Rerbicides

Abstract

The present invention relates to herbicidally active pyridino-/pyrimidino-pyridine derivatives, as well as to processes and intermediates used for the preparation of such derivatives. The invention further extends to herbicidal compositions comprising such derivatives, as well as to the use of such compounds and compositions in controlling undesirable plant growth: in particular the use in controlling weeds, in crops of useful plants.

1 . A compound of Formula (I) 
       
         
           
           
               
               
           
         
         or a salt thereof, wherein: 
         R 2  is C 1 -C 6 alkyl, C 1 -C 6 haloalkyl, cyano, —C(O)OC 1 -C 6 alkyl, C 1 -C 6 alkoxy, or phenyl; 
         R 3  is selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, and (CR a R b ) g R 5 ; 
         R a  is hydrogen or C 1 -C 2  alkyl; 
         Rh is hydrogen or C 1 -C 2  alkyl; 
         R 4  is selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, C 2 -C 6 haloalkenyl, C 1 -C 6 alkoxyC 1 -C 3 alkyl-, C 1 -C 6 haloalkyl- and —(CR a R b ) q R 5 ; 
         R 5  is —C(O)OC 1 -C 6 alkyl, —C 3 -C 10 cycloalkyl, -aryl and -heteroaryl wherein said aryl and heteroaryl are optionally substituted by 1 to 3 independent R 8 ; 
         or R 3  and R 4  together with the nitrogen to which they are attached, form a saturated or partially unsaturated 4-6 membered ring system optionally containing 1 or 2 further heteroatoms independently selected from S, O and N, wherein said ring is optionally substituted by 1 to 3 R 8 ; 
         R 6  and R 7  are independently selected from the group consisting of hydrogen and C 1 -C 6 alkyl; 
         each R 8  is independently selected from the group consisting of halogen, C 1 -C 6  alkyl and C 1 -C 6 alkoxy-, C 1 -C 6  haloalkyl, C 1 -C 6  haloalkoxy-, cyano and S(O) p (C 1 -C 6 alkyl); 
         n is 0 or 1; 
         p is 0, 1, or 2;
 and 
 
         q is 0, 1, or 2; 
         with the proviso that: 
         (a) R 3  and R 4  are not both H, when R 2  is methyl, and n is 0. 
       
     
     
         2 . The compound of Formula (I) according to  claim 1 , wherein R 2  is C 1 -C 6 alkyl or C 1 -C 6 haloalkyl. 
     
     
         3 . The compound of Formula (I) according to  claim 1 , wherein R 3  is selected from the group consisting of hydrogen, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, phenyl, benzyl, —(CH 2 )C 3 -C 10 cycloalkyl, —CH(CH 3 )phenyl, —CH 2 C(O)OC 1 -C 6 alkyl and —CH(CH 3 )C(O)OC 1 -C 6 alkyl wherein said benzyl and phenyl are optionally substituted by 1-3 independent R 8 . 
     
     
         4 . The compound of Formula (I) according to  claim 3 , wherein R 3  is selected from the group consisting of hydrogen, methyl, -allyl, -but-2-ynyl, —CH 2 CO 2 CH 3 , —CH(CH 3 )C(O)OCH 3 , —(CH 2 )-cPr, phenyl, benzyl and —CH(CH 3 )phenyl wherein the benzyl and phenyl are optionally substituted by one or two substituents selected from the group consisting of —CF 3 , F, Cl and methoxy. 
     
     
         5 . The compound of Formula (I) according to  claim 4 , wherein R 3  is hydrogen or methyl. 
     
     
         6 . The compound of Formula (I) according to  claim 1 , wherein R 4  is hydrogen. 
     
     
         7 . The compound of Formula (I) according to  claim 1 , selected from the group consisting of A14, A15, A34, A35 and A44 as shown in the table below: 
       
         
           
                 
                 
                 
                 
               
                     
                     
                 
                     
                     
                   Cmpd 
                     
                 
                     
                     
                   ID 
                   Structure 
                 
                     
                     
                 
                     
                     
                   A14 
                   
                     
                       
                       
                           
                           
                       
                     
                   
                 
                     
                     
                 
                     
                     
                   A15 
                   
                     
                       
                       
                           
                           
                       
                     
                   
                 
                     
                     
                 
                     
                     
                   A34 
                   
                     
                       
                       
                           
                           
                       
                     
                   
                 
                     
                     
                 
                     
                     
                   A35 
                   
                     
                       
                       
                           
                           
                       
                     
                   
                 
                     
                     
                 
                     
                     
                   A44 
                   
                     
                       
                       
                           
                           
                       
                     
                   
                 
                     
                     
                 
             
                
                
                
                
               
               
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
     
     
         8 . A herbicidal composition comprising a compound of Formula (I) as defined in  claim 1  and an agriculturally acceptable formulation adjuvant. 
     
     
         9 . The herbicidal composition according to  claim 8 , further comprising at least one additional pesticide. 
     
     
         10 . A method of controlling weeds at a locus comprising application to the locus of a weed controlling amount of a compound of formula (I) as defined in  claim 1 .