Hydrochloric Acid → HCID 178516201, compound

Temperature

70 °C

A mixture of 25.0 g (266 mmol) of phenol and 30.0 g of cyclohexanol was charged, and 25.5 g (266 mmol) of sodium t-butoxide was added to the mixture over one hour, and then stirred at 70° C. for 30 minutes. The resultant solution was cooled to 40° C., and then 8.94 g (purity: 98%; 153.1 mmol) of 4-hydroxy-3,6-dichloropyridazine was added to the cooled solution. Then, the resultant mixture was heated from 40° C. to 140° C. to effect a reaction for 12 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, and 100 g of pure water and 100 g of toluene were added to the cooled mixture, and stirred for 30 minutes. Then, 41.7 g (400 mmol) of a 35% aqueous hydrochloric acid solution was added dropwise to the resultant mixture, and an organic phase containing phenol added in an excess amount was separated. 287 g of toluene was added to the resultant aqueous phase, and stirred at room temperature for 30 minutes, and then an organic phase was separated. Then, the resultant aqueous phase containing a sodium salt of 6-chloro-3-phenoxy-4-pyridazinol was added dropwise to a 35% aqueous hydrochloric acid solution at 0° C. to deposit solids, followed by filtration. The resultant solids were washed with pure water and dried under a reduced pressure, and dissolved in an organic solvent and quantitatively determined by an HPLC area percentage method, which showed that 9.94 g of 6-chloro-3-phenoxy-4-pyridazinol (yield: 84.0%) was obtained.

1. additionwas charged
2. customa reaction for 12 hours
3. customAfter completion of the reaction
4. temperaturethe reaction mixture was cooled to room temperature
5. stirringstirred for 30 minutes
6. additionadded in an excess amount
7. customwas separated
8. addition287 g of toluene was added to the resultant aqueous phase
9. stirringstirred at room temperature for 30 minutes
10. customan organic phase was separated
11. additionThen, the resultant aqueous phase containing a sodium salt of 6-chloro-3-phenoxy-4-pyridazinol
12. additionwas added dropwise to a 35% aqueous hydrochloric acid solution at 0° C.
13. filtrationfollowed by filtration
14. washThe resultant solids were washed with pure water
15. customdried under a reduced pressure
16. dissolutiondissolved in an organic solvent

ORD record

ord-641a7ee4be2340938465cd4adcf6ed38

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08552182B2