Synthesis method of O, O-dialkyl thiphosphoryl chloride

Abstract

The invention discloses a synthesis method of O, O-diakyl thiphosphoryl chloride. In a reaction system where O, O-dialkyl S-hydro-phophorodithioate and chlorine are subjected to a chlorination reaction to prepare O, O-dialkyl thiphosphoryl chloride, an excess chlorine is introduced to make sulphur generated in the reaction be converted into disulfur dichloride, and disulfur dichloride is convertedinto sulfur dichloride afterwards; and by controlling the reaction temperature and arranging the reaction system to be in the negative pressure state, sulfur dichloride is moved out of the reaction system in the reaction process through distillation and condensing. The synthesis method substantially achieves the atomic economy based on a green chemistry concept; the overall cost of raw materialsis far lower than that in a traditional method, the amount of the three wastes is less, and the three wastes are easy to dispose; a traditional solid-liquid separation step is cancelled, automated production is facilitated, and meanwhile, improvement of the safety and environment production level of the device is facilitated; and O, O-dialkyl thiphosphoryl chloride is not in contact with water, disintegration of the product is avoided, the yield rate is as high as 93%, and the product content can reach 99%.

Description

technical field

[0001] The invention belongs to the technical field of preparation of pesticide intermediates, and in particular relates to a synthesis method of O, O-dialkylphosphoryl thiochloride. Background technique

[0002] O, O-dialkylphosphoryl thiochloride (referred to as alkyl monochloride, the same below) is a special intermediate for the synthesis of phosphorothioate pesticides, and is the most representative of O, O-dialkylphosphoryl thiochloride The most common ones are O, O-dimethylphosphoryl thiochloride (referred to as methyl monochloride, the same below) and O, O-diethylphosphoryl thiochloride (abbreviated as ethyl monochloride, the same below). Methyl monochloride and ethyl monochloride can be used to prepare nearly twenty kinds of high-efficiency, medium-low toxicity organophosphorus pesticides, such as acephate, pirimiphos-methyl, chlorpyrifos-methyl, fenitrothion, methyl-trimethoprim Cylphos, fenthion, pimofos, chlorpyrifos, chlorpyrifos, chlorpyrifos, ...

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