反应详情

To a solution of 17.8 g (67.9 mmol) of triphenylphosphane, 8.8 ml (67.9 mmol) of 2-(2,4-dichlorophenyl)ethanol and 16 g (61.3 mmol) of 4-bromo-3,5-dihydroxybenzoic acid ethyl ester in 25 ml of THF was added a solution of 10.6 ml (67.9 mmol) of DEAD in 40 ml of THF within 45 min between 6° and 18° C. After 16 h at room temperature the solvent was removed and the residue was stirred with cyclohexane/ethyl acetate (1/1) and filtered. The solid residue was stirred with cyclohexane and filtered. The remaining solid was separated by chromatography (cyclohexane/ethyl acetate (1/1)) to give 25.6 g (96%) of the title compound.

1. customAfter 16 h at room temperature the solvent was removed
2. filtrationfiltered
3. stirringThe solid residue was stirred with cyclohexane
4. filtrationfiltered
5. customThe remaining solid was separated by chromatography (cyclohexane/ethyl acetate (1/1))