Sulfuric Acid → HCID 19818530, compound

Temperature

-78 °C

A solution of 3,4-dichloroacetophenone (5.0 g.)in tetrahydrofuran (50 ml.) was added dropwise to a stirred solution of lithium diisopropylamide (prepared from n-butyl-lithium [19.8 ml. of a 1.6 molar solution in hexane] and diisopropylamine (4.3 ml.) in tetrahydrofuran (200 ml.) during 10 minutes at 0° C.) which was cooled to -78° C., and the mixture was stirred at -78° C. for 30 minutes and then at -50° C. for 45 minutes, and then recooled to -78° C. Anhydrous hexafluoroacetone (10 ml., generated by treating the sesquihydrate with concentrated sulphuric acid) was distilled into the mixture, which was then stirred for 1 hour at -78° C. Methanol (10 ml.) and saturated aqueous ammonium chloride solution (50 ml.) were added, the mixture was allowed to warm up to laboratory temperature and was poured into water (250 ml.) and the mixture was extracted with diethyl ether. The extract was washed with saturated aqueous sodium chloride solution, dried over magnesium sulphate and evaporated to dryness under reduced pressure, and there was thus obtained as an oil 1-(3,4-dichlorophenyl)-4,4,4-trifluoro-3-hydroxy-3-trifluoromethylbutan-1-one which was used without further purification.

1. waitat -50° C. for 45 minutes
2. customrecooled to -78° C
3. distillationwas distilled into the mixture, which
4. stirringwas then stirred for 1 hour at -78° C
5. additionMethanol (10 ml.) and saturated aqueous ammonium chloride solution (50 ml.) were added
6. temperatureto warm up to laboratory temperature
7. additionwas poured into water (250 ml.)
8. extractionthe mixture was extracted with diethyl ether
9. washThe extract was washed with saturated aqueous sodium chloride solution
10. dry with materialdried over magnesium sulphate
11. customevaporated to dryness under reduced pressure, and there

ORD record

ord-55b7b1a662914b62bef26c6a1f938742

Source dataset

uspto-grants-1991_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05032592