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Organophosphate insecticides for its superior insecticidal activity , low prices become the backbone of pesticides . In China the production of forty several organophosphorus insecticides less toxic varieties , mostly highly toxic pesticides . 2004 China has stopped production and use of five highly toxic pesticides. Therefore, the development of low toxicity, high broad-spectrum organophosphate insecticide become China's pesticide research priority. Diazinon 1950s developed organophosphate insecticide , has become one of the main varieties of pesticides . United States, Japan , Britain, Switzerland, has a production, its production are in tons . It is a broad-spectrum organophosphate insecticide with contact and stomach poison , fumigation and a certain role within the gully , its application range covers almost all the major crops. Domestic diazinon had a preliminary study , and even some manufacturers during production, but mainly in the form of processing , product purity can only guarantee about 90% , the yield is low. According to the survey , the domestic intermediate pyrimidine alcohol synthesis method using methanol , synthetic diazinon uses aromatic hydrocarbons or hydrocarbon solvents , long production cycle , product darker color , high energy consumption , low purity . Thesis isobutyronitrile based synthesis intermediate 2 - isopropyl-4 - methyl-6 - hydroxy- pyrimidine change dependent on foreign imports of production situation. Intermediates ancymidol using methanol synthesis , after imidization , amidination cyclization synthesis of three steps , through experiments , the method to solve the problem of caking , compared with the original drug synthesis using foreign advanced ketone solvent , high yield, high purity, low cost, total yield in the original drug isobutyronitrile total of 85%, purity ≥ 95%, estimate the cost of raw materials is only 27,000 yuan / ton , in the country in the advanced level . The process method also has simple operation, suitable for industrialization. This paper also intermediate with the original drug diazinon analysis method of the study, in which the imine -butyl ester hydrochloride , monitored by gas chromatography , isobutyl amidine hydrochloride was analyzed using the chemical method ; 2 - isopropyl-4 - methyl-6 - hydroxy- pyrimidine by chemical analysis ; original drug analysis by gas chromatography . These methods solve the production process quality problems.
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