Bromine → 5-(Benzyloxy)-2-hydroxybenzaldehyde

Participants

Reaction Steps

To a mixed suspension of magnesium (305 mg, 12.6 mmol) in diethyl ether (7.5 mL) and toluene (7.5 mL) was added bromine (354 μL, 6.91 mmol) at 0° C., which was stirred at room temperature for 5 minutes under nitrogen atmosphere and was refluxed while heating for 5 minutes. After the reaction mixture was cooled to room temperature, a toluene (20 mL) solution of 2,5-bis-benzyloxy-benzaldehyde (2.00 g, 6.28 mmol) described in Production Example 7-1-1 were added followed by stirring at room temperature for 24 hours under nitrogen atmosphere. Moreover, after stirring for 6 hours while refluxing while heating, the reaction mixture was cooled to room temperature. The precipitated solid was filtered out and washed with toluene. 1 N aqueous hydrochloric acid solution (20 mL) was added to the filtered solid followed by stirring for 1 hour while refluxing and heating. The reaction solution was allowed to cool to room temperature followed by extraction with ethyl acetate. The organic layer was washed with sat. NaCl followed by drying over anhydrous magnesium sulfate and filtering. The filtrate was concentrated under a reduced pressure and the residue was purified by silica gel column chromatography (heptane:ethyl acetate=1:1) to obtain the title compound (830 mg, 58%) as a pale yellow solid.

Provenance & Evidence