Hydrochloric Acid → 2,4-Dihydroxy-3-methylbenzaldehyde

Participants

Reaction Steps

To an ice-cooled solution of POCl3 (4.9 g, 32.2 mmol) in dry DMF (10.0 mL, 64.4 mmol) was slowly added a solution of 2-methylresorcinol (2.0 g, 16.1 mmol) in dry DMF (5.0 mL). After stirring at room temperature for 12 h, the mixture was cooled to 0° C. and then carefully treated with iced water (15 mL). 2 M sodium hydroxide was added to adjust pH to 10. The resulting mixture was heated to reflux for 10 min. Then, the mixture was acidified by 3 M HCl (pH=3). The resulting solid was collected by filtration, and the precipitate was washed with water (10 mL×3). The obtained orange solid (4.0 g, 46%) was dried in vacuo and used for the next reaction without further purification. 1H-NMR (DMSO-d6, 400 MHz): δ9.71 (1H, s), 7.43 (1H, d, J=8.5 Hz), 6.55 (1H, d, J=8.5 Hz), 1.97 (3H, s).

Provenance & Evidence