Butanediol, also called butylene glycol, may refer to any one of four stable structural isomers:
1,2-Butanediol 1,3-Butanediol 1,4-Butanediol 2,3-Butanediol
Geminal diols There are also two geminal diols (gem-diols), which are less stable:
1,1-Butanediol, hydrate of butanal 2,2-Butanediol, hydrate of butanone
Isobutylene glycol and methylpropanediol Isobutylene glycol may be considered a kind of butylene glycol, similarly to butane historically including n-butane and i-butane (isobutane). The modern name for the closely related type of compounds is methylpropanediol. There are two stable structural isomers:
2-methylpropane-1,2-diol 2-methylpropane-1,3-diol and one unstable geminal diol:
2-methylpropane-1,1-diol (not a glycol), hydrate of 2-methylpropanal (isobutyraldehyde) These three methylpropanediols are structural isomers of butanediols. They are not chiral.
Examples 2-Methylpropane-1,3-diol derivatives:
Crisnatol, an experimental medication 2-Methyl-2-propyl-1,3-propanediol, medication precursor and active metabolite
See also C4H10O2 Diol Alkanediol Hydroxyl-substituted butanes Butyl alcohol Butanetriol Butanetetrol (butanetetraol), including 4-carbon sugar alcohols Erythritol Threitol
References