Hydrochloric Acid → HCID 12070454, compound

Participants

Reaction Steps

To a suspension of magnesium (0.5 g) in THF (7 ml), a solution of 1-bromo-4-ethoxybenzene (4.0 g) in THF (2.5 ml) was added slowly at room temperature under an argon atmosphere, and the resulting solution was stirred for 1 hour. Subsequently, a solution of trimethoxyborane (2.1 g) in THF (2.5 ml) was added dropwise at −10 to 10° C., and after further addition of THF (7 ml), the reaction mixture was stirred at the same temperature for 1 hour. The reaction mixture was allowed to warm to room temperature and tetrakistriphenylphosphine palladium (115 mg), 5-bromo-2-hydroxybenzaldehyde (2.0 g) and an aqueous solution of tripotassium phosphate (11.1 g) in water (15 ml) were added, and the resulting mixture was stirred under reflux for 1 hour. After the mixture was allowed to cool to room temperature, 6N hydrochloric acid (20 ml) was added dropwise, and then toluene(20 ml) was added. After separation, the aqueous phase was further extracted with toluene (30 ml). The organic layers were combined and washed with aqueous 10% sodium chloride solutions (10 ml×3), dried over anhydrous magnesium sulfate and concentrated. The concentrate was purified by silica gel chromatography (n-hexane/ethyl acetate=6/1), and the appropriate eluate was concentrated. Diisopropylether (15 ml) was added to the concentrate and the resulting mixture was heated under reflux, and then allowed to cool to room temperature. n-Hexane (15 ml) was added to the solution, and stirred at room temperature for 1 hour and at 0° C. for 0.5 hour. The precipitated crystal was collected by filtration and washed with diisopropylether/n-hexane (1/1.4 ml) which was previously cooled to 0 to 5° C. Drying under reduced pressure (room temperature, 2 hours) gave yellow crystal of the title compound (1.8 g, yield 73%).

Provenance & Evidence