New dextrorotatory enantiomers of phenoxy propionic acid derivatives of the formula ##STR1## in which R.sup.1 represents a radical of the formula ##STR2## wherein X.sup.1 represents hydrogen or halogen,X.sup.2 represents halogen or trifluoromethyl,X.sup.3 represents halogen or trifluoromethyl,X.sup.4 represents hydrogen or halogen andX.sup.5 represents hydrogen or halogen,Y represents oxygen or the radical SO.sub.m,whereinm represents 0, 1 or 2,R.sup.2 represents hydrogen or methyl,n represents 1 or 2 andR.sup.3 and R.sup.4 independently of one another represent hydrogen, halogen, alkyl with 1 to 4 carbon atoms, alkoxy with 1 to 4 carbon atoms, alkylthio with 1 to 4 carbon atoms, nitro, cyano or alkoxycarbonyl with 1 to 4 carbon atoms in the alkoxy group, and their use as herbicides.