Method for preparing 5-chloro-8-hydroxyquinoline
A technology of hydroxyquinoline and chloro-o-quinoline, applied in the field of preparing 5-chloro-8-hydroxyquinoline, can solve the problems of cumbersome loss, low yield, incomplete reaction, etc., achieve cost reduction, high content, and increase the total Yield effect
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Publication Date
- 2012-08-08
- Estimated Expiration
- Not applicable · inactive patent
Abstract
Description
technical field
[0001] The invention relates to the technical field of chemical industry, in particular to a method for preparing 5-chloro-8-hydroxyquinoline. Background technique
[0002] 5-Chloro-8-hydroxyquinoline is mainly used in the synthesis of herbicide component Jieduquine, and is also used as an animal food additive, disinfectant and metal preservative. There are many ways to prepare 5-chloro-8-hydroxyquinoline. The synthetic technical literature of the 5-chloro-8-hydroxyquinoline that is seen in report and disclosure mainly contains: 1., use 8-hydroxyquinoline as raw material, be a solvent with a large amount of glacial acetic acid, prepare 5-chloro-8-hydroxyquinoline with chlorine gas Hydroxyquinoline, the yield is 52.7% (JP162066), the main by-product is 5,7-dichloro-8-hydroxyquinoline. The shortcoming of this technology is that main raw material is expensive, and reaction selectivity is poor, and impurity is many; 2., be raw material with 8-hydroxyquinoline, p...
Examples
Embodiment 1
[0010] In a 1000L reactor, put 100 kg of 4-chloro-o-nitrophenol, 173.7 kg of 4-chloro-o-aminophenol, and 175 kg of glycerin, stir and heat up to 120°C, add 410 kg of sulfuric acid dropwise, and finish the dropwise reaction at 150°C for 3 Hour. During the heat preservation period, 70 kg of water was removed by vacuum. After the heat preservation reaction, the temperature was lowered to 60° C., and 10% aqueous sodium hydroxide solution was added dropwise until the pH value was 7. Centrifuge, put the filter cake into a 3000L kettle, add 2200 kg of water, 200 kg of 32% industrial hydrochloric acid, 15 kg of activated carbon, and filter after dissolving. The filtrate is pumped into another 3000L kettle, and 233 kg of 30% liquid caustic soda is added dropwise to neutralize and centrifuge. Filter cake is put into another 2000L kettle, adds 1250 kilograms of 32% industrial hydrochloric acid, centrifuges after stirring for 1 hour.
[0011] Put the filter cake into another 3000L kett...
Embodiment 2
[0013] In a 1000L reactor, put 97 kg of 4-chloro-o-nitrophenol, 145 kg of 4-chloro-o-aminophenol, 150 kg of glycerin and 100 kg of toluene, stir and heat up to 105°C, add 410 kg of sulfuric acid dropwise, and drop it at 110 ℃-145 ℃ heat preservation reaction for 5 hours. During the heat preservation period, 65 kg of water was removed and toluene was evaporated. After the heat preservation reaction, the temperature was lowered to 60° C., and 10% aqueous sodium hydroxide solution was added dropwise until the pH value was 7. Centrifuge, put filter cake in 3000L kettle, add 1850 kg of water, 170 kg of 32% industrial hydrochloric acid, 12 kg of activated carbon, filter after dissolving. The filtrate is pumped into another 3000L kettle, and 200 kg of 30% liquid caustic soda is added dropwise for neutralization and centrifuged. Put the filter cake into another 2000L kettle, add 1100 kilograms of 32% industrial hydrochloric acid, and centrifuge after stirring for 1 hour. Put the fi...
Embodiment 3
[0015] In a 1000L reaction kettle, put 97 kg of 4-chloro-o-nitrophenol, 160 kg of 4-chloro-o-aminophenol, and 150 kg of glycerin, stir and heat up to 120°C, add 410 kg of sulfuric acid dropwise, and finish the dropwise reaction at 150°C. Hour. After the heat preservation reaction, the temperature was lowered to 60° C., and 10% aqueous sodium hydroxide solution was added dropwise until the pH value was 7. Centrifuge, put filter cake into 3000L kettle, add 2050 kg of water, 160 kg of 32% industrial hydrochloric acid, 20 kg of activated carbon, filter after dissolving. The filtrate is pumped into another 3000L kettle, and 187 kg of 30% liquid caustic soda is added dropwise to neutralize and centrifuge. Put the filter cake into another 2000L kettle, add 770 kg of ethanol, 330 kg of water and 15 kg of activated carbon, heat to dissolve, filter and decolorize, and cool the filtrate to 0 degrees for centrifugation. The filter cake was dissolved and decolorized once with 770 kg of e...
