Method for preparing 2,3-dichlorotoluene
A dichlorotoluene and o-tolyl-based technology, applied in 2 fields, can solve the problems of inaccessibility of raw materials, high price, long time-consuming and the like of the synthetic route, and achieve the effects of low cost, low price and environmental friendliness
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0028] Embodiment 1: Add o-toluidine 43ml, urea 18g, and xylene 170ml in the 500ml round-bottomed three-neck flask that stirring, measuring temperature and reflux device are housed and heat up to 138 ℃, reflux reaction 7 hours, pour out while hot. Then cool to normal temperature under stirring, filter, the filter cake is washed with xylene, drained, and dried, and then washed with a large amount of water, drained, and dried to obtain 42.90 g of white needle crystals, in terms of o-toluidine, N, The yield of N'-di(o-tolyl)urea was 89.40%.
[0029] Pour 67mL of sulfuric acid into a 500mL three-necked flask equipped with a thermometer and an exhaust gas recovery device, weigh 24.00g of N,N'-di(o-tolyl)urea, add it to the solution in batches under stirring, and the addition temperature does not exceed 50°C , after the N,N'-di(o-tolyl)urea was completely dissolved, the temperature was kept at 65° C. for 6 hours, and then the heating was stopped. This gives N,N'-di(o-tolyl)urea-4,4...
Embodiment 2
[0031] Embodiment 2: Weigh 24.00 N, N'-bis(o-tolyl)urea and put it into a 1000ml three-necked flask, pour 10% oleum of 62ml into the dropping funnel, add dropwise and the temperature does not exceed 50°C , dissolve N, N'-bis(o-tolyl)urea, wait until N,N'-bis(o-tolyl)urea is completely dissolved, keep the temperature at 65°C for 6 hours, stop heating. Get N,N'- Bis(o-tolyl)urea-4,4'-disulfonic acid. Add 300ml of water, 160ml of dilute hydrochloric acid and 0.56g of iron powder, pass chlorine gas, keep the heating temperature at 35°C, and react for 12h. To obtain N,N'-bis(2-chloro-6-methylphenyl)urea-4,4'-disulfonic acid, assemble a reflux device, pass nitrogen protection, slowly raise the temperature of the reaction solution to 107°C, and heat-preserve and hydrolyze for 3h Afterwards, the solution was heated to 175° C. in an autoclave. React for 10 hours. After cooling, use sodium carbonate to neutralize to neutrality, then carry out steam distillation, collect the distillat...
Embodiment 3
[0032] Embodiment 3: Weigh 24.00 N, N'-bis(o-tolyl)urea and put it into a 1000ml three-necked flask, pour 67ml of 98% concentrated sulfuric acid into the dropping funnel, add dropwise and the temperature does not exceed 50°C, Dissolve N,N'-di(o-tolyl)urea, wait until N,N'-bis(o-tolyl)urea is completely dissolved, keep the temperature at 65°C for 6 hours, stop heating. Obtain N,N'-di(o-tolyl)urea (o-tolyl)urea-4,4'-disulfonic acid. Add 300ml of water, 160ml of dilute hydrochloric acid and 0.56g of iron powder, pass chlorine gas, keep the heating temperature at 35°C, and react for 12h. To obtain N,N'-bis(2-chloro-6-methylphenyl)urea-4,4'-disulfonic acid, assemble a reflux device, pass nitrogen protection, slowly raise the temperature of the reaction solution to 107°C, and heat-preserve and hydrolyze for 3h Afterwards, the solution was heated to 175° C. in an autoclave. React for 10 hours. After cooling, use sodium carbonate to neutralize to neutrality, then carry out steam di...
PUM
Abstract
Description
Claims
Application Information
- R&D Engineer
- R&D Manager
- IP Professional
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.
© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com