Acetic Acid → 3-Ethyl-4-hydroxy-5-methylbenzaldehyde

Participants

Reaction Steps

A solution of 2-ethyl-6-methyl-phenol (8.40 g, 61.7 mmol) and hexamethylene tetraamine (12.97 g, 92.5 mmol) in acetic acid (60 mL) and water (14 mL) is heated to 115° C. The water is distilled off at 117° C. and collected with a Dean-Stark apparatus. Then the water separator is replaced by a reflux condenser and the mixture is refluxed for 3 h. The mixture is cooled to rt, diluted with water (100 mL) and extracted with EA. The org. extract is washed with sat. aq. NaHCO3, dried over MgSO4 and evaporated. The remaining solid is dissolved in EA and treated with heptane to initialize crystallisation. The solid material is collected and dried to give 3-ethyl-4-hydroxy-5-methyl-benzaldehyde (3.13 g) as a colourless crystalline powder, 1H NMR (CDCl3): δ 9.83 (s, 1H), 7.58-7.53 (m, 2H), 5.30 (s br, 1H), 2.69 (q, J=7.6 Hz, 2H), 2.32 (s, 3H), 1.28 (t, J=7.6 Hz, 3H).

Provenance & Evidence