Phase-vanishing reactions that use fluorous media as a phase screen. Facile, controlled bromination of alkenes by dibromine and dealkylation of aromatic ethers by boron tribromide

Journal of the American Chemical Society

Volumn 124, Issue 44, 2002, Pages 12946-12947

  Ryu, Ilhyong ^a   Matsubara, Hiroshi ^a   Yasuda, Shinji ^a   Nakamura, Hiroyuki ^b   Curran, Dennis P ^b  

^a Osaka Prefecture University   (Japan)

^b UNIVERSITY OF PITTSBURGH   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALKENE; BORON DERIVATIVE; BROMINE DERIVATIVE; ETHER DERIVATIVE;

ARTICLE; BROMINATION; DEALKYLATION; PHASE TRANSITION; REACTION ANALYSIS; SOLUBILITY; SYNTHESIS;

ALKENES; ALKYLATION; BORON COMPOUNDS; BROMINE; ETHERS; FLUOROCARBONS; HYDROCARBONS, BROMINATED;

EID: 0037032214     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja027965y     Document Type: Article

References (16)

1. (a) Horváth, I. T. Acc. Chem. Res. 1998, 31, 641.
2. (b) Curran, D. P. Angew. Chem., Int. Ed. 1998, 37, 1175.
3. (c) Cornils, B. Angew. Chem., Int. Ed. Engl. 1997, 36, 2057.
4. (d) Kitazume, T. J. Fluorine Chem. 2000, 105, 265.
5. (e) Furin, G. G. Russ. Chem. Rev. 2000, 69, 491.
6. (f) Curran, D. P. In Stimulating Concepts in Chemistry; Vögtle, F., Stoddard, J. F., Shibasaki, M., Eds.; Wiley-VCH: New York, 2000.
7. Symposium-in-Print on fluorous chemistry. Gladysz, J.; Curran, D. P. Tetrahedron 2002, 58, 3823 and succeeding papers.
8. Nakamura, H.; Linclau, B.; Curran, D. P. J. Am. Chem. Soc. 2001, 123, 10119.
9. Luo, Z.; Swaleh, S. M.; Theil, F.; Curran, D. P. Org. Lett. 2002, 4, 2585.
10. For the previously established procedures of bromination of alkenes, see: (a) Org. Synth. Coll. 1941; Vol. 1, p 521.
11. (b) Org. Synth. Coll. 1943; Vol. 2, p 171.
12. For bromination in ionic liquids, see: Chiappe, C.; Capraro, D.; Conte, V.; Pieraccini, D. Org. Lett. 2001, 3, 1061.
13. The polybromination course is negligible in our system, which often becomes a problematic side reaction. For a related reference, see: MacMillen, D. W.; Grutzner, J. B. J. Org. Chem. 1994, 59, 4516.
14. Like all slow addition techniques (for example, syringe pump additions), the maximum benefits are reaped when the reaction is much faster than the transport as in the case of the present bromination. Because reagents have some solubility in the fluorous phase, the disappearance of the bottom phase may not strictly correspond to the end of the reaction even for fast reactions. Yet it is a good qualitative guide that the reaction is approaching completion.
15. (a) McOmie, J. F. W.; Watts, M. L.; West, D. E. Tetrahedron 1968, 24, 2289.
16. (b) Benton, F. L.; Dillon, T. E. J. Am. Chem. Soc. 1942, 64, 1128.