24
A. Y. Koposov, V. V. Zhdankin
SHORT PAPER
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Oxidation of Sulfides to Sulfoxides with Reagent 3 in MeCN;
General Procedure
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To a stirred mixture of reagent 3 (88.5 mg, 0.275 mmol) in MeCN
(6 mL) the appropriate sulfide (0.5 mmol) was added. The mixture
was refluxed until full consumption of the reagent (monitored by
TLC) was observed. Then the reaction mixture was concentrated in
vacuo and separated by column chromatography (EtOAc–hexanes,
1:2 followed by EtOAc) to afford analytically pure sulfoxide.
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Acknowledgment
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This work was supported by a research grant from the National In-
stitutes of Health (R15 GM065148–01) and by NSF-MRI award
CHE-0416157.
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References
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(1) (a) Block, E. Angew. Chem., Int. Ed. Engl. 1992, 31, 1135.
(b) Holland, H. L. Chem. Rev. 1988, 88, 473.
(2) (a) Hudlicky, M. Oxidations in Organic Chemistry;
Washington, DC: American Chemical Society, 1990.
(b) Procter, D. J. J. Chem. Soc., Perkin. Trans. 1 1999, 641.
(c) Madesclaire, M. Tetrahedron 1986, 42, 5459.
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(3) (a) Varvoglis, A. The Organic Chemistry of
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Polycoordinated Iodine; VCH Publishers Inc.: New York,
1992. (b) Varvoglis, A. Hypervalent Iodine in Organic
Synthesis; Academic Press: London, 1997. (c) Hypervalent
Iodine Chemistry, In Topics in Current Chemistry, Vol. 224;
Wirth, T., Ed.; Springer-Verlag: Berlin Heidelberg, 2003.
(d) Zhdankin, V. V.; Stang, P. J. Chem. Rev. 2002, 102,
2523. (e) Wirth, T.; Hirt, U. H. Synthesis 1999, 1271.
(4) (a) Tohma, H.; Takizawa, S.; Watanabe, H.; Kita, Y.
Tetrahedron Lett. 1998, 39, 4547. (b) Tohma, H.;
5
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Scheme 1
In conclusion, we have found that IBX-esters are conve-
nient hypervalent iodine reagents for clean and selective
oxidation of organic sulfides to sulfoxides. The reaction
proceeds without over-oxidation to sulfones and is com-
patible with the presence of the hydroxy group, double
bond, phenol ether, benzylic carbon, and various substi-
tuted phenyl rings in the molecule of sulfide.
Maegawa, T.; Kita, Y. ARKIVOC 2003, 6, 62. (c) Tohma,
H.; Takizawa, S.; Watanabe, H.; Fukuoka, Y.; Maegawa, T.;
Kita, Y. J. Org. Chem. 1999, 64, 3519. (d) Tohma, H.;
Takizawa, S.; Morioka, H.; Maegawa, T.; Kita, Y. Chem.
Pharm. Bull. 2000, 48, 445. (e) Shukla, V. G.; Salgaonkar,
P. D.; Akamanchi, K. G. J. Org. Chem. 2003, 68, 5422.
(f) Ochiai, M.; Nakanishi, A.; Ito, T. J. Org. Chem. 1997, 62,
4253. (g) Ray, D. G. III; Koser, G. F. J. Org. Chem. 1992,
57, 1607. (h) Koser, G. F.; Kokil, P. B.; Shah, M.
Preparation of Reagent 3
To a rigorously stirred suspension of the isopropyl ester of 2-iodo-
benzoic acid (1.45 g, 5 mmol) and sodium hypochlorite solution
(‘bleach’, 5% NaOCl, 15 mL), CH2Cl2 (20 mL) was added, fol-
lowed by an excess of dry ice in the course of 10 min. The reaction
mixture was stirred overnight and then the organic layer was sepa-
rated while the aqueous layer was extracted with CH2Cl2 (3 × 10
mL). The combined organic fractions were dried over anhyd
MgSO4, the solvent was evaporated in vacuo to afford 1.43 g (89%)
of product 3.
Tetrahedron Lett. 1987, 28, 5431. (i) Xia, M.; Chen, Z.
Synth. Commun. 1997, 27, 1315. (j) Ou, W.; Chen, Z. Synth.
Commun. 1999, 29, 4443. (k) Yang, R.; Dai, L. Synth.
Commun. 1994, 24, 2229. (l) Barton, D. H. R.; Godfrey, C.
R. A.; Morzycki, J. W.; Motherwell, W. B.; Stobie, A.
Tetrahedron Lett. 1982, 23, 957. (m) Barbieri, G.; Cinquini,
M.; Colorina, S.; Montanari, F. J. Chem. Soc., C 1968, 659.
(5) Zhdankin, V. V.; Litvinov, D. N.; Koposov, A. Y.; Luu, T.;
Ferguson, M. J.; McDonald, R.; Tykwinski, R. R. J. Chem.
Soc., Chem. Commun. 2004, 106.
Mp 156 °C (decomp.).
(6) (a) Kutchin, A. V.; Rubtsova, S. A.; Loginova, I. V. Izv.
Akad. Nauk Ser. Khim. 2001, 50, 413. (b) Ali, M. H.;
Stevens, W. C. Synthesis 1997, 764. (c) Batigalhia, F.;
Zaldini-Hernandes, M.; Ferreira, A. G.; Malvestiti, I.; Cass,
Q. B. Tetrahedron 2001, 57, 9669. (d) Yamamoto, T.;
Kakimoto, M.; Okawara, M. Bull. Chem. Soc. Jpn. 1979, 52,
841. (e) Yang, Y.; Szafraniec, L. L.; Beaudry, W. T. J. Org.
Chem. 1990, 55, 3664.
IR (KBr): 1673, 789, 743 cm–1.
1H NMR (CDCl3): d = 8.34 (d, J = 7.8 Hz, 1 H), 8.01 (d, J = 7.6 Hz,
1 H), 7.84 (t, J = 7.5 Hz, 1 H), 7.58 (t, J = 7.4 Hz, 1 H), 5.31 (m, 1
H) 1.35 (d, J = 6.2 Hz, 6 H).
13C NMR (CDCl3): d = 167.5, 149.6, 134.9, 131.8, 130.2, 126.8,
124.8, 71.9, 21.8.
Anal. Calcd for C10H11IO4: C, 37.29; H, 3.44; I, 39.40. Found: C,
37.21; H, 3.49; I, 39.36.
Synthesis 2005, No. 1, 22–24 © Thieme Stuttgart · New York