[60839-94-3] · C7H7FS · Fluoromethyl Phenyl Sulfide · (MW 142.21)
Physical Data: bp 60 °C/0.3 mmHg; nD22 1.5415.
Solubility: sol CH2Cl2, CHCl3, MeOH.
Preparative Methods: there are several methods of preparation. The reaction of Chloromethyl Phenyl Sulfide with Potassium Fluoride and 18-Crown-6 gives fluoromethyl phenyl sulfide in good yield (eq 1).1c Alternatively, the compound can be prepared by reaction of methyl phenyl sulfoxide with N,N-Diethylaminosulfur Trifluoride (F3SNEt2, DAST) (eq 2),1d,2,3 or with DAST and Antimony(III) Chloride (eq 3).1e,f,4
Direct a-fluorination of methyl phenyl sulfides can be performed by using DAST, antimony(III) chloride (eq 4),1f N-fluoro-2,4,6-trimethylpyridinium triflate (eq 5),5 and Xenon(II) Fluoride.6 a-Fluorination of sulfides by an electrolytic process is also known. However, it has not been used widely in organic synthesis.7
Of the methods reported, the routes shown in eqs 1-4 are more often used synthetically. a-Monosubstituted fluoromethyl phenyl sulfides are prepared from the reaction of the corresponding thioacetals with Mercury(II) Fluoride (eq 6).8
Handling, Storage, and Precautions: the compound should be used as soon as possible after purification by distillation. Storing it at 5 °C overnight then warming it to room temperature causes polymerization. Handle in a fume hood.
Fluoromethyl phenyl sulfide can be oxidized to Fluoromethyl Phenyl Sulfoxide by N-Bromosuccinimide1c or one equivalent of m-Chloroperbenzoic Acid1d -f,3,4,8 (the latter method is the most convenient and most often employed) (eq 7).
Oxidation to Fluoromethyl Phenyl Sulfone is conveniently carried out by using two equivalents of m-chloroperbenzoic acid (eq 8).1d,e,f,2,4b,d
Vichai Reutrakul & Manat Pohmakotr
Mahidol University, Bangkok, Thailand