Phenyl-2- sulfone synthesis

Preparation of Fluoromethyl Phenyl Sulfone, a Reagent for the Synthesis of Fluoro Olefins. 

REACTION OF SULFOXIDES WITH DIETHYLAMINOSULFUR TRIFLUORIDE PREPARATION OF FLUOROMETHYL PHENYL SULFONE, A REAGENT FOR THE SYNTHESIS OF FLUOROALKENES (Benzene, [(fluoromethyl)sulfonyl]-)... 

Alkylation of phenyl sulfones.1 A convergent synthesis in which two synthons become attached through a double bond depends on the a-alkylation of the anion of a phenyl sulfone followed by a / -elimination. The synthesis of retinoic acid (4) is typical of the process. Potassium r-butoxide is used as base the recommended solvent is THF/NMP = 50 10. 

Mixed homocuprates.7 Mixed cuprates (1) in which the nontransferable ligand is an a-sulfonyl carbanion are easily prepared from dimethyl sulfone or methyl phenyl sulfone (equation I), and are effective for conjugate addition to enones and for a synthesis of ketones from acid chlorides. 

Gin utilised the reduction of an alkyl phenyl sulfone in a synthesis of the anti-leukaemia natural product (-)-deoxyharringtonine 61 Treatment of complex sulfone 61 with SmI2-HMPA gave 62 in 74% yield (Scheme 4.51). 

The results can be rationalized as follows the first cyclization of substrate 68 gave a mixture of a-sulfonyl radical intermediates 71 and 72 (Scheme 19). These then underwent a second fully stereoselective cyclization to give the cis- and franr-fused bicyclic products 69 and 70, respectively, as single isomers. Such sequential transformations, in which two carbon-carbon bonds are formed in a single step, are attractive methods for enhancing the efficiency of organic synthesis. As y-hydroxy-a,P-unsaturated phenyl sulfones can be prepared in enantiomerically pure form,48 this procedure should be readily applied to the synthesis of enantiomerically pure bicyclic products. 

The alkylation of the a-lithio-a-(methylsulfanyl) phenyl sulfone derived from compound 411 with a chiral epoxide has been used for the synthesis of 2-deoxynucleosides626. In the case of the starting material 416, the epoxide 417 was employed as electrophile in... 

Our strategy for the Smij-promoted synthesis of l,2-cis-C-glycosides is illustrated in Figure 3. It was assumed that one-electron transfer to the LUMO of the aryl sulfone group in A would result in concomitant cleavage of the C1 -S bond liberating an anomeric radical intermediate, as previously observed in the reductive lithiation of glycosyl phenyl sulfones." If 5-exo cyclization onto the silicon-tethered alkene/alkyne is substantially favored over a second electron transfer from Smij, then the exocyclic carbon radical B would ultimately be formed. On the other hand, reduction of the Cl-radical by... 

An attractive flexibility in using anomeric phenyl sulfones is that a stereodivergent synthesis of C-glycosides is available by alkylation before the reductive desulfonylation event. Thus, a one-pot four-step sequence of sulfone deprotonation-electrophile quenching-reductive lithiation-methanol quenching on sulfone 14 provides stereoselectively P-C-glycosides 19 as shown with aldehyde 16 (Fig. 

Figure 15 Synthesis of soluble anthracene polymer by AICl3 mediated copolymerization of 4,4 -bis(2,6-dimethylphenoxy-4-phenyl)sulfone with methylene chloride. (From Ref. 40.)... 

The reaction of the stabilized carbanion derived from a-phenylselanylmethyl phenyl sulfone with an acylsilane allowed the synthesis of E/Z mixtures of... 

In strong bases such as the one provided by sodium hydride and dimethyl sulfoxide (DMSO)—namely, dimsyl sodium—one should expect the formation of carbanions at sites of acidic protons. Ketones are attractive as potential sources of carbanions. However, ketone I features two blocked a carbons, without protons. Conversely, the tosyl group is ill suited for carbanion stabilization. The last functionality one may appeal to is the phenyl sulfone substituent at the end of the jec-pentyl chain. Recent investigations have revealed their potential as carbanion precursors, adding an important feature to their considerable usefulness in organic synthesis That is, sulfones can be removed under such mild conditions that carbonyl groups are not affected, and unconstrained a-sulfonyl carbanions have the unusual quality of retaining the asymmetry of their precursors in a wide variety of experimental conditions. ... 

Beau, J M, Sinay, P, Preparation and reductive lithiation of 2-deoxy-D-glucopyranosyl phenyl sulfones a highly stereoselective route to C-glycosides, Tetrahedron Lett., 26, 6185-6188, 1985. Crich, D, Lim, L B L, Synthesis of 2-deoxy-(3-C-pyranosides by diastereoselective hydrogen-atom transfer. Tetrahedron Lett., 31, 1897-1900, 1990. 

Beau, J M, Sinay, P, D-Glycopyranosyl phenyl sulfones their use in a stereocontrolled synthesis of cA-2,6-disubstituted tetrahydropyrans ((3-D-C-glycosides), Tetrahedron Lett., 26, 6189-6192, 1985. Schmidt, R R, Preuss, R, Betz, R, Vinyl carbanions. 33. C-1 lithiation of C-2 activated glucals. Tetrahedron Lett., 28, 6591-6594, 1987. 

This method has also been applied to a high-yielding stereoselective synthesis of C-linked IV-acetylneuraminic acid (Neu5Ac)-containing disaccharides [92] starting from either the 2-p)ridyl (phenyl) sulfones 189 and 190 or the anomeric chloride 191 (O Scheme 40). 

Alkylation reactions of ot-metallo sulfones bearing another heteroatomic moiety at their a-site have been widely used in synthesis. These reactions include the alkylations of a-isocyanoalkyl sul-fones a-alkoxyalkyl sulfones (including 2-benzenesulfonyltetrahydropyrans ) a-haloalkyl or a-haloallyl sulfones, a-silylalkyl sulfones,a-sulfonylalkyP ° and a-sul-fonylalkenyl or a-triflylalkyP - sulfones. Among these compounds alkoxyalkyl phenyl sulfones (Scheme 75, entries a and and tosylmethyl isocyanide (TosMIC) have been used as... 

SYNTHESIS OF (-)-(E,S)-3-(BENZYLOXY)-1-BUTENYL PHENYL SULFONE VIA A HORNER-WADSWORTH-EMMONS REACTION OF (-)-[Pg.145]

SYNTHESIS OF <-)-(E,S)-3-(BENZYLOXY)-1-BUTENYL PHENYL SULFONE VIA A HORNER-WADSWORTHEMMONS REACTION OF (.).(S)-2-(BENZYLOXY)PROPANAL (Benzene, [[[1-methyl-3-(phenylsulfonyl)-2-propenyl]oxy]methyl]-, [S-(E)]-) from (Propanal, 2-(phenylmethoxy)-, (S)-)... 

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