Substituted 3-aryl-pyrrolidine-2,4-diones

Substituted 3-aryl-4-hydroxy-2-ones of the formula (I) ##STR352## in which X represents hydrogen, C.sub.1-6 -alkyl, halogen or C.sub.1-6 -alkoxy,

• Y represents hydrogen, C.sub.1-6 -alkyl, halogen, C.sub.1-6 -alkoxy or C.sub.1-3 -halogenoalkyl,
• Z represents C.sub.1-6 -alkyl, halogen or C.sub.1-6 -alkoxy,
• n represents a number from 0-3,
• R represents hydrogen (Ia) or the groups of the formula
• --CO--R.sup.1 (Ib)
• or
• --CO--O--R.sup.2 (Ic)
• in which
• R.sup.1 represents optionally halogen-substituted C.sub.1-20 -alkyl, C.sub.2-20 -alkenyl, C.sub.1-8 -alkoxy-C.sub.2-8 -alkyl, C.sub.1-8 -alkylthio-C.sub.2-8 -alkyl, C.sub.1-8 -polyalkoxy-C.sub.2-8 -alkyl or cycloalkyl which has 3-8 ring atoms and which can be interrupted by 1-2 oxygen and/or sulphur atoms,
• or represents phenyl which is optionally substituted by halogen, nitro, C.sub.1-6 -alkyl, C.sub.1-6 -alkoxy, C.sub.1-6 -halogenoalkyl or C.sub.1-6 -halogenolakoxy,
• or represents phenyl-C.sub.1-6 -alkyl which is optionally substituted by halogen, C.sub.1-6 -alkyl, C.sub.1-6 -alkoxy, C.sub.1-6 -halogenoalkyl or C.sub.1-6 -halogenoalkoxy,
• or represents phenoxy-C.sub.1-6 -alkyl which is optionally substituted by halogen or C.sub.1-6 -alkyl,
• R.sup.2 represents optionally halogen-substituted C.sub.1-20 -alkyl, C.sub.2-20 -alkenyl, C.sub.1-16 -alkoxy-C.sub.2-6 -alkyl or C.sub.1-8 -polyalkoxy-C.sub.2-8 -alkyl,
• or represents phenyl which is optionally substituted by halogen, nitro, C.sub.1-6 -alkyl, C.sub.1-6 -alkoxy or C.sub.1-6 -halogenoalkyl,
• A represents optionally halogen-substituted straight-chain or branched C.sub.1-12 -alkyl, C.sub.3-8 -alkenyl, C.sub.3-8 -alkinyl, C.sub.1-10 -alkoxy-C.sub.2-8 -alkyl, C.sub.1-8 -polyalkoxy-C.sub.2-8 -alkyl, C.sub.1-10 -alkylthio-C.sub.2-8 -alkyl, cycloalkyl which has 3-8 ring atoms and which can be interrupted by 1-2 oxygen and/or sulphur atoms, or represents aryl-C.sub.1-6 -alkyl which is optionally substituted by halogen, C.sub.1-6 -alkyl, C.sub.1-6 -halogenoalkyl, C.sub.1-6 -alkoxy or nitro,
• B represents phenyl or benzyl which are optionally monosubstituted or disubstituted by identical or different substituents selected from the group consisting of nitro, halogen, or in each case optionally halogen-substituted C.sub.1-4 -alkyl or C.sub.1-4 -alkoxy,
• and the pure enantiomeric forms of compounds of the formula (I).