2-Bromopropane

Chemical compound

2-Bromopropane, also known as isopropyl bromide and 2-propyl bromide, is the halogenated hydrocarbon with the formula CH₃CHBrCH₃. It is a colorless liquid. It is used for introducing the isopropyl functional group in organic synthesis. 2-Bromopropane is prepared by heating isopropanol with hydrobromic acid.^[3]

Preparation

2-Bromopropane is commercially available. It may be prepared in the ordinary manner of alkyl bromides, by reacting isopropanol with phosphorus and bromine,^[4] or with phosphorus tribromide.^[5]

Safety

Short-chain alkyl halides are often carcinogenic.

The bromine atom is at the secondary position, which allows the molecule to undergo dehydrohalogenation easily to give propene, which escapes as a gas and can rupture closed reaction vessels. When this reagent is used in base catalyzed reactions, potassium carbonate should be used in place of sodium or potassium hydroxide.

Further reading

• Max Gergel, “Excuse Me Sir, Would You Like to Buy a Kilo of Isopropyl Bromide?” Pierce Chemical Co. (1979). (story of start-up chemical company).

References

1. Armarego, Wilfred L.F.; Li Lin Chai, Christina (2013). Purification of laboratory chemicals (7th ed.). Butterworth-Heinemann. p. 176. ISBN 9780123821621.
2. "2-bromopropane - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 27 March 2005. Identification. Retrieved 15 June 2012.
3. "Monograph 6526". Merck Index of Chemicals and Drugs.
4. Oliver Kamm and C. S. Marvel (1941). "Alkyl and alkylene bromides". Organic Syntheses; Collected Volumes, vol. 1, p. 25.
5. C. R. Noller and R. Dinsmore (1943). "Isobutyl bromide". Organic Syntheses; Collected Volumes, vol. 2, p. 358.