Phenyl sulfone derivative

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... 

The active forms of vitamin D analogues (1-14) were synthesized by the coupling of the steroid moiety [20] with the corresponding phenyl sulfone derivatives [21] to constitute the side chain part followed by the UV irradiation of the provitamins and the subsequent thermal isomerization of the previtamin D derivatives [22], These active forms of vitamin D analogues were also prepared through the cyclovitamin D derivatives [23]. 

The phenyl sulfone derivatives having larger alkyl groups such as propyl and butyl groups were also synthesized in a similar manner. The phenyl sulfone derivatives described here are employed for the preparation of various types of natural steroids derivatives [27]. This will be reported later. 

The synthetic procedure developed for the preparation of active fonns of vitamin D analogues was applied to the synthesis of various natural steroids by the reaction of steroid moieties with phenyl sulfone derivatives described here. 

The supply of the authentic sample is important in the study of biosynthesis. We synthesized the intermediates of biosynthesis of ergosterol from lanosterol in yeast [66]. Treatment of methyl phenyl sulfone (79) with epoxy alcohol (80) afforded phenyl sulfone derivative (83) [67]. Coupling of 83 with C-22-iodide derivative (47),... 

De Feo reported chemistry students who developed UPPE while synthesizing 9-bromofluorene in the laboratory (De Feo 1966). Roed-Petersen reported of a 22-year-old chemistry student who developed UPPE on the exposed parts from a phenyl sulfone derivative which he was synthesizing. Patch test gave a strong positive reaction to the compound (Roed-Petersen... 

Cu(III)(peptide)], with [Cu(I)(dmp)2], where dmp is 2,9-dimethyl-1,10-phen-anthroline, are rapid, outer-sphere processes which show some adherence to Marcus behavior,although the [Cu(dmp)2] self-exchange rate appears to be very dependent on the cross reaction,a lower limit of 3 X 10" mol" liter s arising from the [Cu(III)(peptide)] reactions, while a value of 9 x 10 mol liter s" is obtained from reaction with [IrCle], both at 25°C and 0.10 M ionic strength.Reactions of the copper(I) complex of the sterically hindered phenyl sulfonate derivative of dmp, [Cu(dpmp)2], with [Cu(III) (peptide)] are complicated by limiting rate behavior which is ascribed to activation of the copper(III) complex [reaction (25)]... 

Scheme 1 Nature of the di-lithiated species in phenyl sulfone derivatives...

Dimetal derivatives 283 of alkyl and benzyl phenyl sulfones were found to react with aldehydes or ketones to give a, /J-unsaturated phenyl sulfones 284 in good yields366. 

The lithio-derivative derived from cyclohexyl phenyl sulfone underwent 1,2-addition to cyclohexenylideneacetaldehyde or cinnamaldehyde to give the corresponding / -hydroxysulfones387. Reactions of 2,2-dimethyl-4-lithio-1,3-oxathiane 3,3-dioxide 308... 

The cyclopropane cyclizations by elimination of triflinic acid (CF3S02H) are readily effected by basic treatment of triflones (trifluoromethyl alkyl sulfones) with activated /-protons (equations 46 and 47)39. The cyclopropane diesters 45 are formed on treatment of 44 with potassium hydride in DMSO or sodium methoxide in methanol (equation 48). In contrast, the monoester 46 failed to give the desired cyclopropane40. Addition of carbanions derived from /f, y-unsaturated phenyl sulfones to a, /i-unsaturated carboxylic esters and subsequent elimination of benzenesulfinate ion give cyclopropanes possessing the unsaturated side chain and the ester function in trans positions (equation 49)41. 

Pedersen and coworkers investigated the El mass spectra of several 2-hydroxyphenyl alkyl sulfones (39) and sulfoxides (Section II.B). The methyl derivative seemed to fragment only via sulfinate ester formation giving the primary product ions m/z 157 and 109 (equation 14). Obviously hydrogen bonding between the ortho hydroxyl and the sulfone sulfur makes the loss of CH3SO2 difficult in contrast to the situation in methyl phenyl sulfone. The sulfinate ester rearrangement is not important when R>Et in 39. 

Cyclopropyl sulfones were shown to be obtained either by cyclization of y-p-tosyloxy sulfones 232 with base or by treatment of phenylsulfonylacetonitrile 233a or ethyl phenyl sulfonyl acetate 233b with 1,2-dibromoethane in the presence of benzyltriethyl-ammonium chloride (BTEA) and alkali in good yields. Chang and Pinnick synthesized various cyclopropane derivatives 234 upon initial treatment of carbanions derived from cyclopropyl phenyl sulfone with either alkylating agents or a carbonyl compound and subsequent desulfonylation, as shown below. 

However, most asymmetric 1,3-dipolar cycloaddition reactions of nitrile oxides with alkenes are carried out without Lewis acids as catalysts using either chiral alkenes or chiral auxiliary compounds (with achiral alkenes). Diverse chiral alkenes are in use, such as camphor-derived chiral N-acryloylhydrazide (195), C2-symmetric l,3-diacryloyl-2,2-dimethyl-4,5-diphenylimidazolidine, chiral 3-acryloyl-2,2-dimethyl-4-phenyloxazolidine (196, 197), sugar-based ethenyl ethers (198), acrylic esters (199, 200), C-bonded vinyl-substituted sugar (201), chirally modified vinylboronic ester derived from D-( + )-mannitol (202), (l/ )-menthyl vinyl ether (203), chiral derivatives of vinylacetic acid (204), ( )-l-ethoxy-3-fluoroalkyl-3-hydroxy-4-(4-methylphenylsulfinyl)but-1 -enes (205), enantiopure Y-oxygenated-a,P-unsaturated phenyl sulfones (206), chiral (a-oxyallyl)silanes (207), and (S )-but-3-ene-1,2-diol derivatives (208). As a chiral auxiliary, diisopropyl (i ,i )-tartrate (209, 210) has been very popular. 

An efficient synthetic route to (10Z)- and (10 )-19-lluoro-la,25-dihydroxy vitamin D3 has been developed (488). The key feature of this pathway is the introduction of a 19-fluoromethylene group to a (5 )-19-nor-10-oxo-vitamin D derivative. The 10-oxo compound 445 has been obtained via a 1,3-dipolar cycloaddition reaction of (5 )-la,25-dihydroxyvitamin D with in situ generated nitrile oxide, followed by ring cleavage of the formed isoxazoline moiety with molybdenum hexacarbonyl. Conversion of the keto group of (5 )-19-nor-10-oxo-vitamin D to the E and Z fluoromethylene group has been achieved via a two-step sequence, involving a reaction of lithiofluoromethyl phenyl sulfone, followed by the reductive de-sulfonylation of the u-lluoro-j3-hydroxysulfone. The dye-sensitized photoisomerization of the (5 )-19-fluorovitamin D affords the desired (5Z)-19-fluorovitamin D derivatives, (10Z)- and (10 )-19-fluoro-la,25-dihydroxy-vitamin D3. 

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