Patent Publication Number: US-4220466-A

Title: 4,5-Dicyanoimidazoles and use as herbicides

Description:
DESCRIPTION OF THE INVENTION 
     Background 
     In the United States there are now only five agricultural herbicides which account for about seventy percent of the entire herbicide market. Each of these herbicides belongs to a separate chemical class and each is used at the rate of more than ten million pounds per year. Other compounds of these same general chemical classes are also made and used, so that about eighty percent of the herbicides in use today belong to only five chemical classes. This situation has existed for more than a decade. A similar situation has also existed with respect to insecticides and has resulted in nearly disastrous development of insecticide-resistant strains of insects in some areas. The development of resistant strains of weeds occurs less readily than with insects because the existance of dormant seeds prevents the killing of almost all of the individuals of a single generation. The seeds which germinate during any given growing season inevitably are from several generations of plants. Nevertheless, continuous growing of the same crops and use of herbicides of the same chemical classes over the last two decades has had its effect. Strains of weeds are beginning to appear in some areas which are resistant to the best herbicides which are presently available. It is imperative that new chemical classes of herbicides be discovered and that various chemical types of herbicides be used in rotation, so as to prevent further development of resistant weeds. Otherwise it appears likely that within a few years each of the principal crops will be accompanied by weeds that have developed virtually the same selective herbicide resistance as the crop plants. 
     Summary 
     I have now discovered that a class of compounds having the general structural formula; ##STR3## in which R is H, lower (C 1  to C 5 ) alkyl or cycloalkyl, lower (C 1  to C 5 ) alkoxy, phenyl or substituted phenyl and R&#39; is one of the following; H, ##STR4## or phenylsulfonyl are useful as selective herbicides. Of this new class of herbicides, all except those in which R&#39; is hydrogen are believed to be novel compounds. 
     Detailed Description 
     Since the new herbicides belong to a large class, it is impractical to exemplify all of the variations of substituents within the class. In the discussion which follows, however, illustrative examples are given of representative types of compounds and synthesis methods are presented so that a skilled worker in the art will have the information necessary for preparation of the other compounds of the class which are not specifically exemplified. 
     Synthesis of the Herbicides 
     4,5-Dicyanoimidazole, and 2-methyl and 2-ethyl 4,5-dicyanoimidazoles may be prepared according to the method disclosed in U.S. Pat. No. 2,534,331 (1950). 
     2-Isopropyl-4,5-dicyanoimidazole and 2-tert.butyl-4,5-dicyanoimidazole are obtained by the condensation of isobutyraldehyde and pivalaldehyde, respectively with diaminomaleonitrile to give Schiff&#39;s bases. The oxidative cyclization of these intermediates with lead tetraacetate then gave the corresponding dicyanoimidazoles TABLE 1, equation (1). Similarly lead tetraacetate oxidation of ethoxymethyleneiminoaminomaleonitrile gave 2-ethoxy-4,5-dicyanoimidazole. These compounds have also been prepared by routes disclosed in the following references: 
     R. W. Begland et al, J. Org. Chem., 39 2341 (1974); 
     R. W. Begland, U.S. Pat. No. 3,806,517 (1974). 
     F. J. Wiegert, U.S. Pat. No. 3,778,446 (1973). ##STR5## 
     R=Branched alkyl group, aryl or substituted aryl group. 
     2-Alkyl- and 2-aryl-4,5-dicyanoimidazoles are allowed to react with the appropriate chlorothiolformate, chloroformate, acid chloride or sulfonyl chloride in acetone in the presence of a base at ice bath temperature to give the corresponding 1-acyl derivatives (equation 2). (TABLES II to V.) ##STR6## 
     R&#39;=--S--alkyl, --O--alkyl, aryl, alkyl. 
     Similarly the urea derivatives (TABLE V) were prepared by refluxing for 3 days in 1,4-dioxane. ##STR7## 
     R&#39;=--CH 3 , --CH 2  --CH 3 . 
    
    
     Following are illustrative synthesis procedures. 
     Isobutylideneiminoaminomaleonitrile 
     To a stirred suspension of 10.8 g (0.1 mole) diaminomaleonitrile in 100 ml of absolute ethanol 7.2 g (0.1 mole) of distilled isobutyraldehyde is added dropwise. The mixture is stirred at room temperature overnight to give a clean solution. Evaporate to dryness and stir the residue in cold water. Filter, wash with water and dry to give 11.5 g, mp 83°-85° (71%) whitish product. 
     2-Isopropyl-4,5-dicyanoimidazole 
     To a stirred mixture of 9.2 g (0.05 mole) of isobutylideneiminoaminomaleonitrile in 100 ml of dry benzene at 5° C. under dry conditions lead tetraacetate 25 g (0.057 mole) is added in parts while keeping the temperature at approximately 10° C. Let it warm to room temperature and stir overnight. Cool the mixture to approximately 10° C., filter wash with benzene, dry and stir the residue in 100 ml water. The aqueous mixture is acidified to approximately pH 4 and extracted with ethyl acetate. Dry and evaporate to give 4.5 g, mp 146°-49°, (49%) product. 
     Methyl 4,5-dicyanoimidazole-1-thiolcarboxylate 
     To a stirred ice cold solution of 4.5 g (0.038 mole) 4,5-dicyanoimidazole, triethylamine 4.2 g (0.042 mole), and 4.7 g (0.042 mole) of methylchlorothiolformate are added dropwise in succession. Let it stir for 2 hours in ice bath and at room temperature overnight. The mixture is then poured into ice water and dried to give 6.0 g, mp 131°-33° (83%) product. 
     Analytical sample recrystallized from hexane: white flakes mp 132°-34°. 
     Anal. Calcd. for C 7  H 4  N 4  OS; C, 43.74, H, 2.10; N, 29.15. Found: C, 43.36; H, 2.40; N, 29.41. 
     Methyl 2-methyl-4,5-dicyanoimidazole-1-carboxylate 
     Synthesis procedure and workup method are similar to those employed for the preparation of methyl 4,5-dicyanoimidazole-1-thiolcarboxylate. 
     White product m.p. 113°-15° (23%) 
     Anal. Calcd. for C 8  H 6  N 4  O 2  : C, 50.53; H, 3.18; N, 29.46. Found: C, 50.39; H, 3.39; N, 29.35. 
     1-(3&#39;-Chlorobenzoyl)-2-methyl-4,5-dicyanoimidazole 
     Synthesis procedure and work up method are similar to those employed for the preparation of methyl 4,5-dicyanoimidazole-1-thiolcarboxylate. 
     Yellow product (74%). Recrystallization from benzene-hexane yields yellowish crystals, m.p. 141°-42°. 
     Anal. calcd. for C 13  H 7  ClN 4  O: C, 57.69; H, 2.69; N, 20.70. Found: C, 57.62; H, 2.69; N, 20.96. 
     1-(N,N-Dimethylcarbamoyl)-4,5-dicyanoimidazole 
     To 50 ml of dry 1,4-dioxane 6.0 g (0.05 mole) of 4,5-dicyanoimidazole, 5.0 g (0.05 mole) of triethylamine and 6.0 g (0.055 mole) of dimethylcarbamoyl chloride are added in succession at room temperature. This mixture is stirred and refluxed for 3 days, cooled to room temperature and evaporated to dryness. The residue is stirred in 50 ml of ethyl acetate and 50 ml water. The organic layer is separated, washed, dried and evaporated to give 8 g. (85%) of white product. 
     Recrystallization from benzene-hexane yields white needles, m.p. 89°-90°. 
     COMBATING UNWANTED VEGETATION 
     The novel herbicides are effective when used both post- and pre-emergently. In commercial use the compounds are formulated as herbicidal compositions in combination with an inert diluent and a surface active agent. There is described below an illustrative procedure for herbicidal use of the compounds under controlled conditions in the greenhouse so as to obtain data on phytotoxic activity and selectivity. 
     1. Post Emergent Use 
     An aqueous dispersion of each active compound is prepared by combining 0.4 gram of the compound with about 4 ml of a solvent-emulsifier mixture (3 parts of a commercial polyoxyethylated vegetable oil emulsifier, 1 part xylene, 1 part kerosene) and then adding water, with stirring, to a final volume of 40 ml. 
     The species of plants on which each compound is to be tested are planted in 4-inch pots in a greenhouse. Ten to 18 days after emergence of the plants, three pots of each species are sprayed with an aqueous dispersion of the active compound prepared as described above, at a rate of 5 lb of active compound per acre and at a spary volume of 60 gallons per acre. Approximately 2 weeks after the spray application the plants are observed and the results rated according to the following schedule: 
     DEGREE OF EFFECT 
     0=no effect 
     1=slight effect (temporary injury) 
     2=moderate effect (some permanent injury) 
     3=severe effect (some plants died) 
     4=maximum effect (all plants died) 
     The same rating schedule is employed to judge pre-emergent results obtained according to the procedure below. 
     2. Pre-emergent Use 
     A solution of each active compound is prepared by dissolving 290 mg of the compound to be tested in 200 ml of acetone. Disposable expanded polystyrene trays about 21/2 inches deep and about 1 square foot in area are prepared and sprayed with the acetone solution at the rate of 10 lb of active chemical per acre of sprayed area and are then covered with about one-fourth inch of soil. Twenty-one days after seeding and treatment the plants are examined and herbicidal effects are rated according to the above schedule. 
     Both post-emergent and pre-emergent results which have been obtained with the herbicides are set forth in the following tables. 
     
                                           TABLE 1                                 
__________________________________________________________________________
HERBICIDAL USE OF COMPOUNDS OF THE FORMULA                                
 ##STR8##                                                                 
            m.p.       Digitaria                                          
                             Celosia                                      
                                  Bromis                                  
                                      Setaria                             
                                          Medicago                        
                                                Avena                     
                                                    Raphanus              
                                                         Beta             
Example     or         sanguinalis                                        
                             plumosa                                      
                                  inermis                                 
                                      italica                             
                                          sativa                          
                                                sativa                    
                                                    satovis               
                                                         vulgaris         
No.  R      b.p.   Type                                                   
                       Crabgrass                                          
                             Coxcomb                                      
                                  Brome                                   
                                      Millet                              
                                          Alfalfa                         
                                                Oats                      
                                                    Radish                
                                                         Sugarbeet        
__________________________________________________________________________
1    H      m.p. 168°-71°                                   
                   PRE 1     4    1   1   --    --  4    4                
                   POST                                                   
                       --    --   --  3   4     4   4    4                
2    CH.sub.3                                                             
            m.p. 224°-27°                                   
                   PRE 3     4    4   4   --    --  4    4                
                   POST                                                   
                       --    --   --  4   4     3   4    4                
3    CH.sub.2 CH.sub.3                                                    
            m.p. 182°-84°                                   
                   PRE 4     4    4   4   --    --  3    4                
                   POST                                                   
                       --    --   --  4   4     3   4    4                
4    CH(CH.sub.3).sub.2                                                   
            m.p. 146°-49°                                   
                   PRE 3     4    3   3   --    --  4    4                
                   POST                                                   
                       --    --   --  4   4     3   4    4                
5    C(CH.sub.3).sub.3                                                    
            m.p. 146°-48°                                   
                   PRE 3     4    4   4   --    --  4    4                
                   POST                                                   
                       --    --   --  4   4     4   4    4                
6    C.sub.6 H.sub.5                                                      
            m.p. 135°-37°                                   
                   PRE --    2    --  --  --    --  3    3                
                   POST                                                   
                       --    --   --  1   4     1   4    4                
7    C.sub.6 H.sub.4 Cl(m)                                                
            m.p. 223°-25°                                   
                   PRE --    1    1   4   --    --  1    3                
                   POST                                                   
                       --    --   --  --  1     1   3    4                
8    cyclopropyl                                                          
            m.p. 182°-4°                                    
                   PRE 4     4    4   4   --    --  4    4                
                   POST                                                   
                       --    --   --  4   4     4   4    4                
9    C.sub.2 H.sub.5 O                                                    
            m.p. 85°-86°                                    
                   PRE 2     3    4   3   --    --  4    4                
                   POST                                                   
                       --    --   --  1   4     3   4    4                
                   PRE                                                    
                   POST                                                   
                   PRE                                                    
                   POST                                                   
                   PRE                                                    
                   POST                                                   
__________________________________________________________________________
 
    
     
                                           TABLE II                                
__________________________________________________________________________
HERBICIDAL USE OF COMPOUNDS OF THE FORMULA                                
 ##STR9##                                                                 
                                   Celo-   Se-                            
                              Digitaria                                   
                                   sia-    taria                          
                                              Medi-   Raph-               
                                                          Beta            
                              sanguin-                                    
                                   plum-   ital-                          
                                              cago    anus                
                                                          vul-            
                  m.p.        alis osa Bromis                             
                                           ica                            
                                              sat-                        
                                                  Avena                   
                                                      sat-                
                                                          garis           
Ex.               or          Crab-                                       
                                   Cox-                                   
                                       inermis                            
                                           Mil-                           
                                              iva sativa                  
                                                      ovis                
                                                          Sugar-          
No.                                                                       
   R      R&#39;      b.p.    Type                                            
                              grass                                       
                                   comb                                   
                                       Brome                              
                                           let                            
                                              Alfalfa                     
                                                  Oats                    
                                                      Radish              
                                                          beet            
__________________________________________________________________________
10 H      CH.sub.3                                                        
                  m.p. 132°-34°                             
                          PRE 2    3   1   1  --  --  2   4               
                          POST                                            
                              --   --  --  -- 2   2   3   4               
11 H      CH.sub.2 CH.sub.3                                               
                  m.p. 79°-80°                              
                          PRE 4    4   4   4  --  --  4   4               
                          POST                                            
                              --   --  --  1  4   2   4   4               
12 H      C.sub.4 H.sub.9 (n)                                             
                  b.p.162°/                                        
                          PRE 2    3   1   1  --  --  1   4               
                  0.15 mm POST                                            
                              --   --  --  2  4   4   4   4               
13 CH.sub.3                                                               
          CH.sub.3                                                        
                  m.p. 102°-103°                            
                          PRE 4    4   4   4  --  --  4   4               
                          POST                                            
                              --   --  --  3  4   3   4   4               
14 CH.sub.3                                                               
          CH.sub.2 CH.sub.3                                               
                  m.p. 44°-45°                              
                          PRE 4    4   3   2  --  --  4   4               
                          POST                                            
                              --   --  --  1  4   3   4   4               
15 CH.sub.2 CH.sub.3                                                      
          CH.sub.3                                                        
                  m.p. 65°-67°                              
                          PRE 2    4   1   1  --  --  2   4               
                          POST                                            
                              --   --  --  4  4   3   4   4               
16 CH.sub.2 CH.sub.3                                                      
          CH.sub.2 CH.sub.3                                               
                  m.p. 43°-44°                              
                          PRE 3    3   1   2  --  --  2   4               
                          POST                                            
                              --   --  --  4  4   2   4   4               
17 CH.sub.2 CH.sub.3                                                      
          (CH.sub.2).sub.2 CH.sub.3                                       
                  b.p. 141°-42 °/                           
                          PRE 3    3   1   1  --  --  2   4               
                  0.1 mm  POST                                            
                              --   --  --  4  4   1   4   4               
18 CH.sub.2 CH.sub.3                                                      
          CH(CH.sub.3).sub.2                                              
                  b.p. 147°-149°/                           
                          PRE 2    3   2   2  --  --  3   4               
                  0.15 mm POST                                            
                              --   --  --  4  4   4   4   4               
19 CH(CH.sub.3).sub.2                                                     
          CH.sub.3                                                        
                  m.p. 79°-80°                              
                          PRE 4    4   4   4  --  --  --  --              
                          POST                                            
                              --   --  --  1  4   2   4   4               
20 CH(CH.sub.3).sub.2                                                     
           CH.sub.2 CH.sub.3                                              
                  b.p. 138°-40°/                            
                          PRE 2    3   1   3  --  --  4   4               
                  0.2 mm  POST                                            
                              --   --  --  3  4   3   4   4               
21 C.sub.6 H.sub.5                                                        
          CH.sub.3                                                        
                  m.p. 108°-10°                             
                          PRE --   2   --  -- --  --  3   3               
                          POST                                            
                              --   --  --  2  4   1   4   4               
22 C.sub.6 H.sub.5                                                        
          CH.sub.2 CH.sub.3                                               
                  m.p. 83°-85°                              
                          PRE 1    2   --  -- --  --  3   4               
                          POST                                            
                              --   --  --  1  4   1   4   4               
23 (CH.sub.3).sub.2 CH                                                    
          CH.sub.3                                                        
                  m.p. 79°-80°                              
                          PRE 4    4   4   4  --  --  4   4               
                          POST                                            
                              --   --  --  1  4   2   4   4               
24 cyclopropyl                                                            
          CH.sub.3                                                        
                  m.p. 100°-102°                            
                          PRE 4    4   4   4  --  --  4   4               
                          POST                                            
                              --   --  --  4  4   4   4   4               
25 (CH.sub.3).sub.2 CH                                                    
          CH.sub.3 CH.sub.2 CH.sub.2                                      
                  b.p. 141°-2°/                             
                          PRE 1    4   4   2  --  --  4   4               
          0.1 mm  POST    --  --   --  3   4  3   4   4                   
26 cyclopropyl                                                            
          CH.sub.3 CH.sub.2                                               
                  63°                                              
                          PRE 4    4   4   4  --  --  4   4               
                          POST                                            
                              --   --  --  4  4   4   4   4               
27 cyclopropyl                                                            
          CH.sub.3 CH.sub.2 CH.sub.2                                      
                  b.p. 170°/                                       
                          PRE 3    4   4   4  --  --  4   4               
                  0.1 mm  POST                                            
                              --   --  --  4  4   4   4   4               
28 C.sub.2 H.sub.5 O                                                      
          CH.sub.3                                                        
                  m.p. 141°-143°                            
                          PRE 3    3   4   2  --  --  4   4               
                          POST                                            
                              --   --  --  1  4   2   4   4               
29 C.sub.2 H.sub.5 O                                                      
          C.sub.2 H.sub.5                                                 
                  m.p. 101°-103°                            
                          PRE 2    4   4   1  --  --  4   4               
                          POST                                            
                              --   --  --  3  4   3   4   4               
                          PRE                                             
                          POST                                            
                          PRE                                             
                          POST                                            
                          PRE                                             
                          POST                                            
                          PRE                                             
                          POST                                            
__________________________________________________________________________
 
    
     
                                           TABLE III                               
__________________________________________________________________________
HERBICIDAL USE OF COMPOUNDS OF THE FORMULA                                
 ##STR10##                                                                
                            Digita-                                       
                            ria                                           
                            sangui-                        Beta           
                 m.p.       nalis                                         
                                Celosia                                   
                                     Bromis                               
                                         Setaria                          
                                             Medicago                     
                                                  Avena                   
                                                      Raphanus            
                                                           vulgaris       
Ex.              or         Crab-                                         
                                plumosa                                   
                                     inermis                              
                                         italica                          
                                             sativa                       
                                                  sativa                  
                                                      satovis             
                                                           Sugar-         
No. R      R&#39;    b.p.(°C.)                                         
                        Type                                              
                            grass                                         
                                Coxcomb                                   
                                     Brome                                
                                         Millet                           
                                             Alfalfa                      
                                                  Oats                    
                                                      Radish              
                                                           beet           
__________________________________________________________________________
30  CH.sub.3                                                              
           CH.sub.3                                                       
                 m.p. 113°-15°                              
                        PRE 2   4    1   2   --   --  4    4              
                        POST                                              
                            --  --   --  2   4    3   4    4              
31  CH.sub.2 CH.sub.3                                                     
           CH.sub.3                                                       
                 m.p. 68°-70°                               
                        PRE 1   3    1   1   --   --  1    4              
                        POST                                              
                            --  --   --  4   4    2   4    4              
32  CH.sub.2 CH.sub.3                                                     
           CH.sub.2 CH.sub.3                                              
                 b.p. 160°/                                        
                        PRE 2   3    1   2   --   --  2    4              
                 0.1 mm POST                                              
                            --  --   --  4   4    3   4    4              
33  (CH.sub.3).sub.2 CH                                                   
           CH.sub.3                                                       
                 m.p. 72°-74°                               
                        PRE 2   2    4   2   --   --  4    4              
                        POST                                              
                            --  --   --  4   4    4   4    4              
34  H      CH.sub.3                                                       
                 m.p. 51°-53°                               
                        PRE 1   4    2   1   --   --  2    4              
                        POST                                              
                            --  --   --  1   3    4   4    4              
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                                           TABLE IV                                
__________________________________________________________________________
HERBICIDAL USE OF COMPOUNDS OF THE FORMULA                                
 ##STR11##                                                                
                             Digita-                                      
                                 Celo-                                    
                             ria sia                                      
                             sangui-                                      
                                 plum-                     Beta           
                 m.p.    nalis                                            
                             osa Bromis                                   
                                     Setaria                              
                                         Medicago                         
                                             Avena                        
                                                  Raphanus                
                                                      vulgaris            
Ex.              or          Crab-                                        
                                 Cox-                                     
                                     inermis                              
                                         italica                          
                                             sativa                       
                                                  sativa                  
                                                      satovis             
                                                           Sugar-         
No.                                                                       
   R      R&#39;     b.p.    Type                                             
                             grass                                        
                                 comb                                     
                                     Brome                                
                                         Millet                           
                                             Alfalfa                      
                                                  Oats                    
                                                      Radish              
                                                           beet           
__________________________________________________________________________
35 CH.sub.3                                                               
          C.sub.6 H.sub.5                                                 
                 m.p. 102°-104 °                            
                         PRE 2   4   1   1   --   --  2    4              
                         POST                                             
                             --  --  --  3   4    2   4    4              
36 CH.sub.3                                                               
          C.sub.6 H.sub.5 Cl(m)                                           
                 m.p. 141°-42°                              
                         PRE 1   4   1   1   --   --  2    4              
                         POST                                             
                             --  --  --  3   4    2   4    4              
37 CH.sub.2 CH.sub.3                                                      
          C.sub.6 H.sub.5                                                 
                 m.p. 120°-22°                              
                         PRE 3   3   4   3   --   --  4    4              
                         POST                                             
                             --  --  --  2   4    1   2    4              
38 CH.sub.2 CH.sub.3                                                      
          C.sub.6 H.sub.4 Cl(m)                                           
                 m.p. 105°-107°                             
                         PRE 3   3   1   2   --   --  3    4              
                         POST                                             
                             --  --  --  4   4    2   4    4              
39 cyclopropyl                                                            
          CH.sub.3 CH.sub.2                                               
                 m.p. 56°-57°                               
                         PRE 4   4   4   4   --   --  4    4              
                         POST                                             
                             --  --  --  2   4    4   4    4              
40 CH.sub.3                                                               
          CH.sub.3 CH.sub.2                                               
                 m.p. 119°-120°                             
                         PRE 4   4   4   4   --   --  4    4              
                         POST                                             
                             --  --  --  1   4    3   3    4              
41 CH.sub.3 CH.sub.2                                                      
          CH.sub.3 CH.sub.2                                               
                 m.p. 64°-69°                               
                         PRE 2   4   2   1   --   --  4    4              
                         POST                                             
                             --  --  --  1   4    2   4    4              
__________________________________________________________________________
 
    
     
                                           TABLE V                                 
__________________________________________________________________________
 HERBICIDAL USE OF COMPOUNDS OF THE FORMULA                               
 ##STR12##                                                                
Ex-          m.p.       Digitaria                                         
                              Celosia                                     
                                   Bromis                                 
                                       Setaria                            
                                           Medicago                       
                                                Avena                     
                                                    Raphanus              
                                                         Beta             
ample        or         sanguinalis                                       
                              plumosa                                     
                                   inermis                                
                                       italica                            
                                           sativa                         
                                                sativa                    
                                                    satovis               
                                                         vulgaris         
No. R   R&#39;   b.p.   Type                                                  
                        Crabgrass                                         
                              Coxcomb                                     
                                   Brome                                  
                                       Millet                             
                                           Alfalfa                        
                                                Oats                      
                                                    Radish                
                                                         Sugarbeet        
__________________________________________________________________________
42  CH.sub.3                                                              
        C.sub.6 H.sub.5                                                   
             m.p. 138°-40°                                  
                    PRE 1     4    1   1   --   --  1    4                
                    POST                                                  
                        --    --   --  4   4    1   3    4                
__________________________________________________________________________
 
    
     
                                           TABLE VI                                
__________________________________________________________________________
HERBICIDAL USE OF COMPOUNDS OF THE FORMULA                                
 ##STR13##                                                                
                            Digitaria                                     
                                 Celosia                                  
                            Sangui-                                       
                                 plu-                      Beta           
                m.p.        nalis                                         
                                 mosa                                     
                                     Bromis                               
                                         Setaria                          
                                             Medicago                     
                                                  Avena                   
                                                      Raphanus            
                                                           vulgaris       
Ex.             or          Crab-                                         
                                 Cox-                                     
                                     inermis                              
                                         italica                          
                                             sativa                       
                                                  sativa                  
                                                      satovis             
                                                           Sugar-         
No.                                                                       
   R      R&#39;    b.p.    Type                                              
                            grass                                         
                                 comb                                     
                                     Brome                                
                                         Millet                           
                                             Alfalfa                      
                                                  Oats                    
                                                      Radish/             
__________________________________________________________________________
                                                      beet                
43 H      CH.sub.3                                                        
                m.p. 89°-90°                                
                        PRE 1    3   1   1   --   --  2    4              
                        POST                                              
                            --   --  --  2   4    2   4    4              
44 H      CH.sub.2 CH.sub.3                                               
                m.p.118°-21°                                
                        PRE 1    3   1   1   --   --  2    3              
                        POST                                              
                            --   --  --  2   4    1   4    4              
45 CH.sub.3                                                               
          CH.sub.3                                                        
                m.p. 90°-91°                                
                        PRE 1    2   1   2   --   --  2    4              
                        POST                                              
                            --   --  --  3   4    3   3    4              
46 CH.sub.2 CH.sub.3                                                      
          CH.sub.3                                                        
                b.p.145°-46°/                               
                        PRE 1    4   1   1   --   --  2    4              
                0.15 mm POST                                              
                            --   --  --  3   4    1   2    4              
47 CH.sub.2 CH.sub.3                                                      
          CH.sub.2 CH.sub.3                                               
                b.p.189°-90°/                               
                        PRE --   2   1   1   --   --  1    4              
                0.2 mm  POST                                              
                            --   --  --  3   4    1   3    4              
48 (CH.sub.3).sub.2 CH                                                    
          CH.sub.3                                                        
                m.p. 72°-74°                                
                        PRE 0    1   3   1   --   --  3    4              
                        POST                                              
                            --   --  --  2   4    2   4    4              
49 cyclopropyl                                                            
          CH.sub.3                                                        
                m.p.120°-123°                               
                        PRE 2    4   4   1   --   --  4    4              
                        POST                                              
                            --   --  --  0   4    1   4    4              
__________________________________________________________________________
 
    
     To further illustrate the properties of the herbicides of this invention, there are presented in the following tables the results of herbicidal use of two specific compounds according to the procedures described above on a larger number of species and at various low rates of application. These two compounds have proved to be particularly useful for post-emergent control of weeds in such crops as corn, peanuts and soybeans, either alone or in combination with other herbicides. 
     
                                           TABLE VII                               
__________________________________________________________________________
HERBICIDAL USE ON 24 SPECIES                                              
              ##STR14##                                                   
                                  ##STR15##                               
             (No. 20)            (No. 15)                                 
             PRE       POST      PRE       POST                           
PLANT SPECIES                                                             
             3 lb/A                                                       
                  1 lb/A                                                  
                       3 lb/A                                             
                            1 lb/A                                        
                                 3 lb/A                                   
                                      1 lb/A                              
                                           3 lb/A                         
                                                1 lb/A                    
__________________________________________________________________________
Xanthium pensylvanicum                                                    
Cocklebur    0    0    4    2    0    0    4    4                         
Chenopodium album                                                         
Lambsquarters                                                             
             1    0    4    3    1    1    4    4                         
Ipomea purpurea                                                           
Morning glory                                                             
             0    0    4    3    0    0    4    3                         
Amaranthus retroflexus                                                    
Pigweed      1    0    2    2    1    1    4    4                         
Polygonum convolvulus                                                     
Wild Buckwheat                                                            
             0    0    4    4    0    0    4    4                         
Brassica kaber                                                            
Wild Mustard 0    0    4    2    0    0    4    2                         
Echinochloa crusgalli                                                     
Barnyard grass                                                            
             0    0    1    0    0    0    2    1                         
Digitaria sanguinalis                                                     
Crabgrass    0    0    1    0    0    0    2    1                         
Bromus tectorum                                                           
Downy Brome  0    0    1    0    0    0    1    0                         
Setaria faberii                                                           
Giant Foxtail                                                             
             0    0    2    0    0    0    3    1                         
Setaria viridis                                                           
Green Foxtail                                                             
             0    0    2    0    0    0    4    4                         
Cuperus esculentis                                                        
Nutsedge     0    0    0    0    0    0    0    0                         
Sorghum bicolor                                                           
Shatter Cane 0    0    0    0    0    0    4    0                         
Avena fatua                                                               
Wild Oats    0    0    2    0    0    0    1    0                         
Medicago sativa                                                           
Alfalfa      0    0    4    1    1    0    4    4                         
Gossypium herbaceum                                                       
Cotton       0    0    4    3    0    0    4    3                         
Arachis hypogaea                                                          
Peanut       0    0    1    1    0    0    2    1                         
Soja max                                                                  
Soybean      0    0    4    1    0    0    3    1                         
Beta vulgaris                                                             
Sugar Beets  0    0    4    4    0    0    4    4                         
Lycopersicum esculentum                                                   
Tomato       0    0    4    4    0    0    4    4                         
Zea mays                                                                  
Corn         0    0    0    0    0    0    1    0                         
Sorghum vulgare                                                           
Grain Sorghum                                                             
             0    0    0    0    0    0    2    0                         
Oryza sativa                                                              
Rice         0    0    2    1    0    0    2    1                         
Triticum aestivum                                                         
Wheat        0    0    2    0    0    0    2    0                         
__________________________________________________________________________
 
    
     
                                           TABLE VIII                              
__________________________________________________________________________
 POST-EMERGENCE USE AT LOW RATES OF APPLICATION                           
PLANT SPECIES                                                             
Compound                                                                  
      Rate                  Soy-   Velvet                                 
                                       Smart                              
                                           Jimson                         
                                               Sickle                     
                                                   Morning                
No.   lb/A                                                                
         Pigweed                                                          
               Alfalfa                                                    
                   Tomato                                                 
                        Cotton                                            
                            bean                                          
                               Peanut                                     
                                   leaf                                   
                                       weed                               
                                           weed                           
                                               pod glory                  
                                                        Cocklebur         
__________________________________________________________________________
15    2  4     4   4    4   3  1   4   4   4   4   4    4                 
      1  4     3   4    4   2  0   4   4   4   --  4    4                 
      1/2                                                                 
         3     3   3    3   1  0   4   3   4   --  3    4                 
      1/4                                                                 
         3     3   4    2   1  0   4   4   4   --  3    4                 
20    2  4     4   4    4   3  1   4   4   4   4   4    4                 
      1  4     3   4    2   1  0   4   4   4   4   4    4                 
      1/2                                                                 
         2     3   1    3   1  0   4   4   4   2   3    4                 
      1/4                                                                 
         3     3   4    2   1  0   4   4   4   --  2    3                 
__________________________________________________________________________