反应详情

A solution of 3′-fluoro-4′-methoxyacetophenone (10 g; 59 mmol) and m-chloroperbenzoic acid (50% purity; 30 g; 89 mmol) in CH2Cl2 (300 mL) was stirred at RT overnight. The solution was washed with saturated aqueous Na2CO3, then filtered through a pad of SiO2 (CH2Cl2 as eluent) and finally chromatographed (SiO2; hex:EtOAc 4:1) to give the crude product (3′-fluoro-4′-methoxy phenyl acetate; 63 g). A solution of this crude material and LiOH.H2O (5 g; 120 mmol) in MeOH:H2O (100 mL of a 9:1 mixture) was stirred at RT overnight. Volatiles were removed in vacuo, and the residue was partitioned between excess aqueous 1 M HCl and EtOAc (aqueous layer pH˜3). The aqueous phase was extracted with EtOAc (2×). The combined organic extracts were dried (Na2SO4) and concentrated in vacuo to give 3-fluoro-4-methoxy phenol (6.1 g; 72%) as an oil.

1. washThe solution was washed with saturated aqueous Na2CO3
2. filtrationfiltered through a pad of SiO2 (CH2Cl2 as eluent)
3. customfinally chromatographed (SiO2; hex:EtOAc 4:1)
4. customto give the crude product (3′-fluoro-4′-methoxy phenyl acetate; 63 g)
5. customVolatiles were removed in vacuo
6. customthe residue was partitioned between excess aqueous 1 M HCl and EtOAc (aqueous layer pH˜3)
7. extractionThe aqueous phase was extracted with EtOAc (2×)
8. dry with materialThe combined organic extracts were dried (Na2SO4)
9. concentrationconcentrated in vacuo