Hydrochloric Acid → 5-tert-Butyl-4-hydroxy-2-methylbenzaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Aluminum chloride (26.6 gm, 200 mmol) was added to chlorobenzene (40 mL) and the mixture stirred and cooled to −10° C. A solution of 2-tert-butyl-5-methylphenol (16.4 gm, 100 mmol) in triethyl orthoformate (32.5 gm, 220 mmol) was added dropwise. On completion of the addition, the reaction mixture was warmed to 0-5° C. and held for 6 hours. Hydrochloric acid (100 mL of a 5% solution) was added to the reaction mixture. The mixture was extracted with (1:1) ethyl acetate/toluene (200 mL). The organic phase was extracted with 23% potassium hydroxide (3×50 mL) and water (25 mL) and the water extract combined with the three potassium hydroxide extracts. The pH of the combined extracts was adjusted to 4 with 37% hydrochloric acid. The resulting precipitate was collected and washed with water (3×50 mL) and vacuum dried 55° C. to give 5-tert-butyl-4-hydroxy-2-methylbenzaldehyde (1): 14.8 g (77 mmol, 77%): mp: 171-172° C.

Herkunft & Nachweise