반응 #653778

반응 방정식

chlorodifluoromethane

5-(4-chloro-2-fluoro-5-methylphenyl)-1,2-dihydro-2-methyl-3H-pyrazol-3-one

sodium hydroxide

→

3-(4-Chloro-2-fluoro-5-methylphenyl)-5-difluoromethoxy-1-methyl-1H-pyrazole

용매

water

dioxane

water

반응 조건

후처리

1. 1
   추출was extracted three times
2. 2
   건조The combined organic phases were dried over magnesium sulfate
3. 3
   여과filtered
4. 4
   농축concentrated
5. 5
   기타The residue was purified by means of column chromatography on silica gel (eluent: cyclohexane/ethyl acetate=9:1)

실험 절차

Gaseous chlorodifluoromethane was passed for 2 hours into a solution of 133 g (0.55 mol) of 5-(4-chloro-2-fluoro-5-methylphenyl)-1,2-dihydro-2-methyl-3H-pyrazol-3-one and 110 g (2.7 mol) of sodium hydroxide in 1 l of dioxane and 0.5 l of water at room temperature. The reaction solution was then poured into 2 l of water, whereupon the aqueous phase was extracted three times using ethyl acetate. The combined organic phases were dried over magnesium sulfate and then filtered and concentrated. The residue was purified by means of column chromatography on silica gel (eluent: cyclohexane/ethyl acetate=9:1) followed by preparative MPLC on silica gel (identical eluent). Yield: 43 g.

출처