organic chemistry Organic chemistry is a subdiscipline within chemistry involving the science, 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.Clay ...

, the term ethynyl designates a

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 res ...

with a

double bond In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist betw ...

with 2 carbon atoms both with sp hybridisation and a triple bond(1 sigma and 2 pi bond) . It is a species similar to acetylene (or in IUPAC ethyne ) with a less H atom thus joined to root chain. * An ethynyl group (HC≡C–), also designated as acetylenic group (from

acetylene Acetylene ( systematic name: ethyne) is the chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pur ...

), and referred to in IUPAC chemical nomenclature as -yne suffix. Also sometimes designed as ''ethinyl'' in compounds (

ethinylestradiol Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. In the past, EE was widely used for various indications such as the treatment of menopausal symptoms, gynecological dis ...

, ethisterone (ethinyltestosterone)). See main page

alkyne \ce \ce Acetylene \ce \ce \ce Propyne \ce \ce \ce \ce 1-Butyne In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and no ...

s. * The

ethynyl radical The ethynyl radical (systematically named λ3-ethyne and hydridodicarbon(''C''—''C'')) is an organic compound with the chemical formula C≡CH (also written CHor ). It is a simple molecule that does not occur naturally on Earth but is abunda ...

(HC≡C·), the compound found in interstellar medium, and transiently on earth during chemical reactions. * The ethynyl carbanion Acetylide (HC≡C⁻)

See also