Fluoromethyl phenyl sulfones

Convenient syntheses of vinyl fluorides are of synthetic interest, fhe conjugate base of fluoromethyl phenyl sulfone reacts with carbonyl compounds to provide P-tluoro alcohols, which are used to prepare terminal vinyl fluorides [25] (equation 23) (Table 9) This reaction offers an alternative to the Winig reaction, which may be very sensitive to reaction conditions. 

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

B. Fluoromethyl phenyl sulfone (2). To a 3-L, three-necked, round-bottomed flask, equipped with an overhead stirrer, thermometer, and 1-L addition funnel with sidearm are added Oxone (221.0 g, 0.36 mol) (Note 9) and water (700 mL). The mixture is cooled to 5°C and a solution of the crude fluoromethyl phenyl sulfide (1) in methanol (700 mL) is placed in the addition funnel and added in a slow stream to the stirring slurry. After addition of the sulfide, the reaction mixture is stirred at room temperature for 4 hr, (Note 10) and the methanol is removed on a rotary evaporator at 40°C. The remaining solution is extracted with methylene chloride (2 x 500 mL). The combined organic layers are dried over magnesium sulfate, concentrated to ca. 150 mL, filtered through a plug of silica gel (230-400 mesh, 300 mL, 10 x 6.5 cm), and washed with an additional 500 mL of methylene chloride (Note 11). The colorless filtrate is concentrated and the resulting oil or solid is dried under vacuum (0.1 mm) at room temperature to provide 29 g of crude fluoromethyl phenyl sulfone (2) as a solid... 

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

Alternatively, the chloroform solution can be treated with 2 equiv of 3-chloroperbenzoic acid (MCPBA) to provide fluoromethyl phenyl sulfone (see reference 2). 

Fluoromethyl phenyl sulfone Sulfone, fluoromethyl phenyl (8) ... 

Addition a to a cyano group Benzyltriethylammonium chloride, 239 Nickel, 197 Addition a to halogen Diiodomethane-Samarium, 113 Fluoromethyl phenyl sulfone, 135 Tris(dimethylamino)sulfonium difluo-rotrimethylsilicate, 336 Addition a to oxygen... 

Fluoromethyl phenyl sulfone, 135 Methylthiomethyllithium, 192 Methyl (trifluoromethylsulfonyl) methyl sulfone, 193 Addition a to selenium Potassium permanganate, 258 Other functionalized carbon reagents Allyltriphenylsilane, 13 Dicarbonyl(nitrosyl)-triphenylphosphinecobalt, 101... 

Fluoromethyl phenyl sulfone, 135 Chlorohydrins Calcium borohydride, 62 Lithium, 157 Sodium nitrite, 282 Titanium(IV) chloride-1,8-Diazabi-cyclo[5.4.0]undecene-7, 309 Iodohydrins... 

N-Alkyl-N-fluoroarenesulfonamides, 8 Fluoromethyl phenyl sulfone, 135 Tetrabutylammonium dihydrogentri-... 

The reaction of fluoromethyl phenyl sulfone with diethyl chlorophosphate at room temperature requires the use of 2 eq of base ( -BuLi, LDA, LiHMDS) to give the lithium salt of diethyl 1-(phenylsulfonyl)-l-fluoromethylphosphonate, which can be hydrolyzed and isolated in 73% yield or reacted in situ with a large variety of carbonyl compounds to form the corresponding a-fluorovinyl phenyl sulfones in moderate to good yields (44-95%, Scheme 3.9). - These sulfones are readily converted into 1-fluoroalkenes via the corresponding (fluorovinyl)stannanes. ... 

REACTION OF SULFOXIDES WITH DIETHYLAMINOSULFUR TRIFLUORIDE PREPARATION OF FLUOROMETHYL PHENYL SULFONE,... 

Organic fluorine compounds and methods for their preparation are the central topic of the next four procedures. Much of the synthetic versatility of methyl phenyl sulfone is embodied in FLUOROMETHYL PHENYL SULFONE and the fluoro Pummerer reaction of methyl phenyl sulfoxide with DAST is a key step in its preparation. The utility of this fluoromethyl sulfone in the preparation of fluoroalkenes Is demonstrated in a companion procedure for Z-[2-(FLUOROMETHYLENE) CYCLOHEXYL]BENZENE, a procedure with several prominent stereoselective features. Geminal difluoroalkenes are featured in the following procedure. (3,3 DIFLUOROALLYL)TRIMETHYLSILANE is prepared by a method in which the radical addition of dibromodifluoromethane to alkenes and the selective reduction of a-bromoalkylsilanes are key steps. A procedure for nucleophilic introduction of the trifluoromethyl group completes this set. The key reagent, (TRIFLUOROMETHYL)-TRIMETHYLSILANE is obtained by reductive coupling of TMS chloride and bromotrifluoromethane. Liberation of a CF3- equivalent with fluoride ion in the presence of cyclohexanone affords 1-TRIFLUOROMETHYL-1-CYCLOHEXANOL. 

Fluoromethylenation.11 Methods for fluoromethylcnation of ketones result in mixtures of (K)- and (Z)-vinyl fluorides, which are difficult to separate. A selective route involves reaction of the ketone with the carbanion of l-fluoro-l-(phenylsulfonyl)methane-phosphonate, prepared from fluoromethyl phenyl sulfones and diethyl chlorophosphate. The reaction provides mixtures of (E)- and (Z)-fluorovinyl sulfones, which can be separated by flash chromatography. Those products cannot be reduced by AI(Hg), but on treatment with tributyltin hydride (A1BN), they are converted into (fluorovinyl)stannancs with retention. Dcstannylation to vinyl fluorides can be effected with sodium methoxide in methanol or with CsF in methanolic ammonia.14... 

Alonso DA, Fuensanta M, Najera C, Varea M. 3,5-Bis(tri-fluoromethyl)phenyl sulfones in the direct Julia-Kocienski olefination. J. Org. Chem. 2005 70(16) 6404-6416. 

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