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DOI: 10.1055/s-2006-942527
Tetrabutylammonium Fluoride in Dimethyl Sulfoxide: A Reagent Combination for the Twofold Dehydrobromination of Vicinal Dibromides
Publication History
Publication Date:
25 July 2006 (online)
Abstract
Exhaustive dehydrobromination of vicinal dibromides contained in cyclic systems of different ring sizes and containing diverse types of functionalities occurred for a variety of substrates when heated with tetrabutylammonium fluoride in dimethyl sulfoxide.
Key words
fluoride ion - dehydrobromination - dimethyl sulfoxide - unsaturated heterocycles - valence isomerization
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14a
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References
Paquette, L. A.; Dura, R. D.; Fosnaugh, N.; Stepanian, M. submitted for publication.
18The reaction outcome of the dibromide in run 10 (Table [1] ) is exemplary for the following reagents and conditions: (i) DBU, MeCN, sealed tube, 110 °C, 48 h (42% yield); (ii) NaH, THF, r.t. (no reaction); (iii) NaH, THF, reflux (no reaction); (iv) 1 M TBAF in THF (no DMSO) (24% yield); (v) pyridine (neat), reflux (no reaction); (vi) DABCO, benzene, reflux (no reaction); (vii) DABCO, DMSO, reflux (no reaction).
19The removal of Bu4N+ is trivial: a solvent into which DMSO does not partition well, for example Et2O, needs to be used and the soln should be washed with aq NH4Cl soln.