Propargyl bromide, also known as 3-bromo-prop-1-yne, is an organic compound with the chemical formula HC≡CCH2Br. A colorless liquid, it is a halogenated organic compound consisting of propyne with a bromine substituent on the methyl group. It has a lachrymatory effect, like related compounds. The compound is used as a reagent in organic synthesis.
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| Names | |
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| Preferred IUPAC name
3-Bromoprop-1-yne | |
| Other names
3-Bromo-1-propyne
Bromopropyne 1-Brom-2-propin 1-Bromo-2-propyne gamma-Bromoallylene 2-Propynyl bromide Propargyl bromide Propynyl bromide | |
| Identifiers | |
3D model (JSmol)
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| ChemSpider | |
| ECHA InfoCard | 100.003.135 |
PubChem CID
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| C3H3Br | |
| Molar mass | 118.961 g·mol−1 |
| Appearance | colourless liquid |
| Density | 1.57 g/mL (20 °C)[1] |
| Melting point | −61.1 °C (−78.0 °F; 212.1 K)[1] |
| Boiling point | 89 °C (192 °F; 362 K)[1] |
| insoluble | |
| Solubility | Soluble in organic solvents |
| log P | 1.179 |
| Vapor pressure | 72 mbar (20 °C)[1] |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards
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Highly Flammable, Toxic, Corrosive |
| NFPA 704 (fire diamond) | |
| Flash point | 18 °C (64 °F; 291 K)[1] |
| 324 °C (615 °F; 597 K)[1] | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Applications and production
editPropargyl bromide can also be used as an intermediate for the synthesis of organic compounds, including agrochemicals and pharmaceuticals. In the 1960s, it was used in a soil fumigant called Trizone.[2]
Propargyl bromide may be produced by the treatment of propargyl alcohol with phosphorus tribromide.[3]
Reactions
editPropargyl bromide is an alkylating agent. With dimethylsulfide, it reacts to give the sulfonium salt:[4]
- HCCCH2Br + S(CH3)2 → [HCCCH2S(CH3)2]Br
It also alkylates even weakly basic amines such as aniline.[5]
Aldehydes react with propargyl bromide in a Barbier-type reaction to yield alkynyl alcohols:[6]
At low temperatures, upon treatment with magnesium, propargyl bromide gives the Grignard reagent formally derived from allenyl bromide, i.e., CH2=C=CHMgBr.[7]
Safety
editPropargyl bromide is a lachrymator and an alkylating agent.[8] This liquid acetylenic endothermic compound may be decomposed by mild shock, and when heated under confinement, it decomposes with explosive violence and may detonate. Addition of 20—30 wt% of toluene makes propargyl bromide insensitive in laboratory impact and confinement tests.[9]
See also
editReferences
edit- ^ a b c d e f Record in the GESTIS Substance Database of the Institute for Occupational Safety and Health
- ^ Franz Müller and Arnold P. Applebyki "Weed Control, 2. Individual Herbicides" in Ullmann's Encyclopedia of Industrial Chemistry, 2010, doi:10.1002/14356007.o28_o01
- ^ "Process for Producing Propargyl Bromide". Retrieved November 7, 2012.
- ^ P. D. Howes, C. J. M. Stirling (1973). "3-Acetyl-2,4-Dimethylfuran". Organic Syntheses. 53: 1. doi:10.15227/orgsyn.053.0001.
- ^ Yu Chen, Anton Dubrovskiy, Richard C. Larock (2012). "Synthesis of Quinolines by Electrophilic Cyclization of N-(2-Alkynyl)Anilines: 3-Iodo-4-Phenylquinoline". Organic Syntheses. 89: 294. doi:10.15227/orgsyn.089.0294.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Jõgi, Artur; Mäeorg, Uno (30 November 2001). "Zn Mediated Regioselective Barbier Reaction of Propargylic Bromides in THF/aq. NH
4Cl Solution". Molecules. 6 (12): 964–968. doi:10.3390/61200964. - ^ Henning Hopf, Ingrid Böhm, and Jürgen Kleinschroth (1990). "Diels-Alder Reaction of 1,2,4,5-Hexatetraene: Tetramethyl[2.2]paracyclophane-4,5,12,13-tetracarboxylate". Organic Syntheses. 60: 41
{{cite journal}}: CS1 maint: multiple names: authors list (link); Collected Volumes, vol. 7, p. 485. - ^ "3-Bromo-1-Propyne". Retrieved November 3, 2012.
- ^ Urben, P.G., ed. (2017). "C1". Bretherick's Handbook of Reactive Chemical Hazards. pp. 81–882. doi:10.1016/B978-0-08-100971-0.00055-X. ISBN 978-0-08-100971-0.