反应详情

To a solution of methyl (R)-7-(4-fluorophenyl)-7-(2-hydroxy-3,4,6-trimethylphenyl)heptanoate (0.8 g, 2.1 mmol) and dichloromethyl methyl ether (0.62 ml) in dichloromethane (10 ml) was added dropwise a solution of titanium tetrachloride (0.76 ml) in dichloromethane (3 ml) under argon atmosphere while maintaining the temperatures of the reaction mixture at a range from -10 ° C. to -12° C. The reaction mixture was then stirred for 30 minutes at the same temperature range. The reaction mixture was then added to ice-water, which was subjected to extraction with ethyl acetate. The organic layer was washed with water, an aqueous solution of sodium hydrogencarbonate, water and a saturated aqueous saline solution, successively, followed by drying over magnesium sulfate. The solvent was distilled off under reduced pressure. The residue was recrystallized from chloroform/hexane to afford 0.63 g of methyl (R)-7-(4-fluorophenyl)-7-(3-formyl-6-hydroxy-2,4,5-trimethylphenyl)heptanoate. Physico-chemical properties and spectral data of the product were shown in [Table 4].

1. temperaturewhile maintaining the temperatures of the reaction mixture at a range from -10 ° C. to -12° C
2. extractionwas subjected to extraction with ethyl acetate
3. washThe organic layer was washed with water
4. dry with materialby drying over magnesium sulfate
5. distillationThe solvent was distilled off under reduced pressure
6. customThe residue was recrystallized from chloroform/hexane