Dimethoates

The oxidation of terminal alkenes with an EWG in alcohols or ethylene glycol affords acetals of aldehydes chemoselectively. Acrylonitrile is converted into l,3-dioxolan-2-ylacetonitrile (69) in ethylene glycol and to 3,3-dimetho.xy-propionitrile (70) in methanol[28j. 3,3-Dimethoxypropionitrile (70) is produced commercially in MeOH from acrylonitrile by use of methyl nitrite (71) as a unique leoxidant of Pd(0). Methyl nitrite (71) is regenerated by the oxidation of NO with oxygen in MeOH. Methyl nitrite is a gas, which can be separated easily from water formed in the oxidation[3]. 

Organophosphorus compounds (malathion, dimethoate, phorate, and parathion methyl)... 

Fig. 1 Absorption scan of a chromatogram track with 150 ng of each substance per chromatogram zone 1 = demeton-S-methylsulfone, 2 = dimethoate, 3a = transmevinphos,...

Diethyl aniline, 54 Diethylcarbaniazine citrate, 54 Diethyl carbamyl chloride, 54 Diethyl chlorophosphate, 54 Diethylene triamine, 54 Diethyl ether, 54 Di(2-ethylhexyl) phthalate, 54 Diethyl ketone, 54 Diethyl-p-phenylenediamine, 54 Diethyl phthalate, 54 Diethylstilbestrol, 55 Diethyl sulfate, 55 Diethyl zinc, 55 Difluoromethane chloride, 55 Digitoxin, 55 Diglycidyl ether, 55 Digoxin, 55 Diisobutyl ketone, 55 Diisopropylamine, 55 Diisopropyl ether, 55 DIKAMIN , 2,4-D, 55 DIKONIRT , 2,4-D, 55 Dimefox, 55 Dimethoate, 55 3,3 -Dimethoxybenzidine, 55 n,n-Dimethylacetamide, 56 Dimethylamine, 56 4-Dimethylaminoazobenzene, 56 Dimethylaminoethanol, 56 n,n-Dimethyl aniline, 56 7,12-Dimethylbenz[a]anthracene, 56 3,3 -Dimethylbenzidine, 56... 

NPIRS - National Pesticide hiformation Retrieval System, 306 NufamiLtd., 142, 196 NUGOR , dimethoate, 100... 

Figure 13.19 Chromatograms obtained by on-line SPE-GC-MS(SIM) of (a) 10 ml of tap water spiked with pesticides at levels of 0.1 ng 1 (b) 10 ml of a sample of unspiked tap water. Peak identification foi (a) is as follows 1, molinate 2, a-HCH 3, dimethoate 4, simazine 5, ati azine 6, y-HCH 7, S-HCH 8, heptachloi 9, ametiyn 10, prometiyn 11, fen-itrothion 12, aldrin 13, malatliion 14, endo-heptachlor 15, a-endosulfan 16, teti achlor-vinphos 17, dieldrin. Reprinted from Journal of Chromatography, A 818, E. Pocumll et al., On-line coupling of solid-phase exti action to gas cliromatography with mass specti ometiic detection to determine pesticides in water , pp. 85-93, copyright 1998, with permission from Elsevier Science.

SS,lS)-l-[2,5-his(lerl-butyldimethylsilyloxy)-3,4,6-trimethylphenyl -3-methyl-4,4-dimetho.xy-2-(4-methylphenylsulfmyf)-3-buteno yield 78%... 

Dichlorovos, phorate, dimethoate, diazinon, disulfoton, methyl-parathion, malathion, parathion, azinphos-methyl, azinphos-ethyl, and so on... 

Isoquinoline, 3,4-dihydro-6,7-dimetho y-1-methyl-[4721-98-6], 4 ISOQUINOLINE, 1-(FHENYLMETHYL)-[6907-59-1], 19... 

The reagent sequence is specific for endosulfan and phosphamidon. Other insecticides, e.g. organochlorine insecticides, such as endrin, aldrin, dieldrin, DDT and BHC, organophosphorus insecticides, such as malathion, parathion, dimethoate, quinalphos, phorate and fenitrothion, or carbamate insecticides, such as baygon, car-baryl and carbofuran do not react. Neither is there interference from amino acids, peptides or proteins which might be extracted from the biological material together with the pesticides. 

Demeton-S-methyl sulfone (hRf 0-5), dimethoate (h/ f 5-10), demeton-S-metlq (hRf 20-25), triazophos (h/ f 40-45), azinphos-methyl (hRf 40-45), azinphos-ethj (hRf 50-55), malathion (h/ f 60-65), parathion-methyl (hRf 75-80) and parathioo ethyl (h/ f 80-85) yielded yellow to brown chromatogram zones on a light brown bact ground, with thiophosphate insecticides with P = S double bonds appearing as brow zones and those with single P — S bonds as yellow zones. 

In situ quantitation The absorption photometric quantitation was carried out in M flectance at a mean wavelength of A, = 370 nm. The detection limits per chromatogran zone lay between 10 ng for dimethoate and 20 ng for parathion-ethyl. 

Gomez-Arroyo S, Noriega-Aldana N, Juarez-Rodriguez D, et al. 1987. Sister chromatid exchanges induced by the organophosphorus insecticides methyl parathion, dimethoate, phoxim and methyl azinphos in cultured human lymphocytes. Contaminacion Ambiental 3 63-70. 

Institoris L, Siroki O, Desi I. 1995. Immunotoxicity study of repeated small doses of dimethoate and methyl parathion administered to rats over three generations. Hum Exp Toxicol 14 879-883. 

El Beit lOD, Wheelock JV, Cotton DE. 1981a. Factors affecting soil residues of dieldrin, endosulfan, gamma-HCH, dimethoate, andPyrolan. Ecotoxicol Environ Safety 5 135-160. 

Ozmen G, Elcuman A. 1998. [Combined effects of endosulfan dimethoate and carbaryl on serum calcium levels and heart muscle of rats] Turk J Biol 22 317-322. (Turkish)... 

Usha Rani MV, Reddi OS, Reddy PP. 1980. Mutagenicity studies involving aldrin, endosulfan, dimethoate, phosphamidon, carbaryl and ceresan. Bull Environ Contam Toxicol 25 277-282. 

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