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Many ethyl-containing compounds are generated by electrophilic ethylation, i.e. treatment of nucleophiles with sources of Et+. Triethyloxonium tetrafluoroborate t3OF4 is such a reagent. For good nucleophiles, less electrophilic reagents are employed, such as ethyl halides.
"Ueber die Constitution des Aethers und seiner Verbindungen"
(On the composition of ethers and their compounds), ''Annalen der Pharmacie'', 9 : 1–39.) In reporting on Liebig's findings (and related work by others), Berzelius coined the names "methyl" and "ethyl" for the "radicals" CH3 and C2H5, respectively. From Jacob Berzelius, ''Årsberättelsen om framsteg i fysik och kemi'' nnual report on progress in physics and chemistry(Stockholm, Sweden: P.A. Norstedt & Söner, 1835)
p. 376
''"Man får då ge namn åt etherradikalerna; man kan kalla den äldre C4H10, ''ethyl'', den nyare C2H6, ''methyl'', … "'' (One may then give names to ether radicals; one can call the older neC4H10, ''ethyl'', the newer neC2H6, ''methyl'', … ote: At that time, chemists used the wrong atomic masses (e.g., 6 for carbon instead of 12); hence the coefficients shown here must be divided by two. In his translation into German of Berzelius' report, the German chemist
381.
organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J ...
, an ethyl group (abbr. Et) is an alkyl
In organic chemistry, an alkyl group is an alkane missing one hydrogen.
The term ''alkyl'' is intentionally unspecific to include many possible substitutions.
An acyclic alkyl has the general formula of . A cycloalkyl is derived from a cycloa ...
substituent
A substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms ''substituent'' and ''functional group'', as well as '' side ...
with the formula
In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...
, derived from ethane (). ''Ethyl'' is used in the International Union of Pure and Applied Chemistry
The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...
's nomenclature of organic chemistry for a saturated two-carbon moiety
Moiety may refer to:
Chemistry
* Moiety (chemistry), a part or functional group of a molecule
** Moiety conservation, conservation of a subgroup in a chemical species
Anthropology
* Moiety (kinship), either of two groups into which a society is ...
in a molecule, while the prefix "''eth-''" is used to indicate the presence of two carbon atoms in the molecule.
Ethylation
Ethylation is the formation of a compound by introduction of the ethyl group. The most widely practiced example of this reaction is the ethylation of benzene withethylene
Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds).
Ethylene ...
to yield ethylbenzene
Ethylbenzene is an organic compound with the formula . It is a highly flammable, colorless liquid with an odor similar to that of gasoline. This monocyclic aromatic hydrocarbon is important in the petrochemical industry as an reaction interme ...
, a precursor to styrene, which is a precursor to polystyrene
Polystyrene (PS) is a synthetic polymer made from monomers of the Aromatic hydrocarbon, aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin pe ...
. Approximately 24.7 million tons of ethylbenzene were produced in 1999.
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Many ethyl-containing compounds are generated by electrophilic ethylation, i.e. treatment of nucleophiles with sources of Et+. Triethyloxonium tetrafluoroborate t3OF4 is such a reagent. For good nucleophiles, less electrophilic reagents are employed, such as ethyl halides.
Stereochemistry
In unsymmetrical ethylated compounds, the methylene protons in the ethyl substituent are diastereotopic. Chiral reagents are known to stereoselectively modify such substituents.Etymology
The name of the group is derived from the Aether, the first-born Greek elemental god of air (and at that time a general term for any highly volatile compound) and " hyle", referring to "stuff". The name "ethyl" was coined in 1835 by the Swedish chemist Jöns Jacob Berzelius.In 1834, the German chemist Justus Liebig had argued that the group C2H5 constituted a "radical" (a cluster of atoms that did not undergo changes during chemical reactions). (See: Justus Liebig (1834"Ueber die Constitution des Aethers und seiner Verbindungen"
(On the composition of ethers and their compounds), ''Annalen der Pharmacie'', 9 : 1–39.) In reporting on Liebig's findings (and related work by others), Berzelius coined the names "methyl" and "ethyl" for the "radicals" CH3 and C2H5, respectively. From Jacob Berzelius, ''Årsberättelsen om framsteg i fysik och kemi'' nnual report on progress in physics and chemistry(Stockholm, Sweden: P.A. Norstedt & Söner, 1835)
p. 376
''"Man får då ge namn åt etherradikalerna; man kan kalla den äldre C4H10, ''ethyl'', den nyare C2H6, ''methyl'', … "'' (One may then give names to ether radicals; one can call the older neC4H10, ''ethyl'', the newer neC2H6, ''methyl'', … ote: At that time, chemists used the wrong atomic masses (e.g., 6 for carbon instead of 12); hence the coefficients shown here must be divided by two. In his translation into German of Berzelius' report, the German chemist
Friedrich Wöhler
Friedrich Wöhler () FRS(For) Hon FRSE (31 July 180023 September 1882) was a German chemist known for his work in inorganic chemistry, being the first to isolate the chemical elements beryllium and yttrium in pure metallic form. He was the fi ...
transliterated "ethyl" as "Aethyl". (See: Jöns Jacob Berzelius with Friedrich Wöhler, trans., ''Jahresbericht über die Fortschritte der physischen Wissenschaften'' (Annual report on the progress of the physical sciences), 15 :381.
See also
*Functional group
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the r ...
References