Article · Wikipedia archive · Last revised Jun 10, 2026

Butynone

Butynone is an organic compound and the simplest ynone. It is a reagent used in organic synthesis as a dienophile and Michael acceptor.

Last revised
Jun 10, 2026
Read time
≈ 2 min
Length
359 w
Citations
4
Source
Butynone
source ↗
Names
IUPAC name
But-3-yn-2-one
Other names
  • Butyn-2-one
  • Acetylacetylene
  • Methyl ethynyl ketone
  • Acetylethyne
Identifiers
3D model (JSmol)
605353
ChEBI
ChemSpider
ECHA InfoCard 100.014.395
EC Number
  • 215-834-2
49292
UNII
  • InChI=1S/C4H4O/c1-3-4(2)5/h1H,2H3
    Key: XRGPFNGLRSIPSA-UHFFFAOYSA-N
  • CC(=O)C#C
Properties
HC2COCH3
Molar mass 116.072 g·mol−1
Boiling point 85 °C (185 °F; 358 K)
Hazards
GHS labelling:
GHS02: FlammableGHS06: ToxicGHS07: Exclamation mark
Danger
H225, H300, H315, H319, H335
P210, P233, P240, P241, P242, P243, P261, P264, P270, P271, P280, P301+P310+P330, P303+P361+P353, P304+P340+P312, P305+P351+P338, P332+P313, P337+P313, P362, P370+P378, P403+P233, P403+P235, P405, P501
Safety data sheet (SDS) Sigma-Aldrich Co., product no. 161314.
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Butynone is an organic compound and the simplest ynone. It is a reagent used in organic synthesis as a dienophile and Michael acceptor.

Preparation

The triisopropylsilyl derivative of butynone is prepared by oxidation of the corresponding derivative of 2-butynol, itself prepared from TIPS acetylene by deprotonation followed by nucleophilic addition to acetaldehyde.1

Applications

Butynone was one of the reagents used in the discovery of the Bohlmann–Rahtz pyridine synthesis.2

Butynone and its derivatives participate in cycloaddition reactions, yielding a variety of heterocycles. The electron-deficient alkyne group participates in the azide-alkyne Huisgen cycloaddition to produce 1,2,3-triazine methyl ketones.3 [4+2+1] cycloaddition with 1,2-phenylenediamine and furfural derivatives gives benzodiazepine rings.4

Sources

Sources

  1. James A. Marshall, Patrick Eidam, and Hilary Schenck Eidam (2008). "Synthesis of 4-triisopropylsilyl-3-butyn-2-ol by asymmetric transfer hydrogenation". Organic Syntheses. 84: 120{{cite journal}}: CS1 maint: multiple names: authors list (link).
  2. Bagley, Mark; Glover, Christian; Merritt, Eleanor (2007). "The Bohlmann-Rahtz Pyridine Synthesis: From Discovery to Applications". Synlett (16): 2459–2482. doi:10.1055/s-2007-986674.
  3. Bakka, Thomas A.; Strøm, Morten B.; Andersen, Jeanette H.; Gautun, Odd R. (2017). "Methyl propiolate and 3-butynone: Starting points for synthesis of amphiphilic 1,2,3-triazole peptidomimetics for antimicrobial evaluation". Bioorganic & Medicinal Chemistry. 25 (20): 5380–5395. doi:10.1016/j.bmc.2017.07.060. hdl:10037/11419. PMID 28797773.
  4. Jiang, Jingjing; Queneau, Yves; Popowycz, Florence (2023). "Ammonium Acetate Catalyzed Formation of 1,5-Benzodiazepines through [4+2+1] Cycloaddition Involving 5-Hydroxymethylfurfural". European Journal of Organic Chemistry. 26 (19) e202300144. doi:10.1002/ejoc.202300144.