The present invention relates to N-[[2-fluoro-4-[2-hydroxy-3-(3,4,5-trichlorophenyl)-3-(trifluoromethyl)-1-pyrrolidinyl]phenyl]methyl]cyclopropanecarboxamides in enantiomerically pure or in an enantiomerically enriched form, to processes for preparation thereof and to the use thereof for controlling animal pests.本發明係關於呈鏡像異構物純或呈鏡像異構物富集形式之N-[[2-氟-4-[2-羥基-3-(3,4,5-三氯苯基)-3-(三氟甲基)-1-吡咯啶基]苯基]甲基]環丙烷甲醯胺、製備其之方法及其用於控制動物有害生物之用途。