2-Pyrrolidone, also known as 2-pyrrolidinone or butyrolactam, is an organic compound consisting of a 5-membered lactam, making it the simplest γ-lactam.

2-Pyrrolidone is produced industrially almost exclusively by treating aqueous gamma-butyrolactone with ammonia at a temperature of 250–290 °C and pressures ranging from 0.4–1.4 MPa over solid magnesium silicate catalysts.

[3] Alternative routes include the catalytic or electrochemical reduction of succinimide, the carbonylation of allylamine,[4] the hydrogenation of succinonitrile under hydrolytic conditions, and the reaction of maleic or succinic anhydride in aqueous ammonia with Pd–Ru-catalysts.

[3] In 2010, the worldwide demand for 2-pyrrolidone was estimated to be 32.000 t. Important manufacturers of 2-pyrrolidone are BASF and ISP (International Speciality Products, now Ashland Inc.).

[5] A variety of pharmaceutical drugs are 2-pyrrolidone derivatives, including cotinine, doxapram, povidone, and ethosuximide, and the racetams.