Allyl chloride
Allyl chloride is the organic compound with the formula CH2=CHCH2Cl. This colorless liquid is insoluble in water but soluble in common organic solvents. It is mainly converted to epichlorohydrin, used in the production of plastics. It is a chlorinated derivative of propylene. It is an alkylating agent, which makes it both useful and hazardous to handle.<ref name=Ullmann/>
ProductionEdit
Laboratory scaleEdit
Allyl chloride was first produced in 1857 by Auguste Cahours and August Hofmann by reacting allyl alcohol with phosphorus trichloride.<ref>Hofmann. Augustus William and Cahours. Augustus (1857) "Researches on a new class of alcohols," Philosophical Transactions of the Royal Society of London, 147: 555–574 ; see pp. 558–559.</ref><ref name=Ullmann>Ludger Krähling, Jürgen Krey, Gerald Jakobson, Johann Grolig, Leopold Miksche “Allyl Compounds” in Ullmann's Encyclopedia of Industrial Chemistry Wiley-VCH, Weinheim, 2005. Published online: 15 June 2000.</ref> Modern preparation protocols economize this approach, replacing relatively expensive phosphorus trichloride with hydrochloric acid and a catalyst such as copper(I) chloride.<ref name=Vogel>Template:Cite book</ref>
Industrial scaleEdit
Allyl chloride is produced by the chlorination of propylene. At lower temperatures, the main product is 1,2-dichloropropane, but at 500 °C, allyl chloride predominates, being formed via a free radical reaction:
- CH3CH=CH2 + Cl2 → ClCH2CH=CH2 + HCl
An estimated 800,000 tonnes were produced this way in 1997.<ref name=Ullmann/>
Reactions and usesEdit
The great majority of allyl chloride is converted to epichlorohydrin.<ref name=Ullmann/> Other commercially significant derivatives include allyl alcohol, allylamine, allyl isothiocyanate (synthetic mustard oil),<ref name=Ullmann2>F. Romanowski, H. Klenk "Thiocyanates and Isothiocyanates, Organic" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH: Weinheim. {{#invoke:doi|main}}</ref> and 1-bromo-3-chloropropane.
As an alkylating agent, it is useful in the manufacture of pharmaceuticals and pesticides, such as mustard oil.
Illustrative reactionsEdit
Illustrative of its reactivity is its cyanation to allyl cyanide (CH2=CHCH2CN).<ref>Template:OrgSynth</ref> Being a reactive alkyl halide, it undergoes reductive coupling to give diallyl:<ref>Template:Cite journal</ref>
- 2 ClCH2CH=CH2 + Mg → (CH2)2(CH=CH2)2 + MgCl2
It undergoes oxidative addition to palladium(0) to give allylpalladium chloride dimer, (C3H5)2Pd2Cl2. Dehydrohalogenation gives cyclopropene.
SafetyEdit
Allyl chloride is highly toxic and flammable. Eye effects may be delayed and may lead to possible impairment of vision.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>
See alsoEdit
External linksEdit
- Template:ICSC
- Template:PGCH
- IARC Monograph *Allyl chloride.