Benzaldehyde → 4-(Benzylamino)-2-(3,4-dichlorophenyl)-1-(4-methoxyphenoxy)butan-2-ol

Participants

Reaction Steps

To a solution of (2RS)-4-amino-2-(3,4-dichlorophenyl)-1-(4-methoxyphenoxy)butan-2-ol (6.7 g) in methanol (20 mL) were added magnesium sulfate (3.35 g), triethylamine (1.3 mL) and benzaldehyde (2.1 ml), and the mixture was stirred at room temperature for 1.5 hr. To the reaction mixture was added sodium borohydride (3.55 g), and the mixture was stirred at 0° C. for 10 min, and then stirred while warming to room temperature for 1.5 hr. The reaction mixture was filtered through celite, and the filtrate was concentrated. The concentrated residue was diluted with water, and the mixture was extracted with ethyl acetate. The obtained extract was washed with brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure to give 4-(benzylamino)-2-(3,4-dichlorophenyl)-1-(4-methoxyphenoxy)butan-2-ol (8.47 g). To a solution of 4-(benzylamino)-2-(3,4-dichlorophenyl)-1-(4-methoxyphenoxy)butan-2-ol (8.47 g) in THF (45 mL) were added triethylamine (2.85 mL) and chloroacetyl chloride (1.64 ml), and the mixture was stirred at 0° C. for 10 min, and then stirred while warming to room temperature for 2 hr. The reaction mixture was diluted with water, and the mixture was extracted with ethyl acetate. The obtained extract was washed with brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give the title compound (7.41 g).

Provenance & Evidence