A kind of process method of purifying pyraclostrobin by vapor deposition method

Abstract

A method for purifying pyraclostrobin by vapor deposition includes steps: (1) respectively extracting crude pyraclostrobin with ammonium hydroxide and deionized water, performing vacuum distillation and desolvation, filtering, washing and drying to obtain a yellow oily substance; (2) transferring the yellow oily substance obtained at the step 1 into a glass tube, and sealing an opening of the glass tube by oxy-acetylene flame under protection of nitrogen; (3) heating the sealed glass tube in a drying oven for 1h at 230 DEG C to gasify the yellow organic substance; (4) taking out the glass tube, cooling to the room temperature, and collecting white solid; (5) dissolving the white solid obtained at the step 4, filtering, and performing vacuum rectification. According to the method for purifying pyraclostrobin by vapor deposition, high-boiling-point substances can be separated effectively, and a pyraclostrobin mixture obtained by separation is subjected to vacuum rectification to obtain pyraclostrobin with purity higher than 95%. The method is simple in operation and low in cost, and impurity separation can be well realized to achieve purification.

Description

technical field [0001] The invention relates to the purification of the product pyraclostrobin, in particular to a process for purifying pyraclostrobin by vapor deposition. Background technique [0002] Pyraclostrobin is a methoxyacrylate fungicide with a pyrazole structure. It was discovered by BASF in 1993, registered and launched in 2001, and has been used on more than 100 crops. In 2009, its sales reached 735 million US dollars, second only to azoxystrobin, becoming the second largest fungicide in the world. Pyraclostrobin has broad spectrum, high efficiency, low toxicity, is safe to non-target organisms, and is safe and friendly to users and the environment. It is an important product with good market prospects among strobilurin fungicides and whose patent is about to expire. [0003] Because pyraclostrobin uses a lot of organic solvents, various acids, alkalis and other substances in the preparation process, the yield and purity of the product pyraclostrobin are great...

AI Technical Summary

Problems solved by technology

[0003] Because pyraclostrobin uses a lot of organic solvents, various acids, alkalis and other substances in the preparation process, the yield and purity of the product pyraclostrobin are greatly affected

Existing purification methods mainly adopt methods such as rectification, extraction, and filtration. These methods are simple in process and low in cost, but cannot improve the yield and purity of pyraclostrobin, resulting in waste of raw materials