反应详情

2-Allyl-4-benzyloxy-phenol (WO 9728137 A1 19970807, Adams et al.) (6.04 g, 25.1 mmol) in dry DMF (75 mL) was cooled in an ice bath and treated with NaH (1.78 g, 44.5 mmol, 60% oil dispersion). After 30 min, the red reaction mixture was treated over 5 min with ethyl bromoisobutyrate (7.4 mL, 50 mmol). The cold bath was removed after 5 min. The reaction was stirred 20 min and placed in an oil bath (T=85° C.). After 18 h, the mixture was cooled and partitioned between brine (75 mL) and ether (200 mL). The organic layer was washed with brine (50 mL), dried (Na2SO4), and concentrated to a brown oil (12 g). The crude product was purified by flash chromatography using hexanes:ethyl acetate (100:0 to 5:1) to give the desired product (8.47 g, 95%).

1. customthe red reaction mixture
2. customThe cold bath was removed after 5 min
3. customplaced in an oil bath
4. custom(T=85° C.)
5. waitAfter 18 h
6. temperaturethe mixture was cooled
7. custompartitioned between brine (75 mL) and ether (200 mL)
8. washThe organic layer was washed with brine (50 mL)
9. dry with materialdried (Na2SO4)
10. concentrationconcentrated to a brown oil (12 g)
11. customThe crude product was purified by flash chromatography