1,4-Butynediol

1,4-Butynediol

Names
IUPAC name But-2-yne-1,4-diol
Other names Butynediol 2-Butyne-1,4-diol 1,4-Dihydroxy-2-butyne
Identifiers
CAS Number	110-65-6 Y
ChEBI	CHEBI:16413 Y
ChemSpider	7775 Y
Jmol 3D model	Interactive image
KEGG	C02497 Y
InChI InChI=1S/C4H6O2/c5-3-1-2-4-6/h5-6H,3-4H2 Y Key: DLDJFQGPPSQZKI-UHFFFAOYSA-N Y InChI=1/C4H6O2/c5-3-1-2-4-6/h5-6H,3-4H2 Key: DLDJFQGPPSQZKI-UHFFFAOYAT
SMILES OCC#CCO
Properties
Chemical formula	C4H6O2
Molar mass	86.09 g/mol
Density	1.2 g/cm3
Melting point	52 to 55 °C (126 to 131 °F; 325 to 328 K)
Boiling point	238 °C (460 °F; 511 K) (decomposes >160 °C)
Vapor pressure	{{{value}}}
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

1,4-Butynediol is an organic compound that is an alkyne and a diol. It is a colourless, hygroscopic solid that is soluble in water and polar organic solvents. It is a commercially significant compound in its own right and as a precursor to other products.

Synthesis

1,4-Butynediol can be produced in the Reppe synthesis, where formaldehyde and acetylene are the reactants:

2 CH₂O + HC≡CH → HOCH₂CCCH₂OH

Several patented production methods use copper bismuth catalysts coated on an inert material. The normal temperature range for the reaction is 90 °C up to 150 °C, depending on the pressure used for the reaction which can range from 1 to 20 bar.

Applications

1,4-Butynediol is a precursor to 1,4-butanediol and 2-butene-1,4-diol by hydrogenation. It is also used in the manufacture of certain herbicides, textile additives, corrosion inhibitors, plasticizers, synthetic resins, and polyurethanes. It is the major raw material of vitamin B6. It is also used for brightening, preserving, and inhibiting nickel plating.

It reacts with a mixture of chlorine and hydrochloric acid to give mucochloric acid, HO₂CC(Cl)=C(Cl)CHO (see mucobromic acid).

Safety

1,4-Butynediol is corrosive and irritates the skin and eyes.