Phenyl sulfides, functionalized

Both the second and third processes in Scheme 13 can also be used for the functionalization of a-silylated alkyl phenyl sulfides [74] when oxidizing the latter in the presence of primary alcohols. First, the cleavage of the C—Si bond (equivalent to deprotonation) and then that of the S—C bond occurs to give... 

Phenyl vinyl sulfide possesses a number of synthetically useful attributes. It participates as an electron-rich alkene in 1 +2,2 2+2,3 3+2,4 and 4+25 cycloaddition reactions. Deprotonation of phenyl vinyl sulfide with strong base affords an a-metallated sulfide that reacts with electrophiles.6 The metallation-electrophile sequence and the cycloaddition reactions afford products amenable to further synthetic manipulation via the sulfide functionality. Furthermore, phenyl vinyl sulfide is a convenient precursor to the synthetically useful phenyl vinyl sulfoxide and phenyl vinyl sulfone.7... 

Harada, T., Oku, A., and Wada, 1. 1987. Enantiodifferentiating functionalization of 2-substituted 1,3-propanediols via chiral spiro ketal two methods for the preparation of (5)-2,3-dimethylbutyl phenyl sulfides. Tetrahedron Letters, 28(36) 4181. ... 

Benzenesulfenyl chloride can convm unsaturated adds to lactones. The unsatuiated add (7) is treated with benzenesulfenyl chloride, followed by Raney nickel, to afford the 7-lactone (8) in excdlent overall yield (equation 5). Another acid (9) has been lactonized to produce the spiro-p-lactone (10) whidi rearranges on silica gel to 7-lactone (11 equation 6). 6-Lactones have been also prqrared using diis rq>-proach. An additional advantage of this approach is that the phenyl sulfide moiety can be manipulated into a variety of functional groups to facilitate cyclization. in suirunary, successfiil cyclization reactions... 

Symmetrical sulfides are obtained in 70-90% yields by refluxing aqueous alcoholic solutions of halides with sodium sulfide. The nonahydrate of sodiiun sulfide is a satisfactory reagent for the reac-tion. Tetramethylene and pentamethylene halides give cyclic sulfides, e.g., tetramethylene sulfide (tetrahydrothiophene) (64%). Halides containing several other important functional groups have been employed. Typical examples include methallyl chloride, and halides with hydroxyl, ethoxyl, carboxyl, and diethylamino groups in the beta position. A dry synthesis of phenyl sulfide from calcium oxide, sulfur, and chlorobenzene at 300° has been reported. ... 

Hydrogen peroxide attacks the sulfur atom in preference to the double bond in allyl phenyl sulfide and allyl benzyl sulfide to give allyl phenyl sulfoxide (64%) and allyl benzyl sulfone (85%), respectively. Olefinic sulfones may also be obtained by dehydrohalogenation of /3-haloalkyl sulfones prepared by this method. Oxidation of sulfides has been utilized in the preparation of sulfones containing other common functional groups such as the amide, tro, amino, and ester groups. 

Chlorosulfides are often used for vicinal functionalization of alkenes. Silyl enol ethers can react with a-chloromethyl phenyl sulfides (5) in the presence of ZnBr2 or TiCU to give the corresponding -keto sulfide, which could be easily transfonned into the a-methylene ketone via sulfide oxidation to sulfoxide, followed by pyrolytic elimination (Scheme 23). 

Quantum yields of acid, and iodobenzene or phenyl sulfide were measured by irradiating. 03 molar acetonitrile solutions of diphenyl iodonium hexafluoroarsenate and triphenyl sulfonium hexa-fluoroarsenate. Photosensitizers were included at identical optical density (1.0) at the wavelength of irradiation (366 nm). Relative polymerization rates were calculated as a function of the gelation time of a solution of 50% acetone, and 50% cycloaliphatic diepoxide resin ARALDITE CY-179 (v/v) containing the photosensitizer and onium salt as above. Experimental details were published previously.(8,15) IRGACURE and ARALDITE are registered trademarks of the Ciba-Geigy Corporation. 

Thiophene is generally considered the most aromatic of the five-membered heterocycles, hence its reluctance to function as a diene in cycloadditions. A detailed study of the reaction of thiophene with six common benzyne precursors showed that side reactions with intermediates en route to benzyne often dominate the reaction course. Best results were obtained with diphenyliodonium-2-carboxylate 294, which gave up to 30% yields of naphthalene, presumably mainly through intermediate 295. Other benzyne-derived products [benzo( )thiophene, 0.5% 2-phenylthiophene, trace diphenyl sulfide, trace 1- and 2-naphthyl phenyl sulfides, 9 and 6%, respectively o-(2-thienyl)biphenyl, 4%] bring the... 

Jacobsen and Katsuki have both reported the use ofmanganese(III) (salen) catalysts for sulfide oxidation. These catalysts can be effective for the enantiose-lective oxidation of several aryhnethylsulfides using iodosylbenzene as the stoichiometric oxidant. Additionally, titanium(salen) complexes function as efficient catalysts in this procedure, providing up to 94% ee in the oxidation of methyl phenyl sulfide using the more economical urea hydrogen peroxide as oxidant. ... 

Methods to synthesize benzothiophenes via electrophilic (iodo) cyclization were separately published by Flynn and Larock in 2001. " The reaction typically involves electrophilic addition to an alkynyl substituent of a phenyl sulfide or thiophenol in the presence of iodine. Subsequent nucleophilic attack of the sulfur establishes the 5-membered ring system.Loss of a proton produces the corresponding benzothiophene functionalized at the C3 position with iodine. The resulting 3-iodothiophene can then undergo further transformation as described in previous sections. 

Org Synth 4 33, 16 29, 17 32]. It also catalyses the addition of allyl phenyl sulfide to alkynes leading to 1,4-dienes. The reaction with acetylenes affords high yields, and in the presence of chiral phosphine li nds, with high stereoselectivity. The reaction tolerates a variety of functional groups pJua et al. Org Lett 9 263 2007], SUSPECTED CARCINOGEN... 

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