Tetrolic acid

2-Butynoic acid
Names
	Preferred IUPAC name But-2-ynoic acid
	Other names Tetrolic acid; But-2-ynoic acid
Identifiers
CAS Number	590-93-2;
3D model (JSmol)	Interactive image;
ChemSpider	61810 ;
ECHA InfoCard	100.008.815
CompTox Dashboard (EPA)	DTXSID4060444 ;
	SMILES CC#CC(=O)O;
Properties
Chemical formula	C4H4O2
Molar mass	84.074 g·mol−1
Melting point	77 to 78 °C (171 to 172 °F; 350 to 351 K)
Boiling point	203 °C (397 °F; 476 K)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

2-Butynoic acid is a short-chain carboxylic acid, described by the formula CH₃CH≡CHCO₂H. It is more commonly known as tetrolic acid.

Production

2-Butynoic acid is manufactured on multi kilo scale by treatment of propyne with a strong base, followed by carbon dioxide^[1].

The compound is a white crystalline solid.