Y. Ren et al. / Tetrahedron Letters 51 (2010) 43–45
45
vated aryl bromides.14 The results were summarized in Table 3. In
general, many aryl bromides were smoothly converted into the
corresponding phenols. Moreover, the reactions were able to toler-
ate some functional groups such as hydroxyl, nitro, and methoxy
groups. Although nitryl group had an ability to activate aryl bro-
mides, our experimental result showed that 4-bromonitrobenzene
with a nitryl group could not be converted into 4-nitrophenol in
the case of no catalyst. Steric hindrance of the substituent in the
substrate had a significant effect on the reactions. For example,
bromobenzene gave the desired product in 82% yield, while 2,6-
di-tert-butyl-4-methylphenol with two tert-butyl groups in the
ortho-position of bromine gave a lower yield of 47% under the
3. (a) Hoarau, C.; Pettus, T. R. R. Synlett 2003, 127–137; (b) Shelby, Q.; Kataoka, N.;
Mann, G.; Hartwig, J. F. J. Am. Chem. Soc. 2000, 122, 10718–10719.
4. (a) Chen, G.; Chanb, A. S. C.; Kwongb, F. Y. Tetrahedron Lett. 2007, 48, 473–476;
(b) Anderson, K. W.; Ikawa, T.; Tundel, R. E.; Buchwald, S. L. J. Am. Chem. Soc.
2006, 128, 10694–10695; (c) Willis, M. C. Angew. Chem., Int. Ed. 2007, 46, 3402–
3404; (d) Maleczka, R. E.; Shi, F.; Holmes, D.; Smith, M. R., III J. Am. Chem. Soc.
2003, 125, 7792–7793.
5. (a) Kormos, C. M.; Leadbeater, N. E. Tetrahedron 2006, 62, 4728–4732; (b)
Weller, D. D.; Stirchak, E. P.; Yokoyama, A. J. Org. Chem. 1984, 49, 2061–2063;
(c) Rusonik, I.; Cohen, H.; Meyerstein, D. J. Chem. Soc., Dalton Trans. 2003, 2024–
2028; (d) Saphier, M.; Masarwa, A.; Cohen, H.; Meyerstein, D. Eur. J. Inorg. Chem.
2002, 1226–1234.
6. (a) Wu, X. F.; Bezier, D.; Darcela, C. Adv. Synth. Catal. 2009, 351, 367–370; (b)
Liu, Z. Q.; Wang, J. G.; Zhao, Y. K.; Zhoua, B. Adv. Synth. Catal. 2009, 351, 371–
374; (c) Bolm, C.; Legros, J.; Le Paih, J.; Zani, L. Chem. Rev. 2004, 104, 6217–
6254; (d) Gaillard, S.; Renaud, J. L. ChemSusChem. 2008, 1, 505–509; (e)
Enthaler, S.; Junge, K.; Beller, M. Angew. Chem., Int. Ed. 2008, 47, 3317–3321; (f)
Correa, A.; Mancheno, O. G.; Bolm, C. Chem. Soc. Rev. 2008, 37, 1108–1117; (g)
Sherry, B. D.; Furstner, A. Acc. Chem. Res. 2008, 41, 1500–1511; (h) Czaplik, W.
M.; Mayer, M.; Cvengros, J.; von Wangelin, A. J. ChemSusChem. 2009, 2, 396–
417.
7. (a) Ottesen, L. K.; Olsson, R. Org. Lett. 2006, 8, 1771–1773; (b) Hocek, M.; Cahiez,
G.; Habiak, V.; Duplais, C.; Moyeux, A. Angew. Chem., Int. Ed. 2007, 46, 4364–
4366; (c) Yamagami, T.; Shintani, R.; Shirakawa, E.; Hayashi, T. Org. Lett. 2007,
9, 1045–1048.
8. (a) Edulji, S. K.; Nguyen, S. T. Organometallics 2003, 22, 3374–3381; (b) Ohara,
H.; Itoh, T.; Nakamura, M.; Nakamura, E. Chem. Lett. 2001, 30, 624–625; (c)
Breschi, C.; Piparo, L.; Pertici, P.; Caporusso, A. M.; Vitulli, G. J. Organomet. Chem.
2000, 607, 57–63.
9. (a) Suzuki, K.; Oldenburg, P. D. Angew. Chem., Int. Ed. 2008, 47, 1887–1889; (b)
Taktak, S.; Ye, W.; Herrera, A. M.; Rybak-Akimova, E. V. Inorg. Chem. 2007, 46,
2929–2942; (c) Gelalcha, F. G.; Bitterlich, B.; Anilkumar, G.; Tse, M. T.; Beller, M.
Angew. Chem., Int. Ed. 2007, 46, 7293–7296.
10. (a) Casey, C. P.; Guan, H. J. Am. Chem. Soc. 2009, 131, 2499–2507; (b) Enthaler,
S.; Hagemann, B.; Erre, G.; Junge, K.; Beller, M. Chem. Asian J. 2006, 1, 598–604;
(c) Casey, C. P.; Guan, H. J. Am. Chem. Soc. 2007, 129, 5816–5817.
11. (a) Ren, Y. L.; Wang, W.; Zhao, S.; Tian, X. Z.; Wang, J. J.; Yin, W. P.; Cheng, L.
Tetrahedron Lett. 2009, 50, 4595–4597; (b) Barbero, N.; Carril, M.; SanMartin,
R.; Domínguez, E. Tetrahedron 2008, 64, 7283–7288.
same conditions (Table 3, entries 1 and 6).
a-Bromonaphthalene
afforded the naphthol product in 93% yield, whereas b-bromo-
naphthalene gave a lower yield of 55% (Table 3, entries 10 and
11), which suggested that bromine in b-position of naphthalene
was more difficult to transform. The present method was also
applicable to the reactions of aryl iodides. As shown in Table 3 (en-
tries 13–16), several aryl iodides afforded the desired products in
high yields from 75% to 90%.
In conclusion, an iron-catalyzed method for the conversion of
unactivated aryl halides to phenols was developed with water as
the solvent. After the reaction conditions were examined, it was
found that DMEDA/FeCl3 was the optimal catalytic system. By
using the present method, a series of unactivated aryl bromides
and aryl iodides were converted into the corresponding phenols
in moderate to high yields.
Acknowledgments
12. Buchwald, S. L.; Bolm, C. Angew. Chem., Int. Ed. 2009, 48, 5586–5587.
13. Beletskaya, I. P.; Cheprakov, A. V. Coord. Chem. Rev. 2004, 248, 2337–2364.
14. General experimental procedure for Iron-catalyzed conversion of aryl halides to
phenols: FeCl3 (0.2 mmol, purchased from Aladdin Reagent Co., purity >98%, Cu
<10 ppm), ligand (1 mmol) and TBAF (1 mmol) were added to a 10 mL stainless
steel autoclave containing H2O (3 mL). After the mixture was stirred at room
temperature for 5 min to give a homogeneous solution, K3PO4ꢀ3H2O (2 mmol)
and aryl halide (1 mmol) were added. Subsequently, the sealed autoclave was
placed in a 180 °C oil bath stirred for 20 h (the pressure that created on the
sealed autoclave was about 0.7 MPa). The desired product was extracted with
3 ꢁ 5 mL of diethyl ether. Evaporation of the solvent was followed by the GC
analysis of the product. The product was purified by column chromatography.
All the products are known compounds and were identified by comparison of
their 1H NMR and 13C NMR data with the literature data.
The authors wish to thank the financial supports from the
National High Technology Research and Development Program of
China (863 Program, Grant No. 2007AA05Z454) and the Innovation
Scientists and Technicians Troop Construction Projects of Henan
Province (Grant No. 084200510015).
References and notes
1. Tyman, J. H. P. Synthetic and Natural Phenols; New York: Elsevier, 1996.
2. Fyfe, C. A.. In The Chemistry of the Hydroxyl Group; Patai, S., Ed.; Wiley
Interscience: New York, 1971; Vol. 1,.