Reaktion #348139

Reaktionsgleichung

BBr3

4-chloro-3-(2-fluoro-4-methoxy-5-nitrophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrazole

→

4-(4-chloro-1-methyl-5-(trifluoro-methyl)-1H-pyrazol-3-yl)-5-fluoro-2-nitrophenol

Ausbeute 54.0%

Lösungsmittel

methylene chloride

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   WaschenThe solution was washed two times with water
2. 2
   Trocknendried over anhydrous MgSO4
3. 3
   Einengenconcentrated in vacuo
4. 4
   SonstigeThe residue was recrystallized from hexane

Vorschrift

A solution of 1.4 g (4 mmole) 4-chloro-3-(2-fluoro-4-methoxy-5-nitrophenyl)-1-methyl-5-(trifluoromethyl)-1H-pyrazole in 20 mL methylene chloride was chilled to 0° C. Next 5.0 mL of a 1M methylene chloride solution of BBr3 (4.9 mmole) was added slowly over 10 minutes. The solution was allowed to stir overnight at room temperature. The solution was washed two times with water, dried over anhydrous MgSO4, and concentrated in vacuo. The residue was recrystallized from hexane to give 0.7 g (54%) of 4-(4-chloro-1-methyl-5-(trifluoro-methyl)-1H-pyrazol-3-yl)-5-fluoro-2-nitrophenol as a beige solid, mp 89°-90° C.

Quelle