preparation of 2-mercaptopyridine-n-oxide_industrial additives

preparation background and overview of 2-mercaptopyridine-n-oxide

2-pyrithione-n-oxyfluoroborate can be used to prepare zinc pyrithione. add an appropriate amount of zinc oxide to the 2-pyrithione-n-oxide solution, react at 40-90°c for 3-6 hours, filter and wash with water , after drying, zinc pyrithione is obtained. zinc pyrithione is used in shampoos to remove dandruff and can inhibit the growth of gram-positive and gram-negative bacteria and mold. it can effectively care for hair, delay hair aging, and control the occurrence of gray hair and hair loss. in addition, it is also used as a cosmetic preservative, oil agent, and paint biocide. it can also be used as a preservative, antifouling agent, etc., and is widely used in agriculture, industry, medicine, health, cosmetics and other fields.

preparation of 2-mercaptopyridine-n-oxide

preparation report of 2-mercaptopyridine-n-oxide 1.

add 20g 2-chloropyridine and 0.6g catalyst tio₂ into a 500ml reaction bottle, raise the temperature to 50°c, and add 20g 30% hydrogen peroxide dropwise. the amount of hydrogen peroxide and 2-chlorine the material ratio of pyridine is 1:1, react for 10 hours, cool to room temperature, filter, drain the filter cake, and wash with 10g of deionized water. the filtrate is 2-chloropyridine nitrogen oxide aqueous solution; the system is heated to 70°c. add dropwise to the mixed solution of 30g 25% naoh solution and 21g 43% nahs solution, and keep warm for 6 hours. then cool to room temperature, adjust the ph value to 4.5, add 1g of activated carbon for decolorization for 0.5h, and obtain a 2-mercaptopyridine-n-oxide solution;

preparation report 2 of 2-mercaptopyridine-n-oxide,

step 1: oxidation reaction: add 2-chloropyridine, catalyst and deionized water to the reactor, raise the temperature to 60°c, stir for 2.5h, slowly add hydrogen peroxide dropwise, raise the temperature to 80°c, keep warm for 5h, and then add sodium hydroxide dropwise to adjust the ph to 8 to generate a 2-chloro-n-oxypyridine solution;

second benzylpyridine step: thiolation reaction: add sodium hydrogen sulfide solution and sodium hydroxide solution dropwise into the reaction kettle of the 2-chloro-n-oxypyridine solution in the first step to adjust the ph to 10, and adjust the ph to 90 stir for 3 hours at a temperature of ℃ to generate a 2-mercapto-n-oxypyridine solution.

references

[1]cn107628995-a synthesis method of zinc pyrithione

[2]cn105906560-a method for producing uniform plate crystal zinc pyrithione