The invention relates to α-oxygenated or α-thiolated carboxylic acid phenethylamide derivatives of the general formula Iincluding the optical isomers thereof and mixtures of such isomers, wherein A stands for optionally substituted aryl or optionally substituted heteroaryl X is oxygen or sulfur Y is oxygen or sulfur R1 is hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, haloalkyl, haloalkenyl, haloalkynyl or halocycloalkyl R2 is hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkyl-alkyl, alkoxy-alkyl, alkoxy-alkenyl, alkoxy-alkynyl, whereof all alkyl- alkenyl-, alkynyl-, or cycloalkyl-groups me be optionally substituted by halogen or optionally substituted aryl-alkyl, optionally substituted aryl-alkenyl, optionally substituted aryl-alkynyl or optionally substituted aryloxy-alkyl R3 is hydrogen, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkyl-alkyl, alkoxy-alkyl, alkoxy-alkenyl, alkoxy-alkynyl, whereof all alkyl- alkenyl-, alkynyl-, or cycloalkyl-groups me be optionally substituted by halogen or is optionally substituted aryl-alkyl, optionally substituted aryl-alkenyl, optionally substituted aryl-alkynyl, optionally substituted aryloxy-alkyl, optionally substituted heteroaryl-alkyl, optionally substituted heteroaryl-alkenyl or optionally substituted heteroaryl-alkynyl R4 is alkyl, alkenyl, alkynyl, alkoxy-alkyl, alkoxy, alkenyloxy, alkynyloxy, alkylthio, alkanoyl, alkylamino, dialkylamino, alkoxycarbonyl, whereof all alkyl- alkenyl or alkynyl-groups me be optionally substituted by halogen or is halogen, cyano, nitro, amino, formyl or carboxyl R5 is hydrogen, alkyl, alkenyl or alkynyl n is an integer 0,1, 2, 3, or 4 B1 represents a bridge member -(CR10R11)q- or -(CHR10R11)r-Z-(CR12R13)s , wherein q is an integer 2, 3 or 4 r is an integer 0, 1, 2, 3 s is an integer 1, 2 or 3, provided that (r + s) is either 1, 2 or 3 Z is -O-, -S-, -SO- -SO2-, NR6-, -CO-, -OOC-, -COO-, -NR6-CO- or -CO-NR6- R6 is hydrogen or alkyl R10, R11, R12 and R13 independently of each other a
