Abstract:
Dimethylcarbamyltriazole insecticides of the type disclosed in U.S. Pat. Nos. 4,054,664 and 4,066,774 are stabilized against decarbamylation in the presence of clay minerals, either in the soil or in pesticide formulations by incorporating with the dimethylcarbamyltriazole at least one part by weight of nonionic aliphatic polyol per 10 parts of insecticide.

Description:
DESCRIPTION OF THE INVENTION 
     A new class of insecticides and miticides, as disclosed in U.S. Pat. Nos. 4,054,664 and 4,066,774 are dimethylcarbamyl triazoles. Although these compounds are not carbamate esters, it is assumed that the insecticidal activity is attributable to the reaction of labile dimethylcarbamyl groups with specific enzymes, according to the accepted theory of the action of carbamate esters. The reactivity of the dimethylcarbamyl group, which is believed to be of critical importance with respect to utility is also the principal disadvantage when these compounds are formulated as granules with clays, or when applied to the soil to kill soil-borne insect pests. It has been discovered that exposure of the insecticides to finely divided argillaceous substances, such as various clays, causes the decarbamylation of the triazoles within a relatively short time at ordinary ambient temperatures. Some dimethylcarbamyltriazoles of the structural formula ##STR1## are particularly useful in combating insect larvae in the soil and as they are very toxic substances, it is more convenient to formulate these insecticides as clay-based granules of low concentration, containing five to ten percent active ingredients. In granular formulations of this type the insecticides will decompose at ambient or room temperature. The decomposition has been monitored by means of nuclear magnetic resonance and it has been found that the following reaction occurs: ##STR2## I have found that the addition of non-ionic aliphatic polyols to the clay granules stops the decarbamylation of the active ingredient, thereby stabilizing the material in the granular formulation. 
    
    
     The stabilizing effect has been demonstrated by the procedure described below. 
     PROCEDURE 
     The control sample was prepared by dissolving 5.0 g of active ingredient in acetone, then adding the resulting solution to 45.0 g of Florex clay granules. The acetone was evaporated, yielding a 10% formulation on clay. A sample was taken and analyzed by NMR. The remainder of the sample was placed in an oven at 50° C. Samples were taken at 1, 2, 4 and 8 week intervals. 
     The stabilized samples were prepared by dissolving the stabilizing agent in acetone, then adding the solution to the clay. The acetone was then removed and an acetone solution of the active ingredient was added to the clay. The acetone was then evaporated. A sample was taken and analyzed by NMR. The remainder of the material was placed in an oven at 50° C. Samples were taken at 1, 2, 4 and 8 week intervals. 
     The first table summarizes the results with the first of two triazoles, in which R is tert.butyl and R 1  is allyl, on different clays and additives stored in an oven at 50° C. The second table summarizes the results with a second triazole in which R is tert.butyl and R 1  is methyl. The third table summarizes the results when propylene glycol and active ingredient are added to the clay at the same time. 
     
                       TABLE II______________________________________Triazole No. 2(10% by wt. on clay)              % Product RemainingType Clay          Time in Weeks at 50° C.No.  Carrier   Additive    0    1    2    4    8______________________________________1    Florex    None        100   67   54   22  --2    Florex    5% Propylene                      100  100  100  100  --          glycol______________________________________ 
    
     
                                           TABLE I__________________________________________________________________________Triazole No. 1(10% by wt. on clay)                        % Product Remaining        Additive        Time in Weeks at 50° C.No.   Type Clay Carrier        (% by wt. of total composition)                        0  1  2  4  8__________________________________________________________________________1  Florex    None            100                            71                               56                                  32                                     72  Florex    5% Propylene glycol                        100                           100                              100                                 100                                    1003  Florex    4% Propylene glycol                        100                           100                              100                                 100                                    1004  Florex    3% Propylene glycol                        100                           100                              100                                 100                                    1005  Florex    2% Propylene glycol                        100                           100                              100                                 100                                    856  Florex    1% Propylene glycol                        100                           100                               84                                  66                                    547  Bentonite None            100                            89                               83                                  82                                    818  Bentonite 5% Propylene glycol                        100                           100                              100                                 100                                    889  Bentonite 4% Propylene glycol                        100                           100                              100                                 100                                    8910 Bentonite 3% Propylene glycol                        100                           100                              100                                 100                                    8511 Bentonite 2% Propylene glycol                        100                           100                              100                                 100                                    8812 Bentonite 1% Propylene glycol                        100                           100                              100                                  88                                    8113 Florex    5% Maracarb N-1*                        100                           100                              100                                  81                                    6714 Florex    5% Hexamethylenetetramine                        100                            82                               88                                  67                                    4915 Florex    5% Pluronic L-44*                        100                           100                              100                                 100                                    10016 Florex    5% 2-aminoethanol                        100                            40                               34                                  19                                    6117 Florex    5% Ethylene glycol                        100                           100                              100                                 100                                    8118 Florex    5% Tween 20*    100                           100                              100                                 100                                    8319 Florex    5% Urea         100                           100                              100                                  85                                    7220 Florex    5% NH.sub.3      84                            53                               42                                  21                                    30__________________________________________________________________________ *Pluronic L44 is a block copolymer resulting from condensing an average o 47 moles of ethylene oxide with a propylene oxidepropylene glycol condensation product. Tween 20 is a product of condensation of an average of 20 moles of ethylene oxide with sorbitan monolaurate. Maracarb N1 is a salt of a low molecular weight lignosulfonic acid, containing some carbohydrate material. 
    
     
                                           TABLE III__________________________________________________________________________Simultaneous Addition of Triazole and Polyol to Clay(10% triazole by wt. on clay)                        % Product Remaining                        Time in Weeks at 50° C.No.   Type Clay Carrier        Triazole             Additive   0  1  2  4  8__________________________________________________________________________1  Florex    No. 1             5% Propylene glycol                        100                           100                              100                                 100                                    1002  Florex    No. 2             5% Propylene glycol                        100                           100                              100                                 100                                    --__________________________________________________________________________