Bromination of Isoquinoline, Quinoline, Quinazoline and Quinoxaline in Strong Acid

William Dalby Brown; Alex Haahr Gouliaev

doi:10.1055/s-2002-19314

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Synthesis 2002(1): 0083-0086
DOI: 10.1055/s-2002-19314

PAPER

Bromination of Isoquinoline, Quinoline, Quinazoline and Quinoxaline in Strong Acid

William Dalby Brown^a, Alex Haahr Gouliaev*^b
^a Department of Chemistry, University of Copenhagen, Copenhagen, 2100, Denmark
^b Nuevolution A/S, Copenhagen, 2100, Denmark
Fax: +4570200986; e-Mail: ahg@nuevolution.com;

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Publication History

Received 10 September 2001
Publication Date:
04 August 2004 (online)

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Abstract

Bromination of benzazines and benzodiazines most often gives a mixture of products. In this paper, we show that isoquinoline (1) may be regioselectively monobrominated in concentrated H₂SO₄ using NBS or in CF₃SO₃H using N,N’-dibromoisocyanuric acid (DBI) to give 5-bromoisoquinoline (2). The bromination was found to be highly sensitive to the choice of brominating agent, acid, temperature and concentration. Quinoline, quinazoline and quinoxaline may be brominated likewise, although with the strong regioselectivity reserved to isoquinoline.

Key words

bromination - electrophilic aromatic substitution - regioselective - benzazines - benzodiazines

References

1 Iddon B. Wakefield BJ. In Bromine Compounds Price D. Iddon B. Wakefield BJ. Elsevier; Amsterdam: 1988. p.181-251

Google Scholar
2 Encyclopedia of Reagents for Organic Synthesis Paquette LA. Wiley; Chichester: 1995.

Google Scholar
3 Duan J. Zhang LH. Dolbier WR. Synlett 1999, 1245

Article in Thieme Connect Google Scholar
4 Osborn AR. Schofield K. Short LN. J. Chem. Soc. 1956, 4191

Google Scholar
5 Gordon M. Pearson DE. J. Org. Chem. 1964, 29: 329

Google Scholar
6 Rey M. Vergnani T. Dreiding AS. Helv. Chim. Acta 1985, 68: 1828

Crossref Google Scholar
7 Dewar MJS. Maitlis PM. J. Chem. Soc. 1957, 2521

Google Scholar
8 Butler JL. Forrest LB. Gordon M. Trans. Ky. Acad. Sci. 1977, 38: 15

Google Scholar
9 Gottardi W. Monatsh. Chem. 1968, 99: 815

Crossref Google Scholar
10 Gottardi W. Monatsh. Chem. 1969, 100: 42

Google Scholar
11 Perrin DD. Armarego WLF. Purification of Laboratory Chemicals Pergamon; Oxford: 1988. 3rd ed.. p.105

Google Scholar
12 Tochilkin AI. Kovel’man IR. Prokof’ev EP. Gracheva IN. Levinskii MV. Chem. Heterocycl. Compd. (Engl.Transl.) 1988, 24: 892

Crossref Google Scholar
13 Kanbara T. Saito N. Yamamoto T. Kubota K. Macromol. 1991, 24: 5883

Crossref Google Scholar
14 Saito N. Kanbara T. Nakamura Y. Yamamoto T. Kubota K. Macromol. 1994, 27: 756

Crossref Google Scholar
15 Sidhu GS. Thyagarajan G. Rao N. Indian J. Chem. 1963, 1: 346

Google Scholar
16 Hollstein U. Krisov GE. Org. Magn. Reson. 1980, 14: 300

Crossref Google Scholar

17

This expected doublet of doublet was observed as a triplet with the given coupling constant.