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Chem. 1995, 60, 2254. (e) Baruah, M.; Boruah, A.; Prajapati, D.; Sandhu, J. S. Synlett 1996, 1193. Huang, Y.;
Zhang, Y.; Wang, Y. Tetrahedron Lett. 1997, 38, 1065. (f) Kabalka, G.; Li, G. Tetrahedron Lett. 1997, 38, 5777.
(
g) Hays, D. S.; Fu, G. C. J. Org. Chem. 1998, 63, 2796.
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9
. For example, see: Johnstone, R. A. W.; Wilby, A. H.; Entistle, I. D. Chem. Rev. 1985, 85, 129.
. For example, see: Greenspoon, N.; Keinan, E. J. Org. Chem. 1988, 53, 3723.
. For example, see: Rajagopal, S.; Spatola, A. F. J. Org. Chem. 1995, 56, 4481.
. Bae, J. W.; Cho, Y. J.; Lee, S. H.; Yoon, C. M. Tetrahedron Lett. 2000, 41, 175.
. Yasuhara, A.; Kasano, A.; Sakamoto, T. J. Org. Chem. 1999, 64, 2301.
. Moody, C. J.; Pitts, M. R. Synlett 1998, 1028.
. Banik, B. K.; Mukhopadhyay, C.; Venkatraman, M. S.; Becker, F. F. Tetrahedron Lett. 1998, 39, 7243.
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0. Boothroyd, S. R.; Kerr, M. A. Tetrahedron Lett. 1995, 36, 2411.
1. Kumbhar, P. S.; Sanchez-Valente, J.; Figueras, F. Tetrahedron Lett. 1998, 39, 2573.
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2. Fisher, B.; Sheihet, L. J. Org. Chem. 1998, 63, 393.
3. Suwinski, J.; Wagner, P.; Holt, E. M. Tetrahedron 1996, 52, 9541.
4. Becker, F. F.; Banik, B. K. Bioorg. Med. Chem. Lett. 1998, 8, 2877.
5. (a) Ghatak, A.; Becker, F. F.; Banik, B. K. Tetrahedron Lett. 2000, 41, 3793. (b) Banik, B. K., Zegrocka, O.;
Banik, I.; Hackfeld, L.; Becker, F. F. Tetrahedron Lett. 1999, 40, 6731
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6. For an example, see: Han, B. H.; Boudjouk, P. J. Org. Chem. 1982, 47, 5030.
7. A representative procedure is given below: To a solution of the nitro compound (0.5 mmol) in methanol (5 mL)
(for those compounds which are not completely soluble in methanol, a few drops of dichloromethane was added
to make it soluble), solid ammonium chloride (10.0 mmol) and samarium metal (2.2 mmol, 40 mesh) were added
and the reaction mixture was sonicated18 at room temperature for 10±20 min (Table 1). The reaction started
immediately as indicated by the evolution of gas, an increase in the internal temperature and by the change in the
color of the mixtures. After the reaction was over, as indicated by TLC, water (5 mL) was added and then it was
extracted with dichloromethane, dried over sodium sulfate and concentrated. The pure product was isolated by
®
ltration through a short column over silica gel using ethyl acetate and hexanes as the solvent. The reaction can be
carried out with 1±2 g nitro compound. All products have been characterized through a comparison of mp, TLC
and NMR with authentic compounds.
8. A Bransonic Model 2210R-DTH was used for sonication.
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