反应详情

The benzylether from stage (iii) (9.27 g, 39.5 mmol) was dissolved in DCM (5 mL), ethanethiol (5 mL) and BF3.OEt2 (5 mL, 39.5 mol) were then added at room temperature under a nitrogen atmosphere. The mixture was stirred overnight before the reaction was quenched with hydrochloric acid (2 M) and stirred for a further 30 mins. The mixture was then basified by the addition of sodium hydroxide (2 M) until pH 10 was attained. The mixture was then washed with ethyl acetate (3×50 mL). The aqueous layer was reacidified by the addition of hydrochloric acid (2 M) to pH 1 and extracted with ethyl acetate (4×50 mL). The extracts were combined, dried (MgSO4) and evaporated to an oil. Purification by flash chromatography [SiO2; EtOAc/ pentane (1:9→1:4)] afforded the desired phenol compound as a colourless solid (1.73 g, 28%); δH(CDCI3, 400 MHz) 2.21 (3 H, s), 3.70 (3 H, s), 6.30 (1 H, d), 6.35 (1 H, s), 6.96 (1 H, d), 9.39 (1 H, brs)

1. customwas quenched with hydrochloric acid (2 M)
2. stirringstirred for a further 30 mins
3. additionThe mixture was then basified by the addition of sodium hydroxide (2 M) until pH 10
4. washThe mixture was then washed with ethyl acetate (3×50 mL)
5. additionThe aqueous layer was reacidified by the addition of hydrochloric acid (2 M) to pH 1
6. extractionextracted with ethyl acetate (4×50 mL)
7. dry with materialdried (MgSO4)
8. customevaporated to an oil
9. customPurification by flash chromatography [SiO2; EtOAc/ pentane (1:9→1:4)]