CH574712A5 - O-alkyl-s-alkyl-o-nitrophenyl thiophosphates - with pesticidal activity - Google Patents

Abstract

Cpds. of formula (I): (where R1 is Me or Et; R2 is n-Pr, n-Bu or n-pentyl; R3 is H, Me or Cl) are insecticides, acaricides and nematocides, and also agricultural virucides, bactericides and fungicides and plant regulators. They are pref. prepd. by reacting R1O(R2S)POCl with a cpd. (II): (where M is H, a monovalent metal, NH4 or tetraalkylammonium), in the presence of an acid binder when M = H.

Description

  

  
 



   The present invention relates to pesticides containing a nitrophenylthiol phosphoric acid ester as the active component, and their use in pest control.



   The Nitrophenylthiolphosphorsäureester have the For mell
EMI1.1
 wherein
R1 methyl or ethyl and
R2 denotes n-propyl, n-butyl or n-pentyl.



   Because of their action, compounds of the formula I are preferred in which
R1 ethyl and
R2 denotes n-pentyl.



   The compounds of the formula I can be prepared by the following methods known per se:
EMI1.2

EMI1.3


<tb> acid-binding
<tb> <SEP> v <SEP> I
<tb> <SEP> means
<tb>
EMI1.4

In the formulas II, III and IV, R1 and R2 have the meaning given for the formula I and Me stands for an alkali metal, in particular sodium or potassium, or an ammonium group, such as. B. the groups (R4) 3-NH, in which R4 is hydrogen or alkyl.



   Suitable acid-binding agents are: tertiary amines, e.g. B. trialkylamines, pyridine, pyridine bases, dialkylanilines; inorganic bases such as hydrides, hydroxides; Carbonates and bicarbonates of alkali and alkaline earth metals.



  In the reactions it is sometimes necessary to use catalysts, such as. B. copper or copper chloride to be used. Processes 1 and 2 are carried out at a reaction temperature between 0 130 C, under normal pressure and in solvents or diluents.



   Suitable solvents or diluents are, for. B.



  Ethers and ethereal compounds such as diethyl ether, dipropyl ether, dioxane, tetrahydrofuran; Amides such as N, N-dialkylated carboxamides; aliphatic, aromatic and halogenated hydrocarbons, in particular benzene, toluene, xylenes, chloroform, chlorobenzene; Nitriles such as acetonitrile; DMSO, ketones such as acetone, methyl ethyl ketone, water.



   The starting materials of the formulas II to IV can be prepared analogously to known methods described.



   The compounds of the formula I are suitable for combating various types of plant and animal pests.



     Surprisingly, the compounds of formula I have better insecticidal and acaricidal properties than known, analogous compounds and can be used against all stages of development, such as. B. eggs, larvae, pupae, nymphs and adults, are used by insects and representatives of the order Akarina, such as. B. against insects of the families: Tettigoniidae, Gryllidae, Gryllotalpidae, Blattidae, Reduviidae, Pyrrhocoridae, Cimicidae, Delphacidae, Aphididae, Diaspididae, Pseudococcidae, Scarabaeidae, Dermestymaline, Termalymaline T, Crysulidae, Crysulidae, Chrysulidae, Crysulidae, Crysulidae , Tripulidae, Stomoxydae, Trypetidae, Muscidae, Calliphoridae and Pulicidae, as well as acarids of the families Ixodidae, Argasidae, Tetranychidae and Dermanyssidae.



   The insecticidal or acaricidal effect can be significantly broadened by adding other insecticides and / or acaricides and adapted to given circumstances.



   example 1
O-ethyl-S-n-propyl-O- (2-nitro-4-chlorophenyl) -thiolphosphoric acid ester
18.1 g of 2-nitro-4-chlorophenol are dissolved in 150 ml of benzene, then 13.3 g of triethylamine are added. At 10-15 ° C., 26.4 g of O-ethyl-Sn-propylchlorothiolphosphoric acid ester are added dropwise with constant stirring. To
Stirring for 12 hours at room temperature is washed with water, 3% Na2CO3 solution and again with water and dried over anhydrous sodium sulfate. The benzene is distilled off.

  After molecular distillation of the residue at 135 C / 0.001 Torr, the compound of the formula is obtained
EMI1.5
   nD23: 1.5409
The following connections are also established in the same way:
O-ethyl-S-n-pentyl-O- (2-chloro-4-nitrophenyl) -thiolphosphoric acid ester
O-Ethyl-S-n-pentyl-O- (2-nitro-4-chlorophenyl) -thiol phosphoric acid ester O-ethyl-S-n-pentyl- (3-nitro-4-chlorophenyl) -thiol phosphoric acid ester
Example 2
A. Insecticidal feed poison effect
Tobacco and potato plants were sprayed with a 0.05% aqueous active substance emulsion (obtained from a 10% emulsifiable concentrate).



   After the covering had dried on, the tobacco plants were populated with owl caterpillars (Spodoptera littoralis) and the potato plants with Colorado beetle larvae (Leptinotarsa decemlineata). The experiment is carried out at 24 C and 60% relative humidity.



   In the above test, the compounds according to Example 1 showed a food poison action against Spodoptera littoralis and Leptinotarsa decemlineata.



   Example 3
Effect against Chilo suppressalis
6 rice plants of the Caloro variety were transplanted into plastic pots with an upper diameter of 17 cm and raised to a height of about 60 cm. The infestation with chilo suppressalis larvae (L1; 3-4 mm long) took place 2 days after the addition of the active ingredient in granulate form (application rate 8 kg active ingredient per hectare) in the paddy water. The insecticidal activity was evaluated 10 days after the granules had been added.



   The compounds according to Example 1 were effective against Chilo suppressalis in the above test.



   Example 4
Effect against soil insects
Sterilized compost soil was mixed homogeneously with a wettable powder containing 25% active ingredient, so that an application rate of 8 kg of active ingredient per hectare resulted.



   With the treated soil, young zucchetti plants (Cucumis pepo) were potted in plastic pots (three plants per pot with a diameter of 7 cm). Each pot was immediately afterwards with 5 Aulacophora femoralis larvae, respectively. Pachnoda or Chortophila larvae infected. The control was carried out 4, 8, 16 and 32 days after the larvae were inserted.



   At 80-100% kill after the first control, a new infestation was carried out with 5 larvae each in the same soil pattern with 3 new courgette plants. If the effect was less than 80%, the remaining animals remained in the test soil until the next control. A substance caused 100% at an application rate of 8 kg / ha. Killing, then a follow-up test with 4 resp. 2 kg active ingredient / ha.



   In the above test, the compounds according to Example 1 showed activity against Aulacophora femoralis, Pachnoda and Chlortophila larvae.



   Example 5
Effect against ticks
A. Rhipicephalus bursa
5 adult ticks or 50 tick larvae were counted in a glass tube and immersed for 1 to 2 minutes in 2 ml of an aqueous emulsion from a dilution series with 100, 10, 1 and 0.1 ppm test substance each. The tube was then closed with a standardized cotton ball and turned upside down so that the active ingredient emulsion could be absorbed by the cotton wool.



   The evaluation was carried out after 2 weeks for the adults and after 2 days for the larvae. Two repetitions were run for each attempt.



   B. Boophilus microplus (larvae)
With an analogous dilution series as in test A, 20 sensitive resp. OP-resistant larval experiments were carried out. (The resistance relates to the tolerance of Diazinon).



   The compounds according to Example 1 were active in these tests against adults and larvae of Rhipicephalus bursa and sensitive, respectively. OP-resistant larvae of Boophilus microplus.



   Example 6
Acaricidal effect
Phaseolus vulgaris (French beans) were coated with an infected piece of leaf from a mass cultivation of Tetranychus urticae 12 hours before the test for acaricidal activity.

 

  The overflowing mobile stages were dusted with the emulsified test preparations from a chromatography atomizer so that the spray mixture did not run off.



  After two to 7 days, larvae, adults and eggs were evaluated under the binocular for living and dead individuals and the result was expressed as a percentage. During the holding time, the treated plants stood in greenhouse cabins at 25 C.



   In the above test, the compounds according to Example 1 were effective against adults, larvae and eggs of Tetranychus urticae.



   PATENT CLAIM 1
Pesticides containing as active component a compound of the formula (I)
EMI2.1
 wherein
R1 methyl or ethyl and
R2 denotes n-propyl, n-butyl or n-pentyl.

 

Claims (1)

SUBClaim Agent according to claim I, containing a compound of the formula I in which R1 ethyl and R2 denotes n-pentyl. PATENT CLAIM II Use of an agent according to claim I for combating insects and representatives of the order Akarina.