Reaktion #937108

Reaktionsgleichung

3-(4-chloro-2-fluoro-5-methoxyphenyl)-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine

compound 1-1008

3-(4-chloro-2-fluoro-5-methoxyphenyl)-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine

potassium carbonate

methyl iodide

water

→

3-(4-chloro-2-fluoro-5-methoxyphenyl)-1-methyl-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine

Ausbeute 55.0%

Lösungsmittel

N,N-dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added
2. 2
   SonstigeAfter completion of the reaction
3. 3
   Extraktionfollowed by extraction with ethyl acetate
4. 4
   WaschenThe organic layer was washed with saturated sodium chloride solution
5. 5
   Trocknendried with anhydrous magnesium sulfate
6. 6
   Einengenconcentrated

Vorschrift

First, 3.61 g of 3-(4-chloro-2-fluoro-5-methoxyphenyl)-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine (compound 1-1008) was dissolved in 16 ml of N,N-dimethylformamide, to which 2.35 g of potassium carbonate and 1.39 ml of methyl iodide were added, and the mixture was stirred at 100° C. for 2 days. After completion of the reaction, the reaction mixture was poured into water, followed by extraction with ethyl acetate. The organic layer was washed with saturated sodium chloride solution, dried with anhydrous magnesium sulfate, and concentrated. The residue was subjected to silica gel column chromatography (eluent, hexane/ethyl acetate=5:1), which afforded 2.04 g (yield, 55%) of 3-(4-chloro-2-fluoro-5-methoxyphenyl)-1-methyl-6-trifluoromethyl-2-oxo-1,2-dihydropyrazine (present compound 1-144; m.p., 108.7° C.).

Quelle