Substituted N-aryl nitrogen-containing heterocyclic compounds

Abstract

The invention relates to novel substituted N-aryl nitrogen-containing heterocyclic compounds of the general formula (I) and to the compounds isomeric to the substituted N-aryl nitrogen-containing heterocyclic compounds of the formula (I), of the formulae (Ia) and (Ib) in which Q 1 , Q 2 , R 1 , R 2 and Ar have the meanings given in the description, processes for their preparation and their use as herbicides.

1 . A substituted N-aryl nitrogen-containing heterocyclic compound of the general formula (I)  
       
         
           
           
               
               
           
         
       
       in which 
 Q 1  represents oxygen or sulfur, Q 2  represents oxygen or sulfur,  
 R 1  represents hydrogen, cyano or formyl or represents alkyl which is optionally substituted by halogen, cyano, carboxyl, alkoxy, alkenyloxy, alkinyloxy, alkylthio, alkenylthio, alkinylthio, alkoxycarbonyl, alkenyl-oxycarbonyl or alkinyloxycarbonyl,  
 R 1  furthermore represents alkenyl or alkinyl, in each case optionally substituted by halogen,  
 R 1  furthermore represents alkylcarbonyl, alkenylcarbonyl, alkinylcarbonyl, alkoxycarbonyl, alkenyloxycarbonyl or alkinyloxycarbonyl, in each case optionally substituted by halogen,  
 R 1  furthermore represents cycloalkyl or cycloalkylcarbonyl, in each case optionally substituted by halogen, cyano or carboxyl,  
 R 2  represents hydrogen, cyano or formyl, or represents alkyl which is optionally substituted by halogen, cyano, carboxyl, alkoxy, alkenyloxy, alkinyloxy, alkylthio, alkenylthio, alkinylthio, alkoxycarbonyl, alkenyloxycarbonyl or alkinyloxycarbonyl,  
 R 2  furthermore represents alkenyl or alkinyl, in each case optionally substituted by halogen,  
 R 2  furthermore represents alkylcarbonyl, alkenylcarbonyl, alkinylcarbonyl, alkoxycarbonyl, alkenyloxycarbonyl or alkinyloxycarbonyl, in each case optionally substituted by halogen,  
 R 2  furthermore represents cycloalkyl or cycloalkylcarbonyl, in each case optionally substituted by halogen, cyano or carboxyl, and  
 Ar represents the substituted monocyclic or bicyclic aryl or heteroaryl grouping defined below.  
                     
  in which 
 R 3  represents hydrogen or halogen,  
 R 4  represents hydrogen or halogen,  
 R 5  represents cyano, carboxyl, chlorocarbonyl, carbamoyl, thiocarbamoyl, hydroxyl or halogen, or represents alkyl, alkoxy or alkoxycarbonyl, in each case optionally substituted by halogen,  
 R 6  represents the following grouping 
 —A 1 —A 2 —A 3   
  in which 
 A 1  represents a single bond, or represents oxygen, sulfur, —SO—, —SO 2 —, —CO— or the grouping —N—A 4 —, in which A 4  represents hydrogen, hydroxyl, alkyl, alkenyl, alkinyl, alkoxy, aryl, alkylcarbonyl, arylcarbonyl, alkylsulfonyl or arylsulfonyl,  
 A 1  furthermore represents alkanediyl, alkenediyl, azaalkenediyl, alkanediyl, cycloalkanediyl, cycloalkenediyl or phenylene, in each case optionally substituted by halogen,  
 A 2  represents a single bond, or represents oxygen, sulfur, —SO—, —SO 2 —, —CO— or the grouping —N—A 4 —, in which A 4  represents hydrogen, hydroxyl, alkyl, alkoxy, aryl, alkylsulfonyl or arylsulfonyl,  
 A 2  furthermore represents alkanediyl, alkenediyl, azaalkenediyl, alkinediyl, cycloalkanediyl, cycloalkenediyl or phenylene, in each case optionally substituted by halogen,  
 A 3  represents hydrogen, with the proviso that in this case A 1  and/or A 2  do(es) not represent any single bond,  
 A 3  furthermore represents hydroxyl, mercapto, amino, cyano, isocyano, thiocyanato, nitro, carboxyl, carbamoyl, thiocarbamoyl, sulfo, chlorosulfonyl or halogen, or represents alkyl, alkoxy, alkylthio, alkylsulfinyl, alkylsulfonyl, alkylamino, dialkylamino, alkoxycarbonyl or dialkoxy(thio)-phosphoryl, in each case optionally substituted by halogen or alkoxy,  
 A 3  furthermore represents alkenyl, alkenyloxy, alkenylthio, alkenylamino, alkylidenamino, alkenyloxycarbonyl, alkinyl, alkinyloxy, alkinylthio, alkynylamino or alkinyloxycarbonyl, in each case optionally substituted by halogen  
 A 3  furthermore represents cycloalkyl, cycloalkyloxy, cycloalkylalkyl, cycloalkylalkoxy, cycloalkylidenamino, cycloalkyloxycarbonyl or cycloalkylalkoxycarbonyl, in each case optionally substituted by halogen, cyano, carboxyl. alkyl and/or alkoxy carbonyl,  
 A 3  furthermore represents aryl, aryloxy, aralkyl, arylalkoxy, aryloxycarbonyl or arylalkoxycarbonyl, in each case optionally substituted by nitro, cyano, carboxyl, halogen, alkyl, halogenalkyl, allyloxy, halogenalkyloxy and/or alkoxy-carbonyl,  
 A 3  furthermore represents in each case optionally completely or partly hydrogenated pyrrolyl, pyrazolyl, imidazolyl, triazolyl, furyl, oxiranyl, oxetanyl, dioxolanyl, thienyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, pyridinyl, pyrimidinyl, triazinyl, pyrazolylalkyl, furylalkyl, thienylalkyl, oxazolylalkyl, isoxazolylalkyl, thiazolylalkyl, pyridinylalkyl, pyrimidinylalkyl, pyrazolylalkoxy or furylalkoxy, or represents perhydropyranylalkoxy or pyridylalkoxy, and  
 
 
 R 7  represents hydrogen or halogen,  
 or in each case two adjacent radicals—R 3  and R 4 , R 4  and R 5 , R 5  and R 6  or R 6  and R 7 —together represent one of the following groupings 
 —Q 3 —CQ 4 —, —Q 3 —CQ 4 —Q 5 —, —Q 3 —C(R 8 ,R 9 )—Q 5 —, —C(R 8 ,R 9 )—CQ 4 —, —C(R 8 ,R 9 )—Q 3 —CQ 4 —, —Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—, —Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—Q 5 —, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —, —Q 3 —C(R 8 )═C(R 8 )—, —C(R 8 )═C(R 8 )—CQ 4 —, —Q 3 —C(R 8 ,R 9 )—CQ 4 —, —N(R 10 )—C(R 8 ,R 9 )—CQ 4 —, —C(R 8 )═N—, —Q—CQ 4 —C(R 8 ,R 9 )—, —Q 3 —CQ 4 —N(R 10 )—, —Q 3 —C(R 8 ,R 9 )—CQ 4 —N—(R 10 )—, —C(R 8 ,R 9 )—Q 3 —CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—N(R 10 )—, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —C(R 8 )═C(R 8 )—N(R 10 )—, —C(R 8 )═C(R 8 )—CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—CQ 4 —N(R 10 )—N(R 10 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —C(R 8 )═N—N(R 10 )—, —Q 3 —CQ 4 —C(R 8 ,R 9 )—N(R 10 )—, Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )— 
 
  in which 
 Q 3 , Q 4 , and Q 5  are identical or different and in each case represent oxygen or sulfur,  
 R 8  and R 9  are identical or different and individually represent hydrogen, halogen or alkyl or together represent alkanediyl, and  
 R 10  represents hydrogen or hydroxyl, or represents alkyl, alkylcarbonyl, alkoxycarbonyl or alkylsulfonyl which are optionally substituted by cyano, halogen, alkoxy, alkyl-carbonyl or alkoxy-carbonyl, or represents alkenyl or alkinyl, in each case optionally substituted by halogen, or represents cycloalkyl or cycloalkylalkyl, in each case optionally substituted by halogen or alkyl, or represents alkoxy or alkenyloxy, in each case optionally substituted by halogen, or represents arylalkyl or arylalkoxy, in each case optionally substituted by cyano, halogen, allyl, halogenoalkyl, alkoxy or halogenoalkoxy,  
 excluding the compounds 4-(3,4-dichlorophenyl)-1,2-dimethyl-5-thioxo-1,2,4-triazolidin-3-one and 4-(4-chloro-3-trifluoromethylphenyl)-1,2-dimethyl-5-thioxo-1,2,4-triazolidin-3-one.  
 
 
     
     
         2 . A substitute N-aryl nitrogen-containing heterocyclic compound of the general formula (Ia)  
       
         
           
           
               
               
           
         
       
       in which 
 Q 1 , Q 2 , R 1 , R 2  and Ar have the meanings given in  claim 1 .  
 
     
     
         3 . A substituted N-aryl nitrogen-containing heterocyclic compound of the general formula (Ib)  
       
         
           
           
               
               
           
         
       
       in which 
 Q 1 , Q 2 , R 1 , R 2  and Ar have the meanings given in  claim 1 .  
 
     
     
         4 . A process for the preparation of a substituted N-aryl nitrogen-containing heterocyclic compound of the general formula (I) or of a compound of the formula (Ia) or (Ib) as claimed in  claims 1  to  3 , which comprises a procedure in which 
 (a) a (thio)semicarbazide derivative of the general formula (II)  
                     
  in which 
 Q 1 , Q 2 , R 1 , R 2  and Ar have the meanings given in  claim 1  and  
 R represents alkyl,  
 
 is subjected to a cyclizing condensation reaction, if appropriate in the presence of a reaction auxiliary and if appropriate in the presence of a diluent, and thereafter, if appropriate, electrophilic or nucleophilic substitution reactions are carried out in the customary manner in the context of the definition of the substituents,  
 or in wich  
 (b) an aryliminoheterocyclic compound of the general formula (III)  
                     
  in which 
 Q 1 , Q 2 , R 1 , R 2  and Ar have the abovementioned meanings, — or a compound of the formula (Ia) or (Ib)—above— 
 
 is isomerized thermally (“pyrolytically”), if appropriate in the presence of a reaction auxiliary and if appropriate in the presence of a diluent.  
 
     
     
         5 . A substituted N-aryl nitrogen-containing heterocyclic compound of the general formula (I), (Ia) or (Ib) as claimed in  claims 1  to  3 , in which 
 Q 1  represents oxygen or sulfur,  
 Q 2  represents oxygen or sulfur,  
 R 1  represents hydrogen, cyano or formyl, or represents C 1 -C 6 -alkyl, in each case optionally substituted by fluorine, chlorine, cyano, carboxyl, C 1 -C 4 -alkoxy, C 3 -C 4 -alkenyloxy, C 3 -C 4 -alkyloxy, C 1 -C 4 -alkylthio, C 3 -C 4 -alkenylthio, C 3 -C 4 -alkylthio, C 1 -C 4 -alkoxy carbonyl, C 3 -C 4 -alkenyloxy-carbonyl or C 3 -C 4 -alkinyloxy carbonyl,  
 R 1  furthermore represents C 3 -C 6 -alkenyl or C 3 -C 6 -alkinyl, in each case optionally substituted by fluorine or chlorine,  
 R 1  furthermore represents C 1 -C 6 -alkyl-carbonyl, C 3 -C 6 -alkenyl-carbonyl, C 3 -C 6 -alkinylcarbonyl, C 1 -C 6 -alkoxy-carbonyl, C 3 -C 6 -alkenyloxy-carbonyl or C 3 -C 6 -alkinyloxy-carbonyl, in each case optionally substituted by fluorine or chlorine,  
 R 1  furthermore represents C 3 -C 6 -cycloalkyl or C 3 -C 6 -cycloalkyl-carbonyl, in each case optionally substituted by fluorine, chlorine, bromine, cyano or carboxyl,  
 R 2  represents hydrogen, cyano or formyl, or represents C 1 -C 6 -alkyl, in each case optionally substituted by fluorine, chlorine, cyano, carboxyl, C 1 -C 4 -alkoxy, C 3 -C 4 -alkenyloxy, C 3 -C 4 -alkinyloxy, C 1 -C 4 -alkylthio, C 3 -C 4 -alkenylthio, C 3 -C 4 -adylthio, C 1 -C 4 -alkoxy-carbonyl, C 3 -C 4 -alkenyloxy-carbonyl or C 3 -C 4 -alkinyloxy-carbonyl,  
 R 2  furthermore represents C 3 -C 6 -alkenyl or C 3 -C 6 -alkinyl, in each case optionally substituted by fluorine or chlorine,  
 R 2  furthermore represents C 1 -C 6 -alkyl-carbonyl, C 3 -C 6 -alkenyl-carbonyl, C 3 -C 6 -alkinyl-carbonyl, C 1 -C 6 -alkoxy-carbonyl, C 3 -C 6 -alkenyloxy-carbonyl or C 3 -C 6 -alkinyloxy carbonyl, in each case optionally substituted by fluorine or chlorine,  
 R 2  furthermore represents C 3 -C 6 -cycloalkyl or C 3 -C 6 -cycloalkyl-carbonyl, in each case optionally substituted by fluorine, chlorine, bromine, cyano or carboxyl, and  
 Ar represents the, substituted monocyclic or bicyclic aryl or heteroaryl grouping defined below  
                     
  in which 
 R 3  represents hydrogen, fluorine, chlorine or bromine,  
 R 4  represents hydrogen, fluorine, chlorine or bromine,  
 R 5  represents cyano, carboxyl, chlorocarbonyl, carbamoyl, thiocarbamoyl, hydroxyl, fluorine, chlorine, bromine or represents alkyl, alkoxy or alkoxycarbonyl having in each case up to 4 carbon atoms and in each case optionally substituted by fluorine and/or chlorine,  
 R 6  represents the following grouping 
 —A 1 —A 2 —A 3   
  in which 
 A 1  represents a single bond, or represents oxygen, sulfur, —SO—, —SO 2 —, —CO— or the grouping —NA 4 —, in which A 4  represents hydrogen, hydroxyl, C 1 -C 4 -alkyl, C 3 -C 4 -alkenyl, C 3 -C 4 -alkinyl, C 1 -C 4 -alkoxy, phenyl, C 1 -C 4 -alkyl carbonyl, phenyl-carbonyl, C 1 -C 4 -alkyl-sulfonyl or phenylsulfonyl,  
 A 1  furthermore represents C 1 -C 6 -alkanediyl, C 2 -C 6 -alkenediyl, C 2 -C 6 -azaalkenediyl, C 2 -C 6 -alkenediyl, C 3 -C 6 -cycloalkanediyl, C 3 -C 6 -cycloalkenediyl or phenylene, in each case optionally substituted by fluorine, chlorine or bromine,  
 A 2  represents a single bond, or represents oxygen, sulfur, —SO—, —SO 2 —, —CO— or the grouping —N—A 4 —, in which A 4  represents hydrogen, hydroxyl, C 1 -C 4 -alkyl, C 1 -C 4 -alkoxy, phenyl, C 1 -C 4 -alkylsulfonyl or phenylsulfonyl,  
 A 2  furthermore represents C 1 -C 6 -alkenediyl, C 2 -C 6 -alkenediyl, C 2 -C 6 -azaakenediyl, C 2 -C 6 -alkinediyl, C 3 -C 6 -cloallediyl, C 3 -C 6 -cycloalkenediyl or phenylene, in each case optionally substituted by fluorine, chlorine or bromine,  
 A 3  represents hydrogen, with the proviso that in this case A 1  and/or A 2  do(es) not represent a single bond,  
 A 3  furthermore represents hydroxyl, mercapto, amino, cyano, isocyano, thiocyanato, nitro, carboxyl, carbamoyl, thiocarbamoyl, sulfo, chlorosulfonyl, fluorine, chlorine or bromine,  
 A 3  furthermore represents alkyl, alkoxy, alkylthio, alkylsulfinyl, alkylsulfonyl, alkylamino, dialkylamino, alkoxycarbonyl or dialkoxy(thio)phosphoryl having in each case 1 to 6 carbon atoms in the alkyl groups and in each case optionally substituted by fluorine, chlorine or C 1 -C 4 -alkoxy,  
 A 3  furthermore represents alkenyl, alkenyloxy, alkenylamino, alkylidenamino, alkenyloxycarbonyl, alkinyl, alkinyloxy, alkinylamino or alkinyloxycarbonyl having in each case 2 to 6 carbon atoms in the alkenyl, alkylidene or alkinyl groups and in each case optionally substituted by fluorine or chlorine,  
 A 3  furthermore represents cycloalkyl, cycloalkyloxy, cycloalkylalkyl, cycloalkylalkoxy, cycloalkylidenamino, cycloalkyloxycarbonyl or cycloalkylalkoxycarbonyl having in each case 3 to 6 carbon atoms in the cycloalkyl groups and where appropriate 1 to 4 carbon atoms in the alkyl groups and in each case optionally substituted by fluorine, chlorine, cyano, carboxyl, C 1 -C 4 -alkyl and/or C 1 -C 4 -alkoxy-carbonyl,  
 A 3  furthermore represents phenyl, phenyloxy, phenyl-C 1 -C 4 -alkyl, phenyl-C 1 -C 4 -alkoxy, pentyloxycarbonyl or phenyl-C 1 -C 4 -alkoxycarbonyl, in each case optionally substituted by nitro, cyano, carboxyl, fluorine, chlorine, bromine, C 1 -C 4 -alkyl, C 1 -C 4 -halogenalkyl, C 1 -C 4 -alkyloxy, C 1 -C 4 -halogenalkyloxy and/or C 1 -C 4 -alkoxycarbonyl,  
 A 3  furthermore represents in each case optionally completely or partly hydrogenated pyrrolyl, pyrazolyl, imidazolyl, triazolyl, furyl, oxiranyl, oxetanyl, dioxolanyl, thienyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, pyridinyl, pyrimidinyl, triazinyl, pyrazolyl-C 1 -C 4 -alkyl, furyl-C 1 -C 4 -alkyl, thienyl-C 1 -C 4 -alkyl, oxalolyl-C 1 -C 4 -alkyl, isoxazolyl-C 1 -C 4 -alkyl, thiazolyl-C 1 -C 4 -alkyl, pyridinyl-C 1 -C 4 -alkyl, pyridinyl-C 1 -C 4 -alkyl, pyrazolylmethoxy or furthermore, or represents perhydropyranylmethoxy or pyridylmethoxy, and  
 
 
 R 7  represents hydrogen, fluorine or chlorine  
 or in each case two adjacent radicals—R 3  and R 4 , R 4  and R 5 , R 5  and R 6  or R 6  and R 7 —together represent one of the following groupings 
 —Q 3 —CQ 4 —, —Q 3 —CQ 4 —Q 5 —, —Q 3 —C(R 8 ,R 9 )—Q 5 —, —C(R 8 ,R 9 )—CQ 4 —, —C(R 8 ,R 9 )—Q 3 —CQ 4 —, —Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—, Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—Q 5 —, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —, —Q 3 —C(R 8 )═C(R 8 )—, —C(R 8 )═C(R 8 )—CQ 4 —, —Q 3 —C(R 8 ,R 9 )—CQ 4 —, —N(R 10 )—C(R 8 ,R 9 )—CQ 4 —, —C(R 8 )═N—, —Q 3 —CQ 4 —C(R 8 ,R 9 )—, —Q 3 —CQ 4 —N(R 10 )—, —Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—N(R 10 )—, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—, CQ 4 —N(R 10 )—, —C(R 8 )═C(R 8 )—N(R 10 )—, —C(R 8 )═C(R 8 )—CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—, —CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—Q 3 —CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —N(R 10 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —C(R 8 )═N—N(R 10 )—, —Q 3 —CQ 4 —C(R 8 ,R 9 )—N(R 10 )—, Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—,  
 
  in which 
 Q 3 , Q 4  and Q 5  are identical or different and in each case represent oxygen or sulfur,  
 R 8  and R 9  are identical or different and individually represent oxygen, fluorine, chlorine, bromine or C 1 -C 4 -alkyl or together represent C 2 -C 5 -alkanediyl, and  
 R 10  represents hydrogen or hydroxyl, or represents alkyl, alkylcarbonyl, alkoxycarbonyl or alkylsulfonyl having in each case 1 to 6 carbon atoms in the alkyl groups and in each case optionally substituted by cyano, fluorine, chlorine, C 1 -C 4 -alkoxy, C 1 -C 4 -alkyl carbonyl or C 1 -C 4 -alkoxy-carbonyl,  
 R 10  furthermore represents alkenyl or alkinyl having in each case 2 to 6 carbon atoms and in each case optionally substituted by fluorine, chlorine or bromine,  
 R 10  furthermore represents cycloalkyl or cycloalkylalkyl having in each case 3 to 6 carbon atoms in the cycloalkyl groups and where appropriate 1 to 3 atoms in the alkyl group and in each case optionally substituted by fluorine, chlorine, bromine or C 1 -C 4 -alkyl,  
 R 10  furthermore represents alkoxy or alkenyloxy having in each case up to 6 carbon atoms and in each case optionally substituted by fluorene and/or chlorine, and  
 R 10  furthermore represents benzyl or benzyloxy, in each case optionally substituted by cyano, fluorene, chlorine, C 1 -C 4 -alkyl, C 1 -C 4 -halogenoalkyl, C 1 -C 4 -alkoxy or C 1 -C 4 -halogenoalkoxy,  
 
 excluding the compounds 4-(3,4-dichloro-phenyl)-1,2-dimethyl-5-thioxo-1,2,4-tiazolidin-3-one and 4-(4-chloro-3-trifluoromethyl-phenyl)-1,2-dimethyl-5-thioxo-1,2,4-triazolidin-3-one.  
 
     
     
         6 . A substituted N-aryl nitrogen-containing heterocyclic compound of the general formula (I), (Ia) or (Ib) as claimed in  claims 1  to  3 , in which 
 Q 1  represents oxygen or sulfur,  
 Q 2  represents oxygen or sulfur,  
 R 1  represents hydrogen, cyano or formyl, or represents methyl, ethyl, n- or i-propyl or n-, i-, s- or t-butyl, in each case optionally substituted by fluorine, chlorine, cyano, carboxyl, methoxy or ethoxy,  
 R 1  furthermore represents propenyl, butenyl, propinyl or butinyl, in each case optionally substituted by fluorine or chlorine,  
 R 1  furthermore represents acetyl, propionyl, methoxycarbonyl or ethoxy-carbonyl, in each case optionally substituted by fluorine or chlorine,  
 R 1  furthermore represents cyclopropyl which is optionally substituted by fluorine or chlorine,  
 R 2  represents hydrogen, cyano or formyl, or represents methyl, ethyl, n- or i-propyl or n-, i-, s- or t-butyl, in each case optionally substituted by fluorine, chlorine, cyano, carboxyl, methoxy or ethoxy,  
 R 2  furthermore represents propenyl, butenyl, propinyl or butinyl, in each case optionally substituted by fluorine or chlorine,  
 R 2  furthermore represents acetyl, propionyl, methoxycarbonyl or ethoxy-carbonyl, in each case optionally substituted by fluorine or chlorine,  
 R 2  furthermore represents cyclopropyl which is optionally substituted by fluorine or chlorine, and  
 Ar represents the substituted monocyclic or bicyclic aryl or heteroaryl grouping defined below  
                     
  in which 
 R 3  represents hydrogen, fluorine or chlorine,  
 R 4  represents hydrogen, fluorine or chlorine,  
 R 5  represents cyano, thiocarbamoyl, chlorine, bromine, methyl, trifluoromethyl, methoxy, difluoromethoxy or trifluoro-methoxy,  
 R 6  represents the following grouping 
 —A 1 —A 2 —A 3   
  in which 
 A 1  represents a single bond, or represents oxygen, sulfur, —SO—, —SO 2 —, —CO— 0  or the grouping —N—A 4 —, in which A 4  represents hydrogen, hydroxyl, methyl, ethyl, n- or i-propyl, methoxy, ethoxy, n- or i-propoxy, methylsulfonyl or ethylsulfonyl,  
 A 1  furthermore represents methylene, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, ethene-1,2,-diyl, propane-1,2-diyl, propane-1,3-diyl, ethine-1,2-diyl, propine-1,2-diyl or propine-1,3-diyl,  
 A 2  represents a single bond, or represents oxygen, sulfur, —SO—, —SO 2 —, —CO— or the grouping —N—A 4 —, in which A 4  represents oxygen, hydroxyl, methyl, ethyl, n- or i-propyl, methoxy, ethoxy, n- or i-propoxy, methylsulfonyl, ethylsulfonyl, n- or i-propylsulfonyl or phenylsulfonyl,  
 A 2  furthermore represents methylene, ethane-1,1-diyl, ethane-1,2-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3-diyl, ethene-1,2-diyl, propane-1,2-diyl, propane-1,3-diyl, ethine-1,2-diyl, propine-1,2-diyl or propine-1,3-diyl,  
 A 3  represents hydrogen, with the proviso that in this case A 1  and/or A 2  do(es) not represent a single bond,  
 A 3  furthermore represents hydroxyl, amino, cyano, nitro, carboxyl, carbamoyl, sulfo, fluorine, chlorine or bromine,  
 A 3  furthermore represents methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl, n-, i-, s- or t-pentyl, methoxy, ethoxy, n- or i-propoxy, n-, i-, s- or t-butoxy, n-, i-, s- or t-pentyloxy, methylthio, ethylthio, n- or i-propylthio, n-, i-, s- or t-butylthio, methylsulfinyl, ethylsulfinyl, n- or i-propylsulfinyl, methylsulfonyl, ethylsulfonyl, n- or i-propylsulfonyl, methylamino, ethylamino, n- or i-propylamino, n-, i-, s- or t-butylamino, dimethylamino, diethylamino, methoxycarbonyl, ethoxycarbonyl, n- or i-propoxycarbonyl, dimethoxyphosphoryl, diethoxyphosphoryl, dipropoxyphosphoryl or diisopropoxyphosphoryl, in each case optionally substituted by fluorine, chlorine, methoxy or ethoxy,  
 A 3  furthermore represents propenyl, butenyl, propenyloxy, butenyloxy, propenylamino, butenylamino, propylidenamino, butylidenamino, propenyloxycarbonyl, butenyloxycarbonyl, propinyl, butinyl, propinyloxy, butinyloxy, propinylamino, butinylamino, propinyloxycarbonyl or butinyloxycarbonyl, in each case optionally substituted by fluorine or chlorine,  
 A 3  furthermore represents cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, cyclopropylmethyl, cyclobutylmethyl, cyclopentylmethyl, cyclohexylmethyl, cyclopropylmethoxy, cyclobutylmethoxy, cyclopentylmethoxy, cyclohexylmethoxy, cyclopentylidenamino, cyclobexylidenamino, cyclopentyloxycarbonyl, cyclohexyloxycarbonyl, cyclopentylmethoxycarbonyl or cyclohexylmethoxycarbonyl, in each case optionally substituted by fluorine, chlorine, cyano, carboxyl, methyl, ethyl, n- or i-propyl, methoxycarbonyl or ethoxycarbonyl,  
 A 3  furthermore represents phenyl, phenyloxy, benzyl, phenylethyl, benzyloxy, phenyloxycarbonyl or benzyloxycarbonyl, in each case optionally substituted by nitro, cyano, carboxyl, fluorine, chlorine, bromine, methyl, ethyl, n- or i-propyl, trifluoromethyl, methoxy, ethoxy, n- or i-propoxy, difluoromethoxy, trifluoromethoxy, methoxy-carbonyl and/or ethoxycarbonyl,  
 A 3  furthermore represents in each case optionally completely or partly hydrogenated pyrrolyl, pyrazolyl, imidazolyl, triazolyl, furyl, thienyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, pyridinyl, pyrimidinyl, triazinyl, pyrazolylmethyl, furylmethyl, thienylmethyl, oxazolylmethyl, isoxazolylmethyl, thiazolylmethyl, pyridinylmethyl, pyrimidinylmethyl, pyrazolylmethoxy, furylmethoxy or pyridylmethoxy,  
 R 7  represents hydrogen, fluorine or chlorine,  
 
 
 or in each case two adjacent radicals—R 3  and R 4 , R 4  and R 5 , R 5  and R 6  or R 6  and R 7 —together represent one of the following groupings 
 —Q 3 —CQ 4 —, —Q 3 —CQ 4 —Q 5 —, —Q 3 —C(R 8 ,R 9 )—Q 5 —, —C(R 8 ,R 9 )—CQ 4 —, —C(R 8 ,R 9 )—Q 3 —CQ 4 —, —Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 ), —Q—C(R 8 ,R 9 )—C(R 8 ,R 9 )—Q 5 —, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —, —Q 3 —(R 8 )═C(R 8 )—, —C(R 8 )═C(R 8 )—CQ 4 —, —Q 3 —C(R 8 ,R 9 )—CQ 4 —, —N(R 10 )—C(R 8 ,R 9 )—CQ 4 —, —C(R 8 )═N—, —Q 3 —CQ 4 —C(R 8 ,R 9 )—, —Q 3 —CQ 4 —N(R 10 )—, —Q 3 —CR(R 8 ,R 9 )—CQ 4 —N—(R 10 )—, —C(R 8 ,R 9 )—Q 3 —CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—N(R 10 )—, —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —C(R 8 )═C(R 8 )—N(R 10 )—, —C(R 8 )═C(R 8 )—CQ 4 —N(R 10 )—, —C(R 8 )═C(R 8 )—N(R 10 )—, —C(R 8 )═C(R 8 )—CQ 4 —N(R 10 )—, —C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —N(R 10 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—, —C(R 8 )═N—N(R 10 )—, —Q 3 —CQ 4 —C(R 8 ,R 9 )—N(R 10 )—, Q 3 —C(R 8 ,R 9 )—C(R 8 ,R 9 )—CQ 4 —N(R 10 )—,  
 
  in which 
 Q 3 , Q 4  and Q 5  are identical or different and in each case represent oxygen or sulfur,  
 R 8  and R 9  are identical or different and individually represent hydrogen, fluorine, chlorine, methyl or ethyl or together represent ethane-1,2-diyl(dimethylene), and  
 R 10  represents hydrogen or hydroxyl, or represents methyl, ethyl, n- or i-propyl or n-, i-, s- or t-butyl which are optionally substituted by cyano, fluorine, chlorine, methoxy, ethoxy, acetyl, propionyl, methoxycarbonyl or ethoxycarbonyl,  
 R 10  furthermore represents propenyl, butenyl, propinyl or butinyl, in each case optionally substituted by fluorine, chlorine or bromine,  
 R 10  furthermore represents cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclopropylmethyl, cyclobutylmethyl, cyclopentylmethyl or cyclohexylmethyl, in each case optionally substituted by fluorine, chlorine, bromine, methyl or ethyl,  
 R 10  furthermore represents methoxy, ethoxy, n- or i-propoxy, n-, i- or s-butoxy, propenyloxy or butenyloxy, in each case optionally substituted by fluorine and/or chlorine, and  
 R 10  furthermore represents benzyl or benzyloxy, in each case optionally substituted by cyano, fluorine, chlorine, methyl, ethyl, trifluoromethyl, methoxy, ethoxy, difluoromethyl or trifluoromethoxy,  
 
 excluding the compounds 4-(3,4-dichloro-phenyl)-1,2-dimethyl-5-thioxo-1,2,-triazolidin-3-one and 4-(4-chloro-3-trifluoromethyl-phenyl)1,2-diethyl-5-thioxo-1,2,4-triazolidin-3-one.  
 
     
     
         7 . A herbicidal composition which has a content of at least one N-aryl nitrogen-containing heterocyclic compound of the general formula (I), (Ia) or (Ib) as claimed in  claims 1  to  6 .  
     
     
         8 . A method of combating undesirable plants which comprises allowing an N-aryl nitrogen-containing heterocyclic compound of the general formula (I), (Ia) or (Ib) as claimed in  claims 1  to  6  to act on undesirable plants and/or their environment.  
     
     
         9 . The use of an N-aryl nitrogen-containing heterocyclic compound of the general formula (I), (Ia) or (Ib) as claimed in  claims 1  to  6  for combating undesirable plants.  
     
     
         10 . A process for the preparation of a herbicidal composition, which comprises mixing an N-aryl nitrogen-containing heterocyclic compound of the general formula (I), (Ia) or (Ib) as claimed in  claims 1  to  6  with extenders and/or surface-active substances.