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. It is a colorless liquid that is miscible with water and most common organic solvents.
2-Pyrrolidone itself and it various derivatives, especially N-methylpyrrolidone, have a variety of industrial uses.
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.
The reaction is carried out in a tubular reactor which is packed with the solid catalyst. The latter is arranged as a fixed bed and the reaction is carried out in the vapor phase. Product yields of 75–85% are reached. After subsequent distillation and purification, the desired 2-pyrrolidone is obtained with a purity of 99.5%.
Alternative routes include the catalytic or electrochemical reduction of succinimide, the carbonylation of allylamine,[1] the hydrogenation of succinonitrile under hydrolytic conditions, and the reaction of maleic or succinic anhydride in aqueous ammonia with Pd–Ru-catalysts.
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.).
2-Pyrrolidone itself is used in inkjet cartridges.[2]
A variety of pharmaceutical drugs are 2-pyrrolidone derivatives, including cotinine, doxapram, povidone, and ethosuximide, and the racetams.
The chemical is an intermediate in the production of the polyvinylpyrrolidone precursor vinylpyrrolidone.
2-Pyrrolidone is relatively innocuous with an LD50 in the range of grams per kilogram (rats, oral). It is not mutagenic. It can be an eye irritant.[2]