Amine–boranes: effective reducing agents for the deracemisation of dl-amino acids using l-amino acid oxidase from Proteus myxofaciens

Abstract The deracemisation of dl -α-amino acids using l -amino acid oxidase from Proteus myxofaciens and amine-boranes as chemical reducing agents has been investigated. Amine-boranes were found to be of particular interest in terms of reactivity and chemoselectivity compared to sodium borohydride and cyanoborohydride. Starting from the racemate, a range of d -amino acids were obtained in yields of up to 90% and e.e. >99%.