Formaldehyde → 4-Bromo-2-hydroxybenzaldehyde

Participants

Reaction Conditions

Reaction Steps

A solution of 3-bromophenol (100.00 g, 0.576 mol) in a mixture of 600 mL of toluene/acetonitile (2:1) was added MgCl2 (110.6 g, 3.68 mol), paraformaldehyde (40.00 g) and the mixture was maintained at 80° C. for 1.5 h while the by-product was distilled off. A second portion of paraformaldenhyde (40.00 g) was added and the mixture was stirred for 2.5 h at 80° C., and the third portion of paraformaldenhyde (30.6 g) was added and stirred for 2 h at 80° C. The reaction was quenched with cool 2.5 N hydrochloride acid, and the mixture was stirred at room temperature for 1 h to afford a biphasic solution. The aqueous phase was extracted with EtOAc. And the combined organic extracts were washed with brine, dried over anhydrous sodium sulfate and concentrated. The residue was purified by silica gel column chromatography to afford 4-bromo-2-hydroxybenzaldehyde. 1H-NMR (400 MHz, CDCl3) 11.10 (s, 1H), 9.86 (s, 1H), 7.40˜7.43 (d, J=8.4 Hz, 1H), 7.15˜7.20 (m, 2H).

Provenance & Evidence