G. W. Kabalka, A. R. Mereddy / Tetrahedron Letters 45 (2004) 343–345
345
5. Pomilio, A. B.; Barolli, M. G. J. Label. Compd. Radio-
pharm. 1997, 39, 927.
The reaction of potassium alkyltrifluoroborates with
chloramine-T and sodium iodide was also investigated
and found to be less efficient. For example potassium
2-phenyl-1-ethyl- and cyclohexyltrifluoroborates react
withchloramine-T and sodium iodide to yield 30% of
the expected products after 24 h at reflux.
6. (a) Kabalka, G. W.; Gooch, E. E. J. Org. Chem. 1981, 46,
2582; (b) Kabalka, G. W.; Sastry, K. A. R.; Hsu, H. C.;
Hylarides, D. M. J. Org. Chem. 1981, 46, 3113; (c)
Kabalka, G. W.; Akula, M. R.; Zhang J. Nucl. Med. Biol.
2002, 29, 841.
7. (a) Vedejs, E.; Chapman, R. W.; Fields, S. C.; Lin, S.;
Schrimpf, M. R. J. Org. Chem. 1995, 60, 3020; (b) Vedejs,
E.; Fields, S. C.; Hayashi, R.; Hitchcock, R.; Powell, D.
R.; Schrimpf, M. R. J. Am. Chem. Soc. 1999, 121, 2460; (c)
Batey, R. A.; Quach, T. D. Tetrahedron Lett. 2001, 42,
9099; (d) Molander, G. A.; Ito, T. Org. Lett. 2001, 3, 393;
(e) Molander, G. A.; Biolatto, B. Org. Lett. 2002, 4, 1867;
(f) Pucheault, M.; Darses, S.; Genet, J.-P. Eur. J. Org.
Chem. 2002, 3552.
In conclusion, we report a convenient procedure for
preparing aryl iodides from potassium aryltrifluoro-
borates.
Acknowledgements
8. Bir, G.; Schachit, W.; Kaufmann, D. J. Organomet. Chem.
1990, 55, 1868.
We wish to thank the U.S. Department of Energy and
the Robert H. Cole Foundation for their support of this
research.
9. General procedure: To a solution of potassium aryltri-
fluoroborate (1.00 mmol) in 50% aqueous tetrahydrofuran
(5 mL) contained in a round bottomed flask (which
was shielded from light), chloramine-T (1.00 mmol) was
added followed by sodium iodide (1.05 mmol). The
resulting mixture was stirred at room temperature for
the required length of time (Table 2). After the reaction
was complete, 10% aqueous sodium thiosulfate (2 mL) was
added to decompose excess iodine. The mixture was
extracted withetyhl acetate (3 · 25 mL), the combined
organic extracts washed with water (20 mL), brine
(20 mL), dried over anhydrous sodium sulfate, and con-
centrated under reduced pressure. The product was
purified by column chromatography over silica gel (100–
200 mesh) using 98:2 petroleum ether/ethyl acetate. The
products were identified by comparison of physical and
spectral properties withliterature values.
References and Notes
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