INDUSTRIAL PROCESS FOR THE PREPARATION OF L-CARNITINE

摘要

The present invention describes a process for the industrial production of L - carnitine, comprising the enantioselective reduction of an alkyl 4-chloro-3- oxobutyrate or 4-chloro-3-oxobutyramide. The optically active 3-hydroxy derivative thus obtained is reacted with trimethylamine, obtaining crude L- carnitine, which is then finally purified. The catalyst used for the reducti on is a complex of ruthenium bound to a penta-atomic bis-heteroaromatic system. The reduction reaction, performed in controlled conditions of hydrogen pressure, substrate concentration, temperature, and substrate: catalyst mola r ratio, enables 4-chloro-3-hydroxybutyrate or 4-chloro-hydroxybutyramide to b e obtained in a high yield. The process described, which leads to L-carnitine being obtained, is easily applicable on an industrial scale.