Background and overview[1]
The chemical name of thiazothionate is: (RS)-S-sec-butyl-O-ethyl-2-oxo-1,3-thiazolidin-3-ylphosphonate, which is Rohm and Haas Resin is a broad-spectrum, low-toxic and highly effective insecticide and nematicide. Due to unsafe factors in the current production process and limited production capacity, the market has been in short supply in recent years. Japanese patent reports use metallic sodium as a base. A large amount of hydrogen is generated during this reaction, which poses a great safety hazard during production and is not suitable for large-scale industrial production.
Apply[2]
Thionate is a highly efficient broad-spectrum insecticide and nematicide developed by Japan’s Ishihara Industrial Company in 1986. This variety was registered and put on the market in Japan in 1992 and is widely used for pest control of vegetables, citrus, bananas, coffee, tobacco and ornamental plants.
Preparation[1-2]
A method for preparing thiazophosphorus, which is prepared by reacting 2-thiazolidinone and a base in a solvent to form a salt, and then performing a condensation reaction with O-ethyl-S-sec-butylphosphorothioate chloride. Obtained, the reaction formula is:
In a 2000ml three-necked flask equipped with an electric stirrer and a thermometer, add 800ml of toluene, 50g of 2-thiazolidinone, and 26g of sodium methoxide under stirring, stir at a temperature of 0 to 10 degrees for 10 hours, then cool to -80 degrees, and control Add dropwise a mixture of 100g of O-ethyl-S-sec-butylthiophosphoryl chloride and 100ml of toluene at a temperature of -80 to -60 degrees. After the dropwise addition, continue stirring for 5 hours. Then raise the temperature of the reaction solution to 0 degrees, and add 10% chlorine. Wash with 300 ml of sodium chloride aqueous solution × 3, dry the organic phase with anhydrous sodium sulfate, filter, and desolve under reduced pressure to obtain a light yellow oily liquid. Wash this light yellow oily liquid with 100 ml of petroleum ether × 2, and reduce the oily liquid in the lower layer after washing. Press and vacuum 1 anti-aging agent rdh at 50 degrees to obtain a light yellow oily liquid, i.e. thiazolidinone, with a net weight of 120g, a content of 95.0%, and a yield of 83.0% (calculated based on 2-thiazolidinone).
