Vinyl sulfides phenyl

As a continuation of these studies, Bauld recently reported evidence of a stepwise mechanism in the cation-radical Diels-Alder reaction of phenyl vinyl sulfide with cyclopentadiene [34, 35] (Scheme 1.6). 

Triphenylphosphine was obtained from Nakarai Chemicals, Japan. When the reaction is carried out without additional triphenylphosphine, the yield of coupling product may drop to 60-70% and the product is accompanied by the by-products, phenyl vinyl sulfide and 4-viny 1-1 -cyclohexene, derived from 3-hydride elimination. 

A. 1-Bromo-1-phgnylthioethene. A 300-mL, two-necked, round-bottomed flask is fitted with a magnetic stirring bar, pressure-equalizing dropping funnel, and a reflux condenser to which a nitrogen inlet tube and an oil bubbler are attached, and flushed with nitrogen (Note 1). In the flask are placed 13.6 g (100 mmol) of phenyl vinyl sulfide (Note 2) and 80 mL of ether (Note 3), which are then cooled to ca. -78°C with a dry ice-methanol bath. Bromine (16.0 g. 100 mmol) is added dropwise over 30 min to the... 

The preparation of phenyl vinyl sulfide is described Org. Synth., Coll. Vol. VII 1990, 453. The compound is also available from Aldrich Chemical Company, Inc. 

Phenyl vinyl sulfide is prepared from thiophenol and 1,2-dibromoethane according to the procedure described by Paquette and Carr see Org. Synth. 1985, 64, 157. An earlier, three-step synthesis employing 2-chloroethanol instead of 1,2-dibromoethane is available.2... 

Bromovinyl phenyl sulfide Benzene, [(l-bromoethenyl)thio]- (10) (80485-53-6) Phenyl vinyl sulfide Sulfide, phenyl vinyl (8) Benzene, (ethenylthio)- (9) (1822-73-7)... 

Kita has introduced a novel one-pot preparation of 5-methoxylated indoline 55 and indole 56 derivatives by intermolecular addition followed by cyclization between A-tosylaniline derivatives 53 and activated olefins 54 using phenyliodine(III) bis(trifluoroacetate) (FIFA) <99H511785>. In the reaction of 53 with phenyl vinyl sulfides, indoles were produced directly by the spontaneous elimination of thiophenol. 

S. Phenyl vinyl eulfone. In a 250-mL, three-necked, round-bottomed flask fitted with a magnetic stirrer, condenser, addition funnel, and thermometer is placed 19.7 g (0.145 mol) of phenyl vinyl sulfide dissolved in 70 mL of glacial acetic acid. Hydrogen peroxide (30%, 56 mL, 0.5 mol) is added slowly at such a rate to maintain a reaction temperature of 70°C (Note 7). The reaction mixture is heated at reflux for 20 min, cooled, and treated with ether (150 mL) and water (200 mL). The organic phase is separated, washed with water (50 mL) and brine (50 mL), and concentrated at 70°C/0.3 mm for 3 hr, to afford 18-19 g (74-78%) of phenyl vinyl sulfone as a colorless... 

C. Phenyl vinyl sulfoxide. A 500 mL, three-necked, round-bottomed flask equipped with a dropping funnel and magnetic stirrer is charged with 20 g (0.147 mol) of phenyl vinyl sulfide and 250 mL of dichloromethane. The solution is stirred and cooled to -78°C while a solution of m-chloroperbenzoic acid (25.4 g, 1.0 equiv) in 200 mL of dichloromethane is added dropwlse during a 30-min period. The mixture is stirred and warmed to room temperature for 1 hr 1n a water bath at 30°C. The mixture is then poured into 300 mL of saturated sodium bicarbonate solution, and the mixture is extracted with three 250-mL portions of dichloromethane. The combined organic extracts are washed with three 250-mL portions of water and dried over anhydrous magnesium sulfate. The solvent is removed by rotary evaporation and the residual liquid is distilled to afford 15-16 g (68-70 ) of phenyl vinyl sulfoxide as a colorless liquid, bp 98°C/0.6 mm (Notes 9 and 10). 

When stored at room temperature, phenyl vinyl sulfide becomes yellow-colored within 1 day and a black syrup after 1 week. This decomposition can he substantially retarded by storage under a nitrogen or argon atmosphere in a freezer. 

Thiiranes react with benzyne in an efficient synthesis of phenyl vinyl sulfides. The reaction is stereospecific, thus producing ds-(phenylthio)stilbene from cis-2,3-diphenylthiirane and trans-(phenylthio)stilbene from fra .v-2,3-diphenylthiirane (Scheme 24) (84TL2679). 

Phenyl vinyl sulfides undergo one-electron transfer reactions with oxygen to give reasonable yields of a-ketosulfides (equation 34)159. 

Tietze and Schuffenhauer explored the intermolecular hetero Diels-Alder reaction of ethyl vinyl ether and sulfinimine 204 and found that at high pressures (11 kbar) and long reaction times (48 h at room temperature), tetrahydropyridines 205 and 206 were obtained in 96% yield and in a ratio of 1.7 1.107 The exo-adducts were not observed. Phenyl vinyl sulfide reacts similarly, but simple alkenes failed. Theoretical calculations and the experimental results suggest that while the cycloaddition is concerted, it is highly asynchronous. 

The submitters report that use of less than this amount of DBU reduces the yield of phenyl vinyl sulfide. 

Phenyl vinyl sulfide prepared using this procedure is stable at room temperature under a nitrogen atmosphere for months. The submitters have kept samples for over nine months at ambient temperature without any visible degradation. 

This procedure was used by the submitters to prepare 97 kg of phenyl vinyl sulfide from 100 kg of diphenyl disulfide (78% yield). 

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... 

The procedure described here affords phenyl vinyl sulfide in a high yield using common reagents and mild conditions. The material obtained via this procedure is stable at room temperature under a nitrogen atmosphere for months. As indicated in Note 10, this process is readily scaled up. Other methods either afford lower yields,7 8 9 less stable product,7 or require more extreme conditions.10 11... 

Prior to submission of this manuscript a new, efficient synthesis of phenyl vinyl sulfide was published Brace, N. O. J. Org. Chem. 1993, 58, 4506. 

PhenyIthiovinyllithium, CH2=CSC6H5 (1), 8, 281. The anion can be obtained conveniently by reaction of phenyl vinyl sulfide in THF with n-butyllithium and TMEDA at -90 . 

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