反应详情

1.16 ml (16 mmol) Acetylchloride were added within 5 min to a ice cooled suspension of 2.4 g (16.4 mmol) AlCl3 in 5 ml 1,2-dichloroethane under an argon atmosphere. A solution of 1.13 g (8.2 mmol) 5-methoxy-2-methyl-phenol (PCT Int. Appl. WO 2003/084916 A2) in 2.4 ml 1,2-dichloroethane was added within 5 min. The mixture was naturally warmed to ambient temperature, poured after 4 h onto ice water and extracted twice with dichloromethane. The combined extracts were washed with ice water/0.5 M NaOH solution 1/1 and brine and dried over sodium sulfate. Removal of the solvent under reduced pressure gave a yellow oil which was dissolved in a mixture of 3.5 ml methanol, 7 ml THF and 7 ml 1 M LiOH solution. The solution was stirred for 30 min at ambient temperature and the solvent was partially removed under reduced pressure. Ice water/1 M HCl solution 1/1 was added and the solution was extracted twice with ethyl acetate. The combined extracts were washed with brine and dried over sodium sulfate. Evaporation of the solvent left a yellow solid which was crystallized from dichloromethane/methanol/heptane to yield 441 mg (2.45 mmol, 30%) of the title compound as colorless crystals.

1. temperaturecooled
2. additionpoured after 4 h onto ice water
3. extractionextracted twice with dichloromethane
4. washThe combined extracts were washed with ice water/0.5 M NaOH solution 1/1 and brine
5. dry with materialdried over sodium sulfate
6. customRemoval of the solvent under reduced pressure
7. customgave a yellow oil which
8. customthe solvent was partially removed under reduced pressure
9. additionIce water/1 M HCl solution 1/1 was added
10. extractionthe solution was extracted twice with ethyl acetate
11. washThe combined extracts were washed with brine
12. dry with materialdried over sodium sulfate
13. customEvaporation of the solvent
14. waitleft a yellow solid which
15. customwas crystallized from dichloromethane/methanol/heptane