Editing Ether (section)

==Reactions== <!-- This section is linked from [[Organic reaction]] -->
[[Image:Diethylether peroxide chemical structure.png|frame|Structure of the polymeric [[diethyl ether peroxide]]]]
The C-O bonds that comprise simple ethers are strong. They are unreactive toward all but the strongest bases. Although generally of low chemical [[reactivity (chemistry)|reactivity]], they are more reactive than [[alkanes]].

Specialized ethers such as [[epoxide]]s, [[ketal]]s, and [[acetal]]s are unrepresentative classes of ethers and are discussed in separate articles. Important reactions are listed below.<ref name=Ullmann>Wilhelm Heitmann, Günther Strehlke, Dieter Mayer "Ethers, Aliphatic" in ''Ullmann's Encyclopedia of Industrial Chemistry'' Wiley-VCH, Weinheim, 2002. {{doi|10.1002/14356007.a10_023}}</ref>

===Cleavage===
{{see also|Ether cleavage}}
Although ethers resist hydrolysis, they are cleaved by hydrobromic acid and [[hydroiodic acid]]. [[Hydrogen chloride]] cleaves ethers only slowly. Methyl ethers typically afford [[methyl halide]]s:
:ROCH<sub>3</sub> + HBr → CH<sub>3</sub>Br + ROH
These reactions proceed via [[onium compounds|onium]] intermediates, i.e. [RO(H)CH<sub>3</sub>]<sup>+</sup>Br<sup>−</sup>.

Some ethers undergo rapid cleavage with [[boron tribromide]] (even [[aluminium chloride]] is used in some cases) to give the alkyl bromide.<ref>{{OrgSynth|author = J. F. W. McOmie and D. E. West|title = 3,3′-Dihydroxylbiphenyl|collvol = 5|collvolpages = 412|year = 1973|prep = CV5P0412}}</ref> Depending on the substituents, some ethers can be cleaved with a variety of reagents, e.g. strong base.

Despite these difficulties the chemical [[pulp (paper)|paper pulping]] processes are based on cleavage of ether bonds in the [[lignin]].

===Peroxide formation===
When stored in the presence of air or oxygen, ethers tend to form [[Explosive material|explosive]] [[organic peroxide|peroxides]], such as [[diethyl ether hydroperoxide]]. The reaction is accelerated by light, metal catalysts, and [[aldehyde]]s. In addition to avoiding storage conditions likely to form peroxides, it is recommended, when an ether is used as a solvent, not to distill it to dryness, as any peroxides that may have formed, being less volatile than the original ether, will become concentrated in the last few drops of liquid. The presence of peroxide in old samples of ethers may be detected by shaking them with freshly prepared solution of a ferrous sulfate followed by addition of KSCN. Appearance of blood red color indicates presence of peroxides. The dangerous properties of ether peroxides are the reason that diethyl ether and other peroxide forming ethers like [[tetrahydrofuran]] (THF) or [[dimethoxyethane|ethylene glycol dimethyl ether]] (1,2-dimethoxyethane) are avoided in industrial processes.

=== Lewis bases ===
[[File:CSD CIF CANZOG10.png|thumb|right|172px|Structure of VCl3([[Tetrahydrofuran|thf]])3.<ref>{{cite journal|journal=Inorg. Chim. Acta |author=F.A.Cotton |author2=S.A.Duraj |author3=G.L.Powell |author4=W.J.Roth |year=1986|volume=113|page=81|title=Comparative Structural Studies of the First Row Early Transition Metal(III) Chloride Tetrahydrofuran Solvates|doi=10.1016/S0020-1693(00)86863-2}}</ref>{{legend|blue|[[Vanadium]], V}}{{legend|darkgreen|[[Chlorine]], Cl}}{{legend|grey|[[Carbon]], C}}{{legend|white|[[Hydrogen]], H}}{{legend|red|[[Nitrogen]], N}}]]

Ethers serve as [[Lewis base]]s. For instance, [[diethyl ether]] forms a [[Coordination complex|complex]] with [[boron trifluoride]], i.e. borane diethyl etherate ({{chem2|BF3*O(CH2CH3)2}}). Ethers also coordinate to the [[magnesium|Mg]] center in [[Grignard reagent]]s. [[Tetrahydrofuran]] is more basic than [[Open-chain compound|acyclic]] ethers. It forms with many [[transition metal ether complex|complex]]es.

===Alpha-halogenation===
This reactivity is similar to the tendency of ethers with [[alpha]] hydrogen atoms to form peroxides. Reaction with chlorine produces alpha-chloroethers.