Hydrochloric Acid → 4-Hydroxy-6-(4-trifluoromethylphenylthio)2-hexanone

19.72 Grams of methyl acetoacetate were dissolved in 30 ml of water, and 25.33 g of a 30% aqueous sodium hydroxide solution were added thereto by drops while cooling the mixture to 25° C. or less. After having been stirred at 30°-35° C. for 3 hours, the mixture was adjusted to pH 7.0 with a concentrated aqueous hydrochloric acid solution. Thereafter, 0.98 g of sodium acetate and then an additional concentrated aqueous hydrochloric acid solution were added to the mixture so that the mixture had a pH of 6.9. And 40 ml of methanol and then 23.44 g of 3-(4-trifluoromethylphenylthio)propanal were added thereto. The resulting mixture was stirred at 45°-50° C. for 10 hours. The mixture was concentrated under reduced pressure, and the residue obtained was extracted three times with ethyl acetate. The organic layers were combined, washed twice with a 5% aqueous acetic acid solution and then twice with a saturated aqueous sodium chloride solution and thereafter dried over anhydrous magnesium sulfate. Removing the solvent from the washed layer under reduced pressure gave 22.64 g of crude 4-hydroxy-6-(4-trifluoromethylphenylthio)-2-hexanone (purity: 89.6%, yield: 69.4%).

1. temperatureby drops while cooling the mixture to 25° C. or less
2. stirringThe resulting mixture was stirred at 45°-50° C. for 10 hours
3. concentrationThe mixture was concentrated under reduced pressure
4. customthe residue obtained
5. extractionwas extracted three times with ethyl acetate
6. washwashed twice with a 5% aqueous acetic acid solution
7. dry with materialtwice with a saturated aqueous sodium chloride solution and thereafter dried over anhydrous magnesium sulfate
8. customRemoving the solvent from the washed layer under reduced pressure

ORD record

ord-6b2696cce5e246b0966ec52619b883e5

Source dataset

uspto-grants-1992_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05101076