In organic chemistry, the term ethynyl designates a functional group with a double bond 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), and referred to in IUPAC chemical nomenclature as -yne suffix. Also sometimes designed as ethinyl in compounds (ethinylestradiol, ethisterone (ethinyltestosterone)). See main page alkynes.
  • The ethynyl radical (HC≡C·), the compound found in interstellar medium, and transiently on earth during chemical reactions.
  • The ethynyl carbanion Acetylide (HC≡C)

See also