2,6-Di-tert-butyl-4-methylphenol → 4-Vinylbenzaldehyde

Participants

Reaction Steps

A few crystals of 2,6-di-tert-butyl-4-methylphenol (BHT), 4-Bromobenzaldehyde (2.00 g, 10.8 mmol), and tetrakis(triphenylphosphine) palladium(0) (250 mg, 2 mol %) are dissolved in toluene (20 mL). Tri-n-butyl-vinyl tin(IV) (3.47 mL, 3.77 g, 11.9 mmol) is added and the mixture is heated to reflux for 3 hr. After cooling to room temperature, the dark green/black reaction mixture is treated as follows: pyridine (4.4 mL) is added, then 9.3 mL of pyridinium hydrofluoride in tetrahydrofuran (˜1.2N, made by adding 0.88 g of pyridinium polyhydrofluoride into 20 mL dry THF containing 3.13 g of pyridine); the mixture is then stirred at room temperature overnight. The treated reaction mixture is diluted with diethyl ether (200 mL), washed with water (50 mL), 10% aqueous hydrochloric acid (2×50 mL), saturated aqueous NaHCO3 (50 mL), and then dried over MgSO4. Concentration in vacuo gives a crude oil, which is purified by flash chromatography (silica, 10% ethyl acetate/hexanes) to give pure 4-vinylbenzaldehyde as a pale yellow oil (1.16 g, 81.3%).

Provenance & Evidence