Of methyl phenyl sulfoxides

A suspension of the dipeptide (1) (1 mmol) in water (2 ml) was stirred together with racemic methyl phenyl sulfoxide (2 mmol) at room temperature for one day. The formed inclusion compound was collected by filtration and washed with water (20 ml) and dichloromethane (20 ml). From the inclusion compound, we recoverd the included methyl phenyl sulfoxide by extraction with dichloromethane to give (/ )-methyl phenyl sulfoxide. The dipeptide (1) remained as a solid. When the recovered dipeptide (1) was again subjected to the formation of inclusion compound with racemic methyl phenyl sulfoxide, (A1 (-methyl phenyl sulfoxide was obtained as summarized in Table 5. Thus, it was shown that the dipeptide (1) can be used repeatedly for enantiomeric separation of methyl phenyl sulfoxide. 

This (Sj-rich methyl phenyl sulfoxide was subjected to the inclusion with the enantiomer (1 ) as summarized in Scheme 1. In this procedure, (.S )-methyl phenyl sulfoxide was obtained with high enantioselectivity. It is noteworthy that racemic methyl phenyl sulfoxide can be recovered from the washings. Thus, two enantiomers of methyl phenyl sulfoxide can be obtained by the use of the dipeptide (1) and its enantiomer (1 ). It should be noted that the present procedure can be applicable to other alkyl phenyl sulfoxides. 

Figure 17. Separation of methyl phenyl sulfoxide using (/ )-phenylglycyl-(7 )-phenylglycine (1) and ( -phenylglycyl- -phenylglycine (1 ).

Akazome, M., Ueno, Y., Ooiso, H., and Ogura, K. (2000) Enantioselective Inclusion of Methyl Phenyl Sulfoxides and Benzyl Methyl Sulfoxides by (i )-Phenylglycyl-(i )-phenylglycine and the Crystal Structures of the Inclusion Cavities, J. Org. Chem. 65, 68-76. 

Bromomethyl phenyl sulfoxide, QHsSCHjBr. Mol. wt. 219.12, b.p. 113°/0-l mm. The compound is prepared by reaction of methyl phenyl sulfoxide with NBS-Bt2 in the presence of pyridine. ... 

To a solution of 6.2 g (0.05 mol) of methyl phenyl sulfide in 50 mL of 95% ethanol is added 54.8 (0.1 mol) of the supported oxidant in one portion at room temperature. The mixture is stirred vigorously until the sulfide has been completely consumed, as detected by gas-liquid chromatography with a 5% Carbowax 20 M (a polyethylene glycol compound) column (5 h). After filtration of the solid and removal of most of the ethanol by evaporation of the filtrate, 25 mL of dichloro-methane is added. The solution is dried with anhydrous sodium sulfate and evaporated to dryness to give 5.54 g (88%) of methyl phenyl sulfoxide, bp 98-102 °C at 1 mm of Hg. 

Treatment of methyl phenyl sulfoxide with diethylaminosulfur trifluoride (DAST), in the presence of antimony trichloride provides 159 in quantitative yield (66). The reaction proceeds in good yield with dialkyl sulfoxides and alkyl aryl sulfoxides (163). Reoxidation of the a-fluorosulfide (165) to the corresponding sulfoxide (161), followed by pyrolysis, provides a direct synthesis of fluoroolefins (65). The reaction is believed to proceed by a Pummerer-type mechanism (l.e., a fluoro-Pummerer reaction, Scheme 48). Similarly, Umemoto (67) reported that N-fluorocollidine (167) converted sulfides to ot-fluorosulfides (170) presumably via an S-fluorosulfonium cation species 168 (Scheme 49). The synthetically challenging fluorovinyl ether nucleosides (175) and (176) were prepared using the fluoro-Pummerer reaction (Scheme 50) (60) the (E)-isomer (175) could be isomerized to 176 under photolytic conditions. Finch and co-workers (69) converted 160 to the sulfoximine 178 and demonstrated the utility of this compound as a mild fluoromethylene synthon (Scheme 51). Base-catalyzed condensation 178 with a carbonyl compound gave 179 which afforded... 

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. 

Lithiation of Methyl Phenyl Sulfoxide with LDA and Subsequent Alkylation with Butyl Bromide... 

As with the smaller compounds, reliable computational descriptions of methyl phenyl sulfoxide excited states are not available. Ground state computations are easily accessible for molecules of this size. At the RHF/6-31G(d,p) level, the HOMO is 7t with regard to the SO bond but delocalized throughout the whole n-system. The next two descending orbitals are localized on the phenyl and SO, respectively. (The sulfur lone pair is the HOMO-2 when the valence bond orbitals are approximated by the Edmiston-Ruedenberg method.) While the LUMO is extensively delocalized, the LUMO-fl is entirely localized on the phenyl ring. 

Isoquinolinones could also be formed from the annulation reactions of o-substituted Af-benzoylated sulfoximine and diphenylacetylene via Ru(II)-catalyzed redox-neutral C-H bond functionalization (Eq. (7.42)) [52]. As a result, the formation of methyl phenyl sulfoxide was observed, and the methyl phenyl sulfoximine directing group can be regenerated. 

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