1-Bromo-2-naphthol → 1-(3-Chloro-2-fluorophenyl)-2-naphthol

Participants

Reaction Steps

In a 200-mL three-neck flask were put 5.8 g (26 mmol) of 1-bromo-2-naphthol, 4.5 g (26 mmol) of 3-chloro-2-fluorobenzeneboronic acid, and 0.40 g (1.3 mmol) of tri(ortho-tolyl)phosphine, and the air in the flask was replaced with nitrogen. To this mixture, 150 mL of toluene, 50 mL of ethanol, and 21 mL of an aqueous solution of potassium carbonate (2.0 mol/L) were added. The mixture was degassed by being stirred while the pressure in the flask was reduced; then, the air in the flask was replaced with nitrogen. To this mixture was added 58 mg (0.26 mmol) of palladium(II)acetate, and the resulting mixture was stirred at 90° C. under a nitrogen stream for 7 hours. After stirring, the organic layer of the mixture was washed with water and the aqueous layer was subjected to extraction with toluene. The solution of the extract combined with the organic layer was washed with a saturated aqueous solution of sodium chloride, and the organic layer was dried over magnesium sulfate. The resulting mixture was gravity-filtered, and the resulting filtrate was concentrated to give a brown liquid. The liquid was purified by silica gel column chromatography using a mixed solvent (toluene: hexane=9:1) as a developing solvent, so that 3.1 g of a brown liquid of a target substance was produced in a yield of 44%.

Provenance & Evidence