Formaldehyde → 3,4,6-Trifluoro-2-methoxybenzaldehyde

Participants

Reaction Steps

Paraformaldehyde (0.960 g, 0.01066 mol) and magnesium dichloride (0.505 g, 0.005304 mol) were suspended in THF (10.0 mL). Triethylamine (0.75 mL, 0.0054 mol) was added and the mixture was stirred under nitrogen for 10 minutes. Then 2,3,5-trifluorophenol (0.524 g, 0.00027 mol) was added and the reaction mixture was stirred at refluxed for 16 hours. The reaction mixture was subjected to filtration and the filtrate was diluted with an aqueous solution of hydrochloric acid (2.0 M, 15 mL). The product was then extracted with tert-butyl methyl ether (20 mL). The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo. The crude was dissolved in DMF (5.0 mL). Then potassium carbonate (0.55 g, 0.003979 mol) and methyl iodide (0.175 mL, 0.00072 mol) were added to the mixture, which was stirred at 50° C. under nitrogen for 3 hours, then left to stir at room temperature for 72 hours. The reaction was diluted in an aqueous solution of saturated brine (15 mL) and extracted with tert-butyl methyl ether (20 mL). The organics were combined, dried over sodium sulfate, filtered, and concentrated in vacuo. The resulting crude was purified by silica gel chromatography eluting with 0 to 10% EtOAc in heptane to yield the title compound as a colourless oil (0.080 g, 0.432 mmol).

Provenance & Evidence