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• 499140-12-4 benzyl (2R,4S,5R)-4-methyl-5-phenyl-1,2,3-oxathiazolidine-2-oxide-3-carboxilate 
• 1774-36-3 bis(4-methoxyphenyl) sulfoxide 
• 557-18-6 diethylmagnesium 
• 696-63-9 4-Methoxybenzenethiol 
• 16411-17-9 (4-methoxyphenyl)(vinyl)sulfane 

Relevant academic research and scientific papers

Asymmetric Sulfinylations of N-Methylephedrine-Modified Tri- or Tetraalkyl Zincates by Symmetric Diaryl Sulfoxides

Diethylzinc was treated with 1 or 2 equiv. of AlkMgCl or PhMgBr (preferably) or with 1 equiv. of nBuLi (less efficiently) for forming species – plausibly zincates – which were sulfinylated by diaryl sulfoxides to give racemic alkyl aryl sulfoxides in yields reaching 100 %. Dialkylzinc reagents were also activated by treatments with 1 or 2 equiv. of an enantiomerically pure alkylmagnesium β-aminoalkoxide. This worked best when the alkoxide stemmed from a dialkylmagnesium reagent and an equimolar amount of N-methyl-(–)-ephedrine. This second activation mode allowed sulfinylations of what was originally the dialkylzinc reagent with diaryl sulfoxides. This generated alkyl aryl sulfoxides with enantiomeric ratios up to 93:7 in up to 100 % yield.

Hydrogenative Kinetic Resolution of Vinyl Sulfoxides

Enantiopure sulfoxides are valuable precursors of organosulfur compounds with broad application in organic and pharmaceutical chemistry. An unprecedented strategy for obtaining highly enantioenriched sulfoxides based on a hydrogenative kinetic resolution using Rh-complexes of phosphine-phosphite ligands as catalysts is reported. After optimization, highly efficient conditions for the kinetic resolution of racemic sulfoxides have been identified. This methodology has been applied to a set of racemic aralkyl or aryl vinyl sulfoxides and allowed the isolation of both recovered and reduced products in excellent yields and enantioselectivities (up to 99% and 97% ee, respectively; 16 examples).

Symmetric diarylsulfoxides as asymmetric sulfinylating reagents for dialkylmagnesium compounds

At -78 °C, primary dialkylmagnesium compounds reacted with diarylsulfoxides when 1.5 equiv of the dilithium salt of (S)-BINOL was added as a promotor. Alkyl aryl sulfoxides resulted in up to quantitative yield and with up to 97% ee. This demonstrates the feasibility of asymmetric sulfinylations by achiral sulfinylating agents (from the perspective of Alkyl2Mg) as well as the feasibility of asymmetric sulfoxide-magnesium exchanges (from the perspective of Ar2SO).

A General and Expeditious One-Pot Synthesis of Sulfoxides in High Optical Purity from Norephedrine-Derived Sulfamidites

A general and simple procedure for preparing any kind of enantiomerically enriched sulfoxide starting from norephedrine-derived N-benzyloxycarbonylsulfamidite 3a is reported. After one-pot reaction of 3a with RMgX, HBF4, and R'MgX, a variety of sulfoxides 6 are obtained in ee usually higher than 93% and isolated yields ranging between 50 and 78%. The obtained configuration is tunable by simply electing the order of the addition of the reagents.

SYNTHESIS AND ABSOLUTE CONFIGURATIONS OF OPTICALLY ACTIVE OXOSULFONIUM SALTS

The optically active arylethylmethyloxosulfonium perchlorates (2a-c) were prepared by the oxidation of the corresponding sulfonium salts (1a-c) with sodium perbenzoate.The absolute configurations of oxosulfonium salts were determined by converting them into aryl ethyl sulfoxides (3a-c).From the relationship of the absolute configurations of ethylmethylphenylsulfonium perchlorate (1a) and ethylmethylphenyloxosulfonium perchlorate (2a), it was found that the oxidation of sulfonium salt (+)-(S)-1a with sodium perbenzoate proceeded with retention of configuration around the sulfur atom to afford oxosulfonium salt (+)-(R)-2a.The circular dichroism (CD) spectra of optically active oxosulfonium perchlorates (2) with (+)-(R) configuration show a positive strong Cotton effect at ca. 230 nm and a positive weak one at ca. 260 nm.Whereas, the CD spectra of optically active oxosulfonium perchlorates (2) with (-)-S configuration show a negative strong Cotton effect at ca. 230 nm and a negative one at ca. 260 nm.