Reaktion #9739

Reaktionsgleichung

sodium hydrogen sulfite

sodium bromate

methyl 2-methyl-5-[4-(trifluoromethyl)phenyl]-3-furoate

intermediate 23

methyl 2-methyl-5-[4-(trifluoromethyl)phenyl]-3-furoate

diethylether

→

title compound

methyl 2-(bromomethyl)-5-[4-(trifluoromethyl)phenyl]-3-furoate

Lösungsmittel

—

ice water

water

water

cyclohexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Waschenwashed with fresh water
2. 2
   WaschenThe organic layer was washed with 10% sodium thiosulfite solution
3. 3
   Trocknendried over magnesium sulfate
4. 4
   SonstigeThe crude product isolated by evaporation
5. 5
   Sonstigepurified by flash column chromatography

Vorschrift

A solution of sodium bromate (8.14 g) in water (27 ml) was treated with a suspension of methyl 2-methyl-5-[4-(trifluoromethyl)phenyl]-3-furoate (intermediate 23, 5.12 g) in cyclohexane (36 ml). The system was cooled to <10° C. in ice/water bath and treated with a solution of sodium hydrogen sulfite (9.4 g) in water (54 ml) in a drop-wise manner over 30 minutes. The reaction was allowed to warm up to 10° C. for 2 hours and then poured into diethylether (400 ml) and washed with fresh water. The organic layer was washed with 10% sodium thiosulfite solution and dried over magnesium sulfate. The crude product isolated by evaporation, was pre-adsorbed onto silica and purified by flash column chromatography using 39:1 cyclohexane:ethyl acetate as eluent to give the title compound as a white powder.

Quelle