Formaldehyde → 3-tert-Butyl-2-hydroxybenzaldehyde

Participants

Reaction Steps

To a stirred suspension of 2-tert-butylphenol (6)(4.55 g, 30 mmol), magnesium chloride (5.71 g, 60 mmol) and paraformaldehyde (2.08 g, 66 mmol) in THF (120 mL) at room temperature, was added triethylamine (8.35 mL, 60 mmol) dropwise. The reaction was heated to reflux for 3 hours to give an orange suspension. The crude was extracted using EtOAc (3×50 mL). A small amount of diluted HCl can be added if a permanent emulsion is formed. The organic layers were dried over MgSO4 and the volatiles evaporated under low pressure to yield a pale yellow oil which did not need any further purification. It can become dark green on storage. Yield: 90%. Pale yellow oil. 1H-NMR δH (CDCl3, 300 MHz): 1.44 (9H, s, 3×CH3), 6.97 (1H, t, J=7.5 Hz, HAr), 7.41 (1H, dd, J=1.5 Hz, J=7.5 Hz, HAr), 7.54 (1H, dd, J=1.2 Hz, J=7.5 Hz, HAr), 9.88 (1H, s, CHO), 11.82 (1H, s, OH).

Provenance & Evidence