1,1-Dibromoethane → 4-(4-t-Butyldimethylsilyloxyphenyl)-4-hydroxy-7-methoxymethyloxy-3-[4-(methoxymethyloxy)phenyl]-3-methylthiochroman

Participants

Reaction Conditions

Reaction Steps

Under argon atmosphere dibromoethane (0.11 ml, 1.28 mmol) was added dropwise to tetrahydrofuran suspension (5 ml) of magnesium turning (224 mg, 9.33 mmol) and the mixture was stirred for 10 minutes at 60° C. At the same temperature, tetrahydrofuran solution (5 ml) of p-bromo-t-butyldimethylsilyloxybenzene (2.30 g, 8.01 mmol) was added dropwise thereto and the mixture was heated under refluxing for 1.5 hours. To the resulting solution was added dropwise tetrahydrofuran solution (5 ml) of 7-methoxymethyloxy-3-[4-(methoxymethyloxy)phenyl]-3-methylthiochroman-4-one (1.00 g, 2.67 mmol) and the mixture was heated under refluxing for 3 hours. After adding saturated aqueous ammonium chloride solution, the reaction solution was extracted with ethyl acetate, and the organic layer was washed with saturated saline, dried over anhydrous magnesium sulfate and then distilled under reduced pressure to remove the solvent. The crude product thus obtained was purified with silica gel column chromatography (ethyl acetate:hexane=1:4) to obtain 1.29 g (yield: 83%) of the title compound.

Provenance & Evidence