In organic chemistry, alkynols ( hydroxyalkynes) are organic compounds that contain both alkyne and alcohol functional groups. Thus, as structural features, they have a C≡C triple bond and a hydroxyl group. Some alkynols play a role as intermediates in the chemical industry.
The shortened term ynol typically refers to alkynols with the hydroxyl group affixed to one of the two carbon atoms composing the triple bond (), the triple-bond analogues to enols.
The deprotonated of ynols are known as ynolates, the triple-bond analogues to enolates.
Synthesis
Alkynols may be formed by the
alkynylation of carbonyl compounds, usually in liquid ammonia.
Ynolates
Ynolates are chemical compounds with a negatively charged oxygen atom attached to an
alkyne functionality.
They were first synthesized in 1975 by Schöllkopf and Hoppe via the
N-Butyllithium fragmentation of 3,4-diphenylisoxazole.
Synthetically, they behave as ketene precursors or .
Ynol–ketene tautomerism
Ynols can interconvert with
, much like
can with
and
. The ynol
tautomer is usually unstable, does not survive long, and changes into the ketene. This is because
oxygen is more electronegative than
carbon and thus forms
Bond energy Covalent bond. For instance,
ethynol quickly interconverts with
ethenone:
Literature
-
Allinger, Cava, de Jongh, Johnson, Lebel, Stevens: Organische Chemie, 1. Auflage, Walter de Gruyter, Berlin 1980, , p. 749.
-
Hans Beyer / Wolfgang Walter: Lehrbuch der Organischen Chemie, 19. Auflage, S. Hirzel Verlag, Stuttgart 1981, , pp. 98–99, 122.
-
K. Peter C. Vollhardt, Neil E. Schore: Organische Chemie, 4. Auflage, Wiley-VCH, Weinheim 2005, , p. 632.
See also
