Chemical structure of 1,4-butanediol

1,4-Butanediol (C₄H₁₀O₂, molecular weight 90.122 Da) is an alcohol derivate of the alkane butane, carrying two hydroxyl groups. Its industrial synthesis starts with acetylene, which is reacted with two molecules of formaldehyde to form 1,2-Butynediol in a Reppe synthesis. This product is subsequently hydrogenated to give 1,4-butanediol.

In organic chemistry, 1,4-butanediole is used for the synthesis of γ-butyrolactone. In presence of phosphoric acid and high temperature, it dehydrates to the important solvent tetrahydrofuran.

It is also used as an illicit drug known by recreational users as "One Comma Four". It exerts the same effects GHB, which is a metabolic product of 1,4-butanediol.