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This article is about a general class of organic compounds. For other uses, see Aether.
The general structure for an ether
The general structure for an ether

Ether is a class of organic compounds which contain an ether group — an oxygen atom connected to two (substituted) alkyl or aryl groups — of general formula R–O–R'. An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. In Organic chemistry, functional groups are specific groups of Atoms within Molecules that are responsible for the characteristic Chemical reactions Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny An alkyl is a Univalent radical consisting of Carbon and Hydrogen atoms arranged in a chain In the context of organic molecules aryl refers to any Functional group or Substituent derived from a Simple aromatic ring, may it be Phenyl [1] A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether" (ethoxyethane, CH3-CH2-O-CH2-CH3). A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. Anesthesia, or anaesthesia (see spelling differences; from Greek grc αν- an-, "without" and grc αἲσθησις Diethyl ether, also known as ether and ethoxyethane, is a clear colorless and highly Flammable liquid with a low Boiling point and a

Contents

Physical properties

Ether molecules cannot form hydrogen bonds among each other, resulting in a relatively low boiling point comparable to that of the analogous alcohols. In Chemistry, a molecule is defined as a sufficiently stable electrically neutral group of at least two Atoms in a definite arrangement held together by A hydrogen bond results from a Dipole-dipole force between an Electronegative atom and a Hydrogen atom bonded to Nitrogen, Oxygen The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon However, the differences in the boiling points of the ethers and their isometric alcohols become smaller as the carbon chains become longer, as the hydrophobic nature of the carbon chain becomes more predominant over the presence of hydrogen bonding. In Chemistry, hydrophobicity (from the combining form of water in Attic Greek hydro- and for fear phobos) refers to the physical property of

Ethers are slightly polar as the R - C - O - C - Z bond angle in the functional group is about 110 degrees, and the C - O dipole does cancel out. Ethers are more polar than alkenes but not as polar as alcohols, esters or amides of comparable structure. In Chemistry, an amide is one of three kinds of Compounds (sometimes called acid amide the organic Functional group characterized However, the presence of two lone pairs of electrons on the oxygen atoms makes hydrogen bonding with water molecules possible, causing the solubility of alcohols (for instance, butan-1-ol) and ethers (ethoxyethane) to be quite dissimilar.

Cyclic ethers such as tetrahydrofuran and 1,4-dioxane are totally miscible in water because of the more exposed oxygen atom for hydrogen bonding as compared to aliphatic ethers. "THF" redirects here For other uses see THF (disambiguation. In Organic chemistry, compounds composed of Carbon and Hydrogen are divided into two classes Aromatic compounds which contain Benzene rings

Ethers can act as Lewis bases. For instance, diethyl ether forms a complex with boron compounds, such as boron trifluoride diethyl etherate (BF3. Boron (ˈbɔərɒn is a Chemical element with Atomic number 5 and the chemical symbol B. Boron trifluoride is the Chemical compound with the formula BF3 OEt2). Ethers also coordinate to magnesium in Grignard reagents (RMgBr). The Grignard reaction, named for the French chemist François Auguste Victor Grignard, is an organometallic Chemical reaction in which Alkyl -

Nomenclature

In the IUPAC nomenclature system, ethers are named using the general formula "alkoxyalkane", for example CH3-CH2-O-CH3 is methoxyethane. IUPAC Nomenclature is a system of naming Chemical compounds and of describing the science of Chemistry in general Methoxyethane, also known as methyl ethyl ether, is a colorless gaseous Ether with a medicine-like odor If the ether is part of a more complex molecule, it is described as an alkoxy substituent, so -OCH3 would be considered a "methoxy-" group. In Chemistry (particularly Organic chemistry) methoxy refers to the Functional group consisting of a Methyl group bound to Oxygen The simpler alkyl radical is written in front, so CH3-O-CH2CH3 would be given as methoxy(CH3O)ethane(CH2CH3). An alkyl is a Univalent radical consisting of Carbon and Hydrogen atoms arranged in a chain The nomenclature of describing the two alkyl groups and appending "ether", e. g. "ethyl methyl ether" in the example above, is a trivial usage. In Chemistry and Zoology, a trivial name (also a Common name or vernacular name) is a non- Systematic name.

Similar structures

Not all compounds of the formula R-O-R are ethers.
Not all compounds of the formula R-O-R are ethers.

Ethers are not to be confused with the following classes of compounds with the same general structure R-O-R.

Primary, secondary, and tertiary ethers

The terms "primary ether", "secondary ether", and "tertiary ether" are occasionally used and refer to the carbon atom next to the ether oxygen. Nitrogen (ˈnaɪtɹəʤɪn is a Chemical element that has the symbol N and Atomic number 7 and Atomic weight 14 Sulfur or sulphur (ˈsʌlfɚ see spelling below) is the Chemical element that has the Atomic number 16 Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least An acetal is a Molecule with two single bonded oxygens attached to the same carbon atom A hemiaminal is a Functional group or type of Chemical compound that has a Hydroxyl group and an Amine attached to the same Carbon In Chemistry, an anhydride is a compound that can be considered as derived from another compound by subtracting the molecules of water. In a primary ether this carbon is connected to only one other carbon as in diethyl ether CH3-CH2-O-CH2-CH3. Diethyl ether, also known as ether and ethoxyethane, is a clear colorless and highly Flammable liquid with a low Boiling point and a An example of a secondary ether is diisopropyl ether (CH3)2CH-O-CH(CH3)2 and that of a tertiary ether is di-tert-butyl ether (CH3)3C-O-C(CH3)3. Diisopropyl ether is secondary Ether that is used as a Solvent. Di- tert -butyl ether is a colorless and liquid tertiary Ether that is used as a Solvent.

Dimethyl ether

A primary ether (diethyl ether)

A secondary ether (diisopropyl ether)

A tertiary ether (di-tert-butyl ether)


Dimethyl ether, a primary, a secondary, and a tertiary ether.

Polyethers

Polyethers are compounds with more than one ether group. While the term generally refers to polymers like polyethylene glycol and polypropylene glycol, low molecular compounds such as the crown ethers may sometimes be included. A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds Poly( Ethylene glycol) (PEG also known as poly( Ethylene oxide) (PEO or polyoxyethylene (POE is the most commercially important type of polyether Polypropylene glycol or polypropylene oxide is the Polymer of Propylene glycol. Crown ethers are heterocyclic Chemical compounds that consist of a ring containing several Ether groups

Organic reactions

Synthesis

Ethers can be prepared in the laboratory in several different ways.

R-OH + R-OH → R-O-R + H2O
This direct reaction requires drastic conditions (heating to 140 degrees Celsius and an acid catalyst, usually concentrated sulfuric acid). In Chemistry, a dehydration reaction is usually defined as a chemical reaction that involves the loss of water from the reacting molecule In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as Effective for making symmetrical ethers, but not as useful for synthesising asymmetrical ethers because the reaction will yield a mixture of ethers, making it usually not applicable:
3R-OH + 3R'-OH → R-O-R + R'-O-R + R'-O-R' + 3H2O
Conditions must also be controlled to avoid overheating to 170 degrees which will cause intramolecular dehydration,a reaction that yields alkenes. Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as In addition, the alcohol must be in excess.
R-CH2-CH2(OH) → R-CH=CH2 + H2O
Such conditions can destroy the delicate structures of some functional groups. In Organic chemistry, functional groups are specific groups of Atoms within Molecules that are responsible for the characteristic Chemical reactions There exist several milder methods to produce ethers.
R-O- + R-X → R-O-R + X-
This reaction is called the Williamson ether synthesis. In organic and Inorganic chemistry, nucleophilic substitution is a fundamental class of Substitution reaction in which an "electron rich" The haloalkanes (also known as halogenoalkanes or alkyl halides) are a group of Chemical compounds consisting of Alkanes such as Methane An alkoxide is the Conjugate base of an Alcohol and therefore consists of an organic group bonded to a negatively charged Oxygen atom An alkoxide is the Conjugate base of an Alcohol and therefore consists of an organic group bonded to a negatively charged Oxygen atom The haloalkanes (also known as halogenoalkanes or alkyl halides) are a group of Chemical compounds consisting of Alkanes such as Methane A halide is a Binary compound, of which one part is a Halogen Atom and the other part is an element or radical that is less The Williamson ether synthesis was developed by Alexander Williamson in 1850. It involves treatment of a parent alcohol with a strong base to form the alkoxide anion followed by addition of an appropriate aliphatic compound bearing a suitable leaving group (R-X). In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge A leaving group is an Atom or group of atoms that detaches from a chemical substance Suitable leaving groups (X) include iodide, bromide, or sulfonates. An iodide Ion is an iodine atom with a &minus1 charge. Compounds with iodine in formal Oxidation state &minus1 are called iodides A bromide Ion is a Bromine atom with charge of −1 Compounds with bromine in formal Oxidation state −1 are called bromides A sulfonate ion is an ion that contains the -S(=O2-O&minus Functional group. This method does not work if R is aromatic like in bromobenzene (Br-C6H5), however, if the leaving group is separated by at least one carbon from the benzene, the reaction should proceed (as in Br-CH2-C6H5). Bromobenzenes are a group of halobenzenes formed in a Substitution reaction between Bromine and Benzene with a Hydrogen bromide Likewise, this method only gives the best yields for primary carbons, as secondary and tertiary carbons will undergo E2 elimination on exposure to the basic alkoxide anion used in the reaction due to steric hindrance from the large alkyl groups. Aryl ethers can be prepared in the Ullmann condensation. The Ullmann condensation or Ullmann ether synthesis is a variation of the Ullmann reaction, in which a Phenol is coupled to an Aryl Halide
The R-X cannot be used to react with the alcohol. Phenol, is a toxic colourless Crystalline Solid with a sweet tarry odor commonly referred to as a "hospital smell" However, phenols can be used to replace the alcohol, while maintaining the alkyl halide. In Organic chemistry, phenols, sometimes called phenolics, are a class of Chemical compounds consisting of a Hydroxyl group (- Since phenols are acidic, they readily react with a strong base like sodium hydroxide to form phenoxide ions. In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and Sodium hydroxide ( Na[[hydroxide OH]]) also known as Lye, caustic soda and (incorrectly according to IUPAC nomenclature The phenoxide ion will then substitute the -X group in the alkyl halide, forming an ether with an aryl group attached to it in a reaction with an SN2 mechanism. The SN2 reaction (also known as bimolecular nucleophilic substitution) is a type of Nucleophilic substitution, where a lone pair from a Nucleophile
HO-C6H5 + OH- → O--C6H5
O--C6H5 + R-X → R-O-C6H5
R2C=CR2 + R-OH → R2CH-C(-O-R)-R2
Acid catalysis is required for this reaction. In Organic chemistry, an alkene, olefin, or olefine is an unsaturated Chemical compound containing at least one Carbon In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are Catalysis is the process in which the rate of a Chemical reaction is increased by means of a Chemical substance known as a catalyst Often, Mercury trifluoroacetate (Hg(OCOCF3)2 is used as a catalyst for the reaction, creating an ether with Markovnikov regiochemistry. Vladimir Vasilyevich Markovnikov (Марковников Владимир Васильевич also spelled as Markownikoff ( December 22, 1838 in Tetrahydropyranyl ethers are used as protective groups for alcohols. Tetrahydropyran, or oxane, is the Organic compound consisting of a saturated six-membered ring containing five carbon atoms and one oxygen atom A protecting group or protective group is introduced into a molecule by chemical modification of a Functional group in order to obtain Chemoselectivity

Cyclic ethers which are also known as epoxides can be prepared:

Reactions

Structure of the polymeric diethyl ether peroxide
Structure of the polymeric diethyl ether peroxide

Ethers in general are of very low chemical reactivity. Organic reactions are:

Ethers are hydrolyzed only under drastic conditions like heating with boron tribromide or boiling in hydrobromic acid. Hydrolysis is a Chemical reaction during which one or more water molecules are split into hydrogen and hydroxide ions which may go on to participate in further reactions Boron tribromide, BBr3 is a liquid compound containing Boron and Bromine. Hydrobromic Acid is formed by dissolving the diatomic molecule Hydrogen bromide in water Lower mineral acids containing a halogen, such as hydrochloric acid will cleave ethers, but very slowly. Hydrochloric acid is the Solution of Hydrogen chloride ( H[[Chlorine Cl]] in water Hydrobromic acid and hydroiodic acid are the only two that do so at an appreciable rate. Hydrogen iodide (HI is a Diatomic molecule. Aqueous solutions of HI are known as hydroiodic acid or hydriodic acid, a Strong acid. Certain aryl ethers can be cleaved by aluminium chloride. Aluminium chloride (AlCl3 is a compound of Aluminium and Chlorine.
Epoxides, or cyclic ethers in three-membered rings, are highly susceptible to nucleophilic attack and are reactive in this fashion. An epoxide is a cyclic Ether with only three ring atoms This ring approximately is an Equilateral triangle, i
Primary and secondary ethers with a CH group next to the ether oxygen easily form highly explosive organic peroxides (e. An explosive material is a material that either is chemically or otherwise Energetically unstable or produces a sudden expansion of the material usually accompanied Organic peroxides are Organic compounds containing the Peroxide Functional group (ROOR' g. diethyl ether peroxide) in the presence of oxygen, light, and metal and aldehyde impurities. Diethyl ether peroxides are a class of Organic peroxides that slowly form in Diethyl ether upon storage under air light or in the presence of metal by Autoxidation An aldehyde is an organic compound containing a terminal Carbonyl group. For this reason ethers like diethyl ether and THF are usually avoided as solvents in industrial processes

Important ethers

Chemical structure of ethylene oxide Ethylene oxide The smallest cyclic ether. "THF" redirects here For other uses see THF (disambiguation. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution.
Chemical structure of dimethyl ether Dimethyl ether An aerosol spray propellant. Dimethyl ether is the organic compound with the formula CH3OCH3 Aerosol spray is a type of dispensing system which creates an aerosol mist of liquid particles
Chemical structure of diethyl ether Diethyl ether A common low boiling solvent (b. Diethyl ether, also known as ether and ethoxyethane, is a clear colorless and highly Flammable liquid with a low Boiling point and a p. 34. 6°C).
Chemical structure of dimethoxyethane Dimethoxyethane (DME) A high boiling solvent (b. Dimethoxyethane, also known as glyme, monoglyme, dimethyl glycol, ethylene glycol dimethyl ether, dimethyl cellosolve, and p. 85°C):
Chemical structure of dioxane Dioxane A cyclic ether and high boiling solvent (b. p. 101. 1°C).
Chemical structure of THF Tetrahydrofuran (THF) A cyclic ether, one of the most polar simple ethers that is used as a solvent. "THF" redirects here For other uses see THF (disambiguation.
Chemical structure of anisole Anisole (methoxybenzene) An aryl ether and a major constituent of the essential oil of anise seed. Anisole, also known as methoxybenzene, is a Colorless Liquid with a smell similar to that of Anise seed and can be quite nauseating An essential oil is a concentrated Hydrophobic Liquid containing volatile Aroma compounds from Plants They are also known as volatile '''Anise''' or Aniseed, less commonly anís (stressed on the second syllable ( Pimpinella anisum) is a Flowering plant in the family Apiaceae
Chemical structure of 18-crown-6 Crown ethers Cyclic polyethers that are used as phase transfer catalysts. Crown ethers are heterocyclic Chemical compounds that consist of a ring containing several Ether groups A phase transfer catalyst or PTC in Chemistry is a Catalyst which facilitates the migration of a reactant in a Heterogeneous system from one
Chemical structure of polyethylene glycol Polyethylene glycol (PEG) A linear polyether, e. Poly( Ethylene glycol) (PEG also known as poly( Ethylene oxide) (PEO or polyoxyethylene (POE is the most commercially important type of polyether g. used in cosmetics:

See also

References

  1. ^ International Union of Pure and Applied Chemistry. In the late 19th century " luminiferous aether " (or " ether " meaning light-bearing aether, was the term used to describe a medium for the propagation The International Union of Pure and Applied Chemistry ( IUPAC) (aɪjuːpæk or ay-yoo-pec) is an international Non-governmental organization "ethers". Compendium of Chemical Terminology Internet edition. Compendium of Chemical Terminology (ISBN 0-86542-684-8 is a book published by IUPAC containing internationally accepted definitions for terms in Chemistry.

External links

Project Gutenberg, abbreviated as PG, is a volunteer effort to Digitize, archive and distribute Cultural works

Dictionary

ether

-noun

  1. (organic chemistry, countable) A compound containing an oxygen atom bonded to two hydrocarbon groups.
  2. (organic chemistry, uncountable) Diethyl ether (C4H10O), a compound used as an early anaesthetic.
  3. (ancient philosophy and alchemy, uncountable) A classical physical element, considered as prevalent in the heavens and inaccessible to humans. In some versions of alchemy, this was the fifth element in addition to air, earth, fire and water.
  4. (archaic, physics, uncountable) A substance (aether) once thought to fill all space that allowed Electromagnetic waves to pass through it and interact with matter, without exerting any resistance to matter or energy (disproved by Einstein in his Theory of Relativity).
  5. (poetic or literary) The sky or heavens; the upper air.

Ether

-proper noun

  1. The ancient American prophet of Mormon theology who wrote the Book of Ether in the Book of Mormon.
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