反应详情

Diazomethane (2.8 g) in ether (100 ml) is added to ethyl 4-[4-(4-trifluoromethylphenoxy)phenoxy]-3-hydroxypentanoate (1.88 g, 3.75 mmol) in ether (5 ml) under N2 and in an ice bath. Small amounts of chromatographic silica gel are added to the mixture in the ice bath until the color disappears. The mixture is then stirred overnight with cooling. The silica gel is removed by filtration and the organic phase is dried and concentrated. The crude product is purified by preparative thin layer chromatography to yield ethyl 4-[4-(4-trifluoromethylphenoxy)phenoxy]-3-methoxypentanoate (cpd. 1 in Table A). MS m/e 412 (m+).

1. temperaturewith cooling
2. customThe silica gel is removed by filtration
3. customthe organic phase is dried
4. concentrationconcentrated
5. customThe crude product is purified by preparative thin layer chromatography