Reaktion #348133

Reaktionsgleichung

4-chloro-3-(2,4-difluoro-5-nitrophenyl)-1-methyl-5-(trifluoro-methyl)-1H-pyrazole

butyl glycolate

NaH

→

(4-(4-chloro-1-methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl)-5-fluoro-2-nitrophenoxy)acetic acid, butyl ester

Ausbeute 72.0%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added in portions
2. 2
   workup.ADDITIONOnce the addition
3. 3
   SonstigeAfter 3 hours the mixture was carefully quenched with water
4. 4
   Extraktionextracted with ethyl acetate
5. 5
   WaschenThe ethyl acetate extracts were washed with brine
6. 6
   Trocknendried over anhydrous MgSO4
7. 7
   Einengenconcentrated in vacuo
8. 8
   SonstigeThe residue was purified chromatographically with 20% ethyl acetate/hexanes

Vorschrift

A solution of 3.4 g (0.01 mole) 4-chloro-3-(2,4-difluoro-5-nitrophenyl)-1-methyl-5-(trifluoro-methyl)-1H-pyrazole and 1.4 mL (0.011 mole) butyl glycolate in 25 mL anhydrous THF was chilled to 0° C. Maintaining the temperature below 5° C., 0.33 g (0.011 mole) NaH was added in portions. Once the addition was completed, the reaction mixture was allowed to warm to 25° C. After 3 hours the mixture was carefully quenched with water and extracted with ethyl acetate. The ethyl acetate extracts were washed with brine, dried over anhydrous MgSO4, and concentrated in vacuo. The residue was purified chromatographically with 20% ethyl acetate/hexanes to yield 3.25 g (72%) (4-(4-chloro-1-methyl-5-(trifluoromethyl)-1H-pyrazol-3-yl)-5-fluoro-2-nitrophenoxy)acetic acid, butyl ester as a light yellow solid; mp 65° C.

Quelle