Print version Print setup

Bromination of an alcohol; 1,4-Dibromobut-2-yne

SyntheticPage 474
DOI: 10.1039/SP474
Submitted Dec 06, 2010, published Dec 06, 2010
Suzanne Elizabeth Howson (s.e.howson@warwick.ac.uk)
A contribution from Scott group, Warwick University


			Reaction Scheme: Bromination of an alcohol

Chemicals Used

2-Butyne-1,4-diol
Bromine
Triphenylphosphine (recrystallised from hexane before use)
Dry Acetonitrile (dried by heating to reflux for 3 d under dinitrogen over calcium hydride)
Diethylether

 

Procedure

Procedure

Triphenylphospine (6.25 g, 23.82 mmol, 2.05 eq.) was suspended in dry acetonitrile (20 ml) in a Schlenk and then cooled to 0°C using an ice-water bath. Bromine (1.2 ml, 3.71 g, 23.24 mmol, 2.00 eq.) was added dropwise using a syringe (after each drop the solution was allowed to return to colourless before the next drop was added). 2-Butyne-1,4-diol (1.00 g, 11.62 mmol, 1.00 eq.) was dissolved in dry acetonitrile (10 ml) and was slowly added to the reaction mixture (n.b. all solid triphenylphosphine is taken into solution at this point). The reaction was stirred overnight at ambient temperature under argon (n.b. as the reaction proceeds solid precipitates from the solution). The solvent was removed from the reaction mixture and the residue was taken up in diethylether (~150 ml). The solution was then filtered and the solvent was removed from the filtrate to leave the crude product as a yellow liquid. This crude product was purified by Kügelrohr distillation to give a clear liquid (bp 80°C under high vacuum). Purified yield = 1.64 g, 7.74 mmol, 67%.

Author's Comments

Data

1H NMR (400 MHz, 298 K, CDCl3) δH 3.95 (4H, s, CH2).
13C{1H} NMR (100 MHz, 298 K, CDCl3) δC 81.6 (C≡C), 13.8 (CH2).


Lead Reference

R. Machinek and W. Luttke, Synthesis, 1975, 4, 255-256

Other References

G. Blond, C. Bour, B. Salem and J. Suffert, Organic Letters, 2008, 10, 1075-1078 (compound 72)

Supplementary Information

1H NMR spectrum in CDCl3 (1HNMR1,4-Dibromobut-2-yne.jcamp)
13C NMR spectrum in CDCl3 (13CNMR1,4-Dibromobut-2-yne.jcamp)

This page has been viewed approximately 9589 times since records began.

Get structure file (.cdx, .sk2, .mol)

Keywords: alcohols, alkyl/alkenyl/aryl halides, alkynes, bromination, substitution

Post new comment
Loading ...