/02)
The preparation and reactions of trimethylsilyl substituted allene sulphoxides are described.Allenes (2) rearrange on warming to give α,β-unsaturated thiol esters.
