反应详情

A solution of (R)-2-amino-2-(5-bromo-2-fluoro-phenyl)-propan-1-ol (5.0 g, 20.2 mmol) and 4-methoxybenzaldehyde (2.8 g, 20.2 mmol) in 1,2-dichloroethane (150 ml) was treated with sodium triacetoxyborohydride (8.81 g, 40.3 mmol) at room temperature. TLC check (eluent: heptane:ethyl acetate=1:1) showed complete reaction after 30 minutes. For the workup, to the reaction mixture were added ethyl acetate (250 ml) and saturated sodium hydrogen carbonate solution (100 ml). The aqueous layer was separated, then extracted with ethyl acetate (250 ml). The combined organic layers were washed with saturated sodium chloride solution (100 ml), thereafter dried over sodium sulfate and evaporated at reduced pressure. After chromatography on Silicycle-Si-amine column using a gradient of heptane and ethyl acetate=100/0 to 50/50 as the eluent, (R)-2-(5-bromo-2-fluoro-phenyl)-2-(4-methoxy-benzylamino)-propan-1-ol (intermediate C7A) was obtained as a colourless oil (7.29 g, 98% of theory). MS (ISP): m/z=368.1, 370.1 [M+H]+.

1. customreaction after 30 minutes
2. customThe aqueous layer was separated
3. extractionextracted with ethyl acetate (250 ml)
4. washThe combined organic layers were washed with saturated sodium chloride solution (100 ml)
5. dry with materialdried over sodium sulfate
6. customevaporated at reduced pressure