Novel-alkynyl-substituted 3-phenylpyrrolidine-2,4-diones and use thereof as herbicides

Abstract

The present invention relates to novel effective alkynyl-substituted 3-phenylpyrrolidine-2,4-diones according to the general formula (I) or agrochemically acceptable salts thereof, where X═C 1 -C 4 -alkyl, C 1 -C 4 -haloalkyl or C 3 -C 6 -cycloalkyl; Y═C 1 -C 4 -alkyl or C 3 -C 6 -cycloalkyl, n=1, 2 or 3; m=1 or 2; R 1 ═C 1 -C 6 -alkyl, or C 3 -C 6 -cycloalkyl, R 2 =hydrogen or methyl; R 3 ═C 1 -C 3 -alkoxy-C 1 -C 3 -alkyl, or a saturated five- or six-membered heterocycle with an oxygen or sulphur atom; G=hydrogen, a cleavable group L or a cation E. The invention also relates to the use of the compounds according to the invention for controlling weeds and weed grasses in crops of useful plants.

1 . An alkynyl-substituted phenyl acetic acid of formula (VII), 
       
         
           
           
               
               
           
         
         wherein 
         X is C 1 -C 4 -alkyl, C 1 -C 4 -haloalkyl or C 3 -C 6 -cycloalkyl; 
         Y is C 1 -C 4 -alkyl or C 3 -C 6 -cycloalkyl; and 
         R 1  is C 1 -C 6 -alkyl or C 3 -C 6 -cycloalkyl; 
         with the proviso that the compound 2,6-dimethyl-4-propargylphenyl acetic acid is excluded. 
       
     
     
         2 . The alkynyl-substituted phenyl acetic acid of formula (VII) according to  claim 1 , wherein
 X is methyl, ethyl or cyclopropyl;   Y is methyl or ethyl; and   R 1  is methyl, ethyl, isopropyl or cyclopropyl.   
     
     
         3 . The alkynyl-substituted phenyl acetic acid of formula (VII) according to  claim 2 , wherein
 X is methyl or ethyl.   
     
     
         4 . The alkynyl-substituted phenyl acetic acid of formula (VII) according to  claim 1 , wherein
 X is ethyl;   Y is ethyl; and   R 1  is methyl.   
     
     
         5 . The alkynyl-substituted phenyl acetic acid of formula (VII) according to  claim 1 , wherein
 X is methyl;   Y is methyl; and   R 1  is methyl.   
     
     
         6 . The alkynyl-substituted phenyl acetic acid of formula (VII) according to  claim 1 , wherein
 X is methyl;   Y is ethyl; and   R 1  is cyclopropyl.   
     
     
         7 . The alkynyl-substituted phenyl acetic acid of formula (VII) according to  claim 1 , wherein
 X is methyl;   Y is methyl; and   R 1  is cyclopropyl.