1113-02-6

Usage

Uses

Used in Agricultural Industry:
O,O-Dimethyl S-methylcarbamoylmethyl phosphorothioate is used as an insecticide for the control of sucking insects and mites in a wide variety of crops. Its application helps protect plants from damage caused by these pests, ensuring a healthy and productive yield.
Used in Pesticide Combinations:
O,O-Dimethyl S-methylcarbamoylmethyl phosphorothioate is also used in combination with other carboxamides and pesticides to create insecticidal, acaricidal, and fungicidal formulations. These combinations enhance the overall effectiveness of pest control measures, targeting a broader range of pests and providing more comprehensive protection for crops.

Contact allergens

Contact dermatitis from omethoate-dimethoxon is rare.

Metabolic pathway

Omethoate is the P=O analogue (oxon) of dimethoate. Dimethoate is metabolised via oxidative desulfuration to omethoate which is the active anti-acetylcholinesterase metabolite. This biotransformation occurs in all media: hence the metabolic pathways of both compounds have much in common. However, degradative pathways acting directly on dimethoate such as O-demethylation, N-demethylation and hydrolysis of the amide function mean that the balance between activation and degradative metabolism will influence their respective selective toxicities. In mammals there are two main routes of degradation: (i) glutathione transferase mediated O-demethylation (ii) hydrolysis to N-methylthioglycolamide which is S-methylated by S-adenosylmethionine and subsequently thiooxidised. In soil and plants the N-methylthioglycolamide moiety formed from the hydrolysis of omethoate undergoes a complex series of C1, C2 and C3 biotransformations ultimately leading to oxalate and citrate respectively and total degradation to C02. The information reported below is derived largely from an evaluation prepared by the UK MAFF Pesticide Safety Directorate (PSD, 1993).

Metabolism

Orally administered omethoate to rats is rapidly metabolized and excreted in the urine; the main metabolites are O-demethylomethoate and N-methyl-2- methylsulfinylacetamide. O-Demethylation and hydrolysis of the P?S bond are main degradation routes both in mammals and plants. Omethoate is rapidly degraded in soils with DT50 of a few days.

Toxicity evaluation

The acute oral LD50 for rats is about 25 mg/kg. Inhalation LC50 (4 h) for rats is 0.3 mg/L air. ADI is 0.3 μg/kg b.w.

Degradation

Omethoate was slowly hydrolysed in acidic media but more rapidly under alkaline conditions. The half-lives for hydrolysis at pH 4,7, and 9 were 102 days, 17 days and 28 hours, respectively (PM). Omethoate does not absorb light at wavelengths above 250 nm and it is thus unlikely to be subject to photodecomposition. An aqueous solution of omethoate was irradiated for 14 hours with a high pressure filtered mercury vapour lamp without detectable photolysis occurring (PSD, 1993).

InChI:InChI=1/C5H12NO4PS/c1-6-5(7)4-12-11(8,9-2)10-3/h4H2,1-3H3,(H,6,7)

Upstream product

• 96-30-0 chloroacetylmethylamide 
• 60-51-5 Dimethoate 
• 23754-87-2 Natriumsalz des Thiophosphorsaeure-O,O-dimethylesters 
• 57212-78-9 O,O-Dimethyl-S-(methoxycarbonylmethyl)-thiophosphorsaeure 
• 74-89-5 methylamine 
• 20938-74-3 mercapto-acetic acid methylamide 
• 868-85-9 Dimethyl phosphite 

Downstream Products

• 512-56-1 trimethyl phosphite 
• 152-20-5 O,O,S-trimethyl phosphorothioate 
• 20938-74-3 mercapto-acetic acid methylamide 
• 868-85-9 Dimethyl phosphite 

Relevant academic research and scientific papers

Rapid TiO2/SBA-15 synthesis from ilmenite and use in photocatalytic degradation of dimethoate under simulated solar light

SBA-15 mesoporous materials loaded with 8%–42% TiO2 were prepared by post-synthesis hydrolysis using ilmenite as the TiO2 source. X-ray diffraction, high-resolution transmission electron microscopy, nitrogen adsorption–desorption measurements, and Fourier-transform infrared, X-ray photoelectron, Raman, and ultraviolet-visible spectroscopies were used to investigate the TiO2/SBA-15 morphology and crystal structure. The results show that TiO2 was successfully loaded on the mesoporous SBA-15 and the highly ordered two-dimensional hexagonal structure was stable. The photocatalytic performances of the samples in dimethoate degradation under simulated solar light were investigated. The photocatalytic activity initially increased and then decreased with increasing TiO2 loading. The 26% TiO2/SBA-15 sample showed the highest photocatalytic activity and completely degraded dimethoate within 7 h. The catalytic activity of TiO2/SBA-15 was 62% higher than that of pure TiO2. This may be because of a synergistic effect resulting from the adsorption of dimethoate on the mesoporous material. The presence of Ti–O–Si species enhances the TiO2 surface acidity and formation of surface adsorption sites; The adsorption and electron delocalization properties of SBA-15 are the main reasons for the observed enhancement of the pesticide degradation rate. These improves the TiO2/SBA-15 photocatalytic activity. TiO2/SBA-15 maintained high photocatalytic activity and good stability during four cycles, with a dimethoate degradation rate greater than 94%. The byproducts generated during photocatalysis were identified using gas chromatography-mass spectrometry. The photocatalytic degradation of dimethoate followed first-order kinetics. The mechanism of the photocatalytic degradation of dimethoate was investigated.

Method for preparing O, O-dimethyl-S-methylcarbamoylmethyl phosphorodithioate

The invention belongs to the technical field of pesticides, and particularly relates to a method for preparing O, O-dimethyl-S-methylcarbamoylmethyl phosphorodithioate. Chloroacetyl chloride and dimethyl phosphite are used as raw materials to prepare the O, O-dimethyl-S-methylcarbamoylmethyl phosphorodithioate for the first time, the product prepared by using the method is high in yield and purity, no waste liquid is generated in the preparation process, the preparation process is simple, and reaction mother liquor, such as the mother liquor in the step 1 and the step 3, does not need to be treated and can be recycled 6-8 times; while the yield of the product is further improved, the product keeps a high purity, and the quality of the product is ensured. By using the method, through optimization of a reaction system and selection of reaction details, the yield in the reaction in each step can be high. Besides, by using the method, after the reaction is completed, through simple aftertreatment steps, the water content of the obtained product can be as low as 0.032%, and the problem is solved that the product is decomposed due to high water content.

An improved process for synthesizing pie (by machine translation)

The invention discloses a method for synthesizing pie of the improved process, the method is in the use of the latter amine solution in the process of preparing pie, the prepared pie crude crude oil first dried, then exsolution, prepared crude oil pie. The invention through a plurality of technological improvement, to the maximum extent and improved reaction environment, improves the main reaction process, reduce hydrolysis, of improving the reaction yield, and containing salt compound after treatment is more convenient. The use of the technique of the invention, oxygen can be improved to phosphorus [...] yield 86% or more, and also to increase the purity of 90% or more; and ammonium chloride purity can be up to 99% or more, can be directly used as by-product first class sales, pie can be improved to the total crude yield 79% above; the purity of the crude oil is also improved, greatly improve the overall process, social, economic benefit is enormous. (by machine translation)

A thiophosphate synthetic method of compound and the method in a plurality of pharmaceutical application in the synthesis of (by machine translation)

The invention discloses a having the general formula (III) of the thiophosphate synthetic method of compound, the purpose is to provide a novel, condition is simple, easy to industrial production of the thiophosphate synthetic method of compound. The method is to have the general formula (I) of the organophosphorus oxygen apperception compound having the general formula (II) with a mercaptan or phenyl-sulfhydryl apperception compound mixed, under the effects of catalyst, obtained by the reaction of the formula (III) of the thiophosphate compound. The method of the invention, can be cheap efficient synthesis of thiophosphate compounds, in actual production will have extensive application prospect. (by machine translation)

A new method for the determination of some organophosphate insecticides

A quick and convenient method has been developed for milligram determination of some organophosphate insecticides. The sample is allowed to react with a calculated excess of (0.1 N) chloramine-T reagent in the presence of glacial acetic acid for 10-15 min at room temperature. After the reaction is over, KI solution (10%) is added and the unreacted reagent is back-titrated with 1 N solution of sodium thiosulfate to starch end-point. The method is applied for the determination of technical preparations of malathion (95%), dimethoate (90%), ethion (95%) and phorate (97%). The results are within the error of ±1.0%.

Condensation products

Formamidine compounds of the formula EQU1 or WHEREIN R1 represents a substituted or unsubstituted phenyl radical, R2 represents hydroogen, alkyl, alkenyl or alkinyl and R3 represents acyl their manufacture and their use in pest control.