反应详情

0.3 g of tert-butyl 5-(3-ethoxy-2-isopropoxy-3-oxo-1-propenyl)-2-methoxybenzoate was dissolved in 2.5 ml dichloromethane, and 1.2 ml trifluoroacetic acid was added under ice-cooling, and the mixture was stirred as such under ice-cooling for 2 hours. 30 ml toluene was added to the reaction mixture and the solvent was evapoarated; this procedure was repeated twice. Then, the residue was subjected to silica gel column chromatography, and from fractions eluted with hexane-ethyl acetate (2:1), 65 mg of 5-[(Z)-3-ethoxy-2-isopropoxy-3-oxo-1-propenyl]-2-methoxybenzoic acid was obtained.

1. temperaturecooling
2. temperaturecooling for 2 hours
3. washfrom fractions eluted with hexane-ethyl acetate (2:1)