Reaction #2545
ord-b9a7125374424a33a8c178a8e25b8efd
Reaction equation
Reactants
Reagents
Conditions
Workup
- 1Temperatureheated
- 2Temperatureunder reflux for 4 hours
- 3ConcentrationAfter concentrating the reaction solution to 1/3 volume, insoluble materials
- 4Otherwere removed by filtration
- 5TemperatureTo the resulting filtrate cooled in an ice bath
- 6OtherThe resulting reaction mixture
- 7Extractionextracted with methylene chloride
- 8Washwashed with 10% citric acid aqueous solution, water and saturated brine in that order
- 9DryingAfter drying on anhydrous magnesium sulfate
- 10Otherremoving the solvent
- 11Otherby evaporation
- 12Otherto obtain creamy-colored powder
- 13workup.ADDITIONTo this were added
- 14Temperatureof heating
- 15Temperatureunder reflux
- 16Filtrationfiltering off the formed insoluble materials
- 17Otherthe organic solvent was removed by evaporation
- 18ExtractionThe resulting residue was extracted with ethyl acetate
- 19Washthe organic layer was washed with saturated brine
- 20Dryingdried on anhydrous magnesium sulfate
- 21Otherfollowed by the removal of the solvent by evaporation
- 22Otherto obtain an orange oily material
- 23workup.STIRRINGAfter 1 hour of stirring at the same temperature
- 24Temperaturewarmed to room temperature
- 25OtherAfter removing methanol
- 26Otherby evaporation, ethyl acetate extraction
- 27Washthe resulting organic layer was washed with saturated brine
- 28Dryingdried on anhydrous magnesium sulfate
- 29Othersubjected to evaporation
- 30Otherto remove the solvent
- 31Washthe resulting colorless solid material was washed with an ether-hexane (2:1) mixture solution
Procedure
N-Bromosuccinimide (1.29 g, 7.2 mmol) and AIBN (50 mg, 0.30 mmol) were suspended in carbon tetrachloride (80 ml), mixed with m-toluyl chloride (0.8 ml, 6.0 mmol) and then heated under reflux for 4 hours while exposing to light. After concentrating the reaction solution to 1/3 volume, insoluble materials were removed by filtration. To the resulting filtrate cooled in an ice bath were added dropwise o-anisidine (0.69 ml, 6 mmol) and 20% sodium hydroxide aqueous solution (5 ml) in that order. The resulting reaction mixture was stirred for 20 minutes at room temperature, extracted with methylene chloride and then washed with 10% citric acid aqueous solution, water and saturated brine in that order. After drying on anhydrous magnesium sulfate and removing the solvent by evaporation, the resulting light beige solid material was subjected to silica gel column chromatography (ether:hexane=1:1) to obtain creamy-colored powder. To this were added precipitated calcium carbonate (2.34 g, 23.4 mmol) and a dioxane-water (1:1) mixture solution (20 ml), followed by 6 hours of heating under reflux. After adding THF (50 ml) and filtering off the formed insoluble materials, the organic solvent was removed by evaporation. The resulting residue was extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried on anhydrous magnesium sulfate, followed by the removal of the solvent by evaporation to obtain an orange oily material. This was dissolved in methanol (15 ml), and sodium borohydride (90 mg, 2.34 mmol) was added to the solution in one portion at -15° C. After 1 hour of stirring at the same temperature, the reaction mixture was mixed with acetone (1 ml), warmed to room temperature and then mixed with saturated ammonium chloride aqueous solution (10 ml). After removing methanol by evaporation, ethyl acetate extraction was carried out, and the resulting organic layer was washed with saturated brine, dried on anhydrous magnesium sulfate and then subjected to evaporation to remove the solvent. The thus obtained residue was subjected to silica gel column chromatography (ether:hexane=3:1), and the resulting colorless solid material was washed with an ether-hexane (2:1) mixture solution to obtain 1.02 g (66.1%) of the title compound in the form of colorless powder.