Fluoromethyl Phenyl Sulfide1

[60839-94-3]  · C7H7FS  · Fluoromethyl Phenyl Sulfide  · (MW 142.21)

(synthesis of a-fluoro substituted sulfoxides1 and sulfones1e,2)

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.

Oxidation to Sulfoxides.

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 Sulfones.

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

1. (a) Schlosser, M. T 1978, 34, 3. (b) Wilkinson, J. A. CRV 1992, 92, 505. (c) More, K. M.; Wemple, J. S 1977, 791. (d) McCarthy, J. R.; Peet, N. P.; LeTourneau, M. E.; Inbasekaran, M. JACS 1985, 107, 735. (e) Wnuk, S. F.; Robins, M. J. JOC 1990, 55, 4757. (f) Robins, M. J.; Wnuk, S. F. JOC 1993, 58, 3800.
2. Inbasekaran, M.; Peet, N. P.; McCarthy, J. R.; LeTourneau, M. E. CC 1985, 678.
3. (a) Boys, M. L.; Collington, E. W.; Finch, H.; Swanson, S.; Whitehead, J. F. TL 1988, 29, 3365. (b) Jarvi, E. T.; McCarthy, J. R.; Mehdi, S.; Matthews, D. P.; Edwards, M. L.; Prakash, N. J.; Bowlin, T. L.; Sunkara, P. S.; Bey, P. JMC 1991, 34, 647. (c) McCarthy, J. M.; Jarvi, E. T.; Mathews, D. P.; Edwards, M. L.; Prakash, N. J.; Bowlin, T. L.; Mehdi, S.; Sunkara, P. S.; Bey, P. JACS 1989, 111, 1127.
4. (a) Robbins, M. J.; Wnuk, S. F. TL 1988, 29, 5729. (b) McCarthy, J. R.; Matthews, D. P.; Edwards, M. L.; Stemerick, D. M.; Jarvi, E. T. TL 1990, 31, 5449. (c) Krishnan, G.; Sampson, P. TL 1990, 31, 5609. (d) Matthews, D. P.; McCarthy, J. R.; JOC 1990, 55, 2973. (e) Robins, M. J.; Wnuk, S. F.; Mullah, K. B.; Dalley, N. K. JOC 1991, 56, 6878.
5. Umemoto, T.; Tomizawa, G. BCJ 1986, 59, 3625.
6. (a) Marat, R. K.; Janzen, A. F. CJC 1977, 55, 3031. (b) Zupan, M. JFC 1976, 8, 305.
7. (a) Brigaud, T.; Laurent, E. TL 1990, 31, 2287. (b) Fuchigami, T.; Shimojo, M.; Konno, A.; Nakagawa, K. JOC 1990, 55, 6074.
8. Purrington, S. T.; Pittman, J. H. TL 1987, 28, 3901.

Vichai Reutrakul & Manat Pohmakotr

Mahidol University, Bangkok, Thailand

Copyright 1995-2000 by John Wiley & Sons, Ltd. All rights reserved.