gamma-Butyrolactone Chemical compound Descriptionγ-Butyrolactone is a hygroscopic colorless, water-miscible liquid with a weak characteristic odor. It is the simplest 4-carbon lactone. It is mainly used as an intermediate in the production of other chemicals, e.g. methyl-2-pyrrolidone. Wikipedia Formula: C4H6O2 Boiling point: 204 °C Density: 1.13 g/cm³ Solubility in water: Miscible Solubility: soluble in CCl4, methanol, ethanol, acetone, benzene, ethyl ether Acidity (pKa): 4.5