Propiolaldehyde

{{Chembox | ImageFile = Propinal.svg | ImageSize = 200 | PIN = Prop-2-ynal | OtherNames = Propynal; Propiolic aldehyde | Section1 = {{Chembox Identifiers | CASNo = 624-67-9 | CASNo_Ref = {{cascite|correct|CAS}} | Beilstein = 1098318 | ChEBI = 27976 | ChEMBL = 722 | ChemSpiderID = 11721 | EC_number = 210-857-4 | KEGG = C05985 | PubChem = 12222 | UNII = SJ8A65XF7N | UNII_Ref = {{fdacite|correct|FDA}} | StdInChI=1S/C3H2O/c1-2-3-4/h1,3H | StdInChIKey = IJNJLGFTSIAHEA-UHFFFAOYSA-N | SMILES = C#CC=O }} | Section2 = {{Chembox Properties | C=3|H=2|O=1 | Appearance = colorless liquid | Density = 0.9152 g/cm³ | MeltingPtC = | BoilingPtC = 54-57 | Solubility = }} | Section3 = {{Chembox Hazards | GHS_ref=[https://pubchem.ncbi.nlm.nih.gov/compound/12222#section=Safety-and-Hazards] | GHSPictograms = {{GHS02}}{{GHS05}}{{GHS06}}{{GHS07}} | GHSSignalWord = Danger | HPhrases = {{H-phrases|225|226|300|315|317|318|319|330|335}} | PPhrases = {{P-phrases|210|233|240|241|242|243|260|261|264|264+265|270|271|272|280|284|301+316|302+352|303+361+353|304+340|305+351+338|305+354+338|316|317|319|320|321|330|332+317|333+317|337+317|362+364|370+378|403+233|403+235|405|501}} | MainHazards = | FlashPt = | AutoignitionPt = }} }}

'''Propiolaldehyde''' is an organic compound with molecular formula HC₂CHO. It is the simplest chemical compound containing both alkyne and aldehyde functional groups. It is a colorless liquid with explosive properties.<ref name=eros>{{cite encyclopedia |surname1=P. Perlmutter |chapter=Propargyl Aldehyde |date=2001 |doi=10.1002/047084289X.rp262m |title=Encyclopedia of Reagents for Organic Synthesis |isbn=978-0471936237}}</ref>

==Reactions== The compound exhibits reactions expected for an electrophilic alkynyl aldehyde. It is a dienophile and a good Michael acceptor. Grignard reagents add to the carbonyl center.<ref name=eros/> Its explosive properties are attributed to the exothermicity of its polymerization.<ref name=eros/>

==Preparation== Its acetal can be prepared from acrolein.<ref>{{cite journal |doi=10.15227/orgsyn.059.0010|title=Alkyness via Phase Transfer-Catalyzed Dehydrohalogenation: Propiolaldehyde Diethyl Acetal|journal=Organic Syntheses|year=1979|volume=59|page=10|author=A. Le Coq and A. Gorgues}}</ref>

==Occurrence in interstellar medium== Propynal has been observed in the interstellar medium. It is hypothesized to be formed from a carbon monoxide-acetylene complex.<ref>{{citation |last=Zhou |first=Li |author2=Ralf I. Kaiser |title=Pathways to Oxygen-Bearing Molecules in the Interstellar Medium and in Planetary Atmospheres: Cyclopropenone (c-C3H2O) and Propynal (HCCCHO) |journal=The Astrophysical Journal |year=2008 |volume=686 |issue=2 |pages=1493–1502 |doi=10.1086/591072 |doi-access=free }}</ref> Another possible pathway is through the reaction of propynylidyne (C₃H) with water.<ref>{{citation |last=Xie |first=Hong-bin |author2=Chang-bin Shao |title=Radical-Molecule Reaction C3H + H2O on Amorphous Water Ice: A Promising Route for Interstellar Propynal |journal=The Astrophysical Journal |year=2007 |volume=670 |issue=1 |pages=449–456 |doi=10.1086/520757 |doi-access=free }}</ref>

==Hazards== The compound is explosive, possibly because it tends to polymerize.<ref name=eros/>

==See also== * Acrolein * Propiolic acid

==References== {{reflist}}

{{Molecules detected in outer space}}

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Category:Aldehyde dehydrogenase inhibitors Category:Aldehydes Category:Alkyne derivatives Category:Human drug metabolites