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In organic chemistry and biochemistry, an ether is functional group that may result from the condensation of alcohols.
ROH + HOR' --> ROR' + H2O alcohol alcohol etherThis direct reaction is not suitable in most synthetic pathways. There exist several milder methods to produce ethers. One method involves treatment of a parent alcohol (R-OH) with a strong base to form the alkoxide ion (R-O-) followed by addition of an appropriate aliphatic compound bearing a suitable leaving group (R-L). Suitable leaving groups (L) include Iodine, Bromine or Sulfonate esters. This is called Williamson ether synthesis.
Like esters, ethers are limited in their ability to form hydrogen bonds. They tend to be more hydrophobic than other, analogous condensation products (such as esters or amides). They are resistant to hydrolysis.
In addition to the generic meaning, the term "ether" also commonly refers to the specific compound diethyl ether, CH3CH2OCH2CH3, also known as ethoxyethane. Chemist Raymundus Lullis, discovered the compound in 1275. Its was first synthesized by Valerius Cordus in 1540. Crawford Williamson Long, M.D., was the first surgeon to use it as an anesthetic agent, on March 30, 1842. Its first use is normally associated with the Etherdome in Boston.
Ethers which have a CH group next to the oxygen form peroxides which are highly explosive. Due to this and the low ignition point of diethyl ether, diethyl ether is one of the risk factors in laboratories.
Despite their comparably attenuated reactivity, ethers can act as Lewis acids (see Acid-base reaction theories). For instance, diethyl ether forms a complex with boron compounds, such as boron trifluoride etherate, F3B:O(CH2CH3)2
Ethers can be named in two ways according to the IUPAC naming system. The first, used for simple ethers, simply lists the two groups attached to the ether in alphabetical order followed by the word "ether". Thus CH3-CH2-O-CH3 is ethyl methyl ether. When the ether is part of a more complex molecule, it is named as an alkoxy substituent, so -OCH3 would be considered a "methoxy-" group.