IL25831A - Nematocidal compositions containing esters of o-ethyl-s,s-dipropyl-dithiolphosphoric acid - Google Patents

Description

compositions containing esters of BAYER 2 The present invention is concerned compositions containing acid which hare a nematocidal and to a method of combating nematodes using these From Patent Specification there are inter acid esters which have nematocida and acid esters are not described in the said Patent These two last mentioned compounds have the general 0 wherein is an or with the products of analogous structure and the same direction of which are known from the mentioned Patent the acid esters of formula X above not only exhibit very good nematocidal properties bu are also characterised by a substantially higher nematocidal power and by a lower toxicity towards In comparison with acid which is a commercially available the compounds according to the present invention have a substantially capacity of penetrating into the Due to this threefold increased penetrating power and disperslbility in the a complete destruction of the is even if the soil is only incompletely mixed with the nematocide On account of these superior the cm und of the sent invntion con tit valuab The compounds of formula I above are obtained in a smooth and uniform reaction and in very good when an acid ester dihalide of the general formulas in which Hal is a halogen preferably a chlorine or bromine is reacted with or in the presence of an agent or with the corresponding alkali metal or ammonium The course of the reaction according to the present invention can be illustrated by the following equations In this and Hal have the same meanings as and Me represents a hydrogen atom or an alkali metal preferably a sodium or potassium or an ammonium grou when Me is a hydrogen a the reaction is carried out the presence of an acid ester required as starting materials for carrying out the process described especially the corresponding are known from the literature they can also be produced in large amounts by the reaction of phosphorus oxyhalldes wit preferably without the concurrent use of an acid reaction according to the present invention is preferably carried out in the presence of solvents or Virtually all inert organic solvents can be used for this optionally chlorinated aliphatic or aromatic such as methylene and trichloro carbon xylenes and as well as such as diethyl ether and dibutyl dioxan and and low molecular weight aliphatic for methyl ethyl methyl isopropyl ketone and methyl isobutyl and such as acetonitrile and have proved to be particularly All customary agents can be used as acid for alkali metal bonates and but also tertiary aromatic or heterocyclic such as and According to a special method of out the the alkali metal or salts of the concerned are first prepared and subsequently further reacted with the phosphoric acid The process according to the present invention can be carried out within a fairly wide range of In the reaction takes place between and the boiling point of the reaction preferably in the range from 40 to The reaction is usually carried out at atmospheric pressure but it is sometimes advantageous or even necessary to work under increased for in order to attain a higher reaction temperature in the case where a low boiling solvent is The limits of the pressure to be applied are determined by the partial pressure of the solution at the temperature The reaction components are generally used in a ratio of one mol acid ester dihalide to 2 or but the latter may also be used in In the order in which the starting materials are mixed is of no importance for the success of the process but it is preferred to add the acid ester dihalide dropwise to a viously prepared suspension of the alkali metal or ammonium mercaptide in an inert it has proved to be advantageous to tinue stirring the reaction mixture for some time minutes to 3 hours after the components have been possibly while heating at the stated Working up of the reaction mixture is carried out in known manner by pouring the reaction mixture into extracting the reaction which precipitates in the form of an with an appropriate inert drying the organic distilling off the solvent distilling the remaining acid new compounds of the present invention are colourless to slightly yellow oils which can be distilled under strongly reduced pressure without As already mentioned the compounds according to the present invention have outstanding nematocidal A 9540 properties but only a low toxicity towards animals and be used for combating especially the phyto athogenic These essentially include the leaf nematodes such as the chrysanthemum eialworm the strawberry f and the rice eelworm stalk nematodes such as the stem eelworm root gall nematodes such as arenaria and nematodes such as the potato nematode and the beet nematode and also root such as of the species Xiphinema and For use as the active compounds according to the present invention can be converted into the usual such as pastes and These are prepared in known for by mixing the active compounds with liquid and solid diluents and optionally with the use of emulsifying agents dispersing In the case of the use of water as an organic solvents for also be used as auxiliary As liquid diluents or there are preferably used aromatic such as xylenes or chlorinated aromatic such as such as mineral oil such as methanol or and strongly polar such as dimethyl sulphoxide or dimethyl as well as As solid diluents or there are preferably ground natural such as talc and ground synthetic minerals such as dispersed silicic acid or Preferred examples of emulsifying agents include and anionic such as fatty acid alcohol for alkyl aryl polyglycol alkyl sulphonates and aryl preferred examples of dispersing agents include lignin sulphite waste liquors and methyl The active compounds according to the present vention be present in the formulations in admixture with known active The formulations generally contain between and preferably between and per cent by weight of active The active compounds can be used as in the form of their formulations or of the preparations made therefrom for such as emulsifiable spray soluble dusts and granules ready for They are applied in the usual for by vaporising or soil according to another feature of the present there is provided a method of combating wherein there is applied to a nematode habitat a compound of general formula alone or in admixture with a solid or liquid diluent Example A Critical concentration test Test Meloidogyne parts by weight dimethyl 10 parts by weight benzylhydroxydiphenyl poly lycol ether To produce a suitable 1 part by weight of the active compound is mixed with the stated amount of the stated amount of emulsifier is added to this premixture and the concentrate so obtained is diluted with water to the desired This preparation of the active substance is mately mixed with soil which is heavily infested with the test The concentration of the active compound in the preparation is practically of no Only the amoun of active substance per unit volume of soil is this is given in The soil is filled into sown with lettuce and then kept at a greenhouse temperature of after 4 the lettuce roots are examined for infestation by nematodes and the degree of effectiveness is determined as a The degree of effectiveness is when infestation is completely prevented and when the infestation is exactly the same as that of the control plants in untreated soil which has been infested in the same The active compounds the amounts applied and the results obtained can be seen from the following Table Le A 9540 TABLE A concentration Compound Degree of effectiveness in with amounts of 40 20 10 5 ppm 100 100 100 100 to to from atent from from Patent 90 50 0 Le A 9540 9 Example Determination of penetrating power The penetrating power is determined in open land in small The amount applied is 10 active compound per square The preparation is evenly sprayed but not worked into the After 3 samples of the soil are taken in the form of layers of 2 thickness and the nematodes of the species Heterodera rostochiensia contained in the samples are examined for their capacity of infesting In the following Table the depth is stated to which the preparation has penetrated in the soil or where living nematodes can no longer be TABLE B Compound Depth of penetration to to from Patent 10 from Patent A 9540 following Examples are given for the purpose of illustrating the present Example 1 grams in 300 xylene are mixed with powdered potassium The mixture is subsequently boiled under reflux for 2 with vigorous and the solvent and liberated water are then distilled off under reduced The ing dry potassium isopropyl mercaptide is suspended in 300 acid di chloride are added dropwise to this suspension at 40 to while and the reaction mixture is stirred at room temperature After pouring the mixture into the precipitated oil is taken up with the benzene solution is washed with dried over anhydrous sodium sulphate and the benzene is evaporated under reduced pressure and the residue subjected to fractional 52 grams of acid ester are obtained in the form of a yellow oil of boiling point 96 to Example 2 0 grams sodium metal are divided as finely as possible in 150 boiling toluene by stirring The is allowed to cool while vigorous stirring is until the molten sodium has dified in the form of small grams ubs added dropwise to the reaction mixture at The temperature of the mixture is kept within the range of 70 to by external If sodium metal is still present in the mixture after stirring at for 45 a few more drops of are added and the mixture is subsequently treated dropwise at to with acid dichloride dissolved in 30 The reaction mixture is heated at for 30 minutes to complete the then washed with water until the reaction is dried and evaporated under reduced The residue is subjected to fractional distillation and of of acid ester are obtained in the form of a slightly yellow oil which boils at 79 to mm 0 54 grams acid ester dissolved in 100 diethyl are added dropwise at 0 to within the course of 50 to a solution of and 100 anhydrous triethylamine in 200 dry diethyl Triethyl ammonium chloride is thereby The reaction mixture is subsequently heated at boiling temperature under reflux for 2 hours and stirred at room temperature After the hydrochloride formed has been washed out with the ether solution is the residue is distilled under reduced pressure and 23 of acid ester are obtained in the insufficientOCRQuality

Claims (1)

1. compositions containing a compound of the formulas 0 wherein R is an or isopropyl in admixture with a solid or liquid diluent or Method of combating wherein there is applied to a nematode habitat a compound of formula I in Claim alone or in admixture with a solid or liquid diluent or A method of f soil from nematodes or of rendering soil resistant to infestation by wherein soil is treated with a compound of formula I in Claim alone or in admixture with a solid or liquid diluent or carrier whenever treated with a compound of formula I in Claim alone or in admixture with a solid or liquid diluent or insufficientOCRQuality