the invention discloses a new method for producing enantiomer - enriched 1 - amino - 4 -- cyclopent - 2 - ene derivatives of the general formulae and in which r 1 is hydrogen or a possibly substituted c 1 - 8 alkyl radical , aryl radical or cycloalkyl radical and r 2 is acyl . according to said method a racemic 1 - amino - 4 -- cyclopent - 2 - ene derivative of general formula , in which r 1 has the meaning given above , is converted using a hydrolase and in the presence of an acylation agent