Diethyl Ether → 3-Fluoro-p-anisaldehyde

Participants

Reaction Conditions

Reaction Steps

A solution of o-fluoroanisole, 101 g (0.80 mol) in 500 ml dry methylene chloride is added dropwise over 30 minutes to a solution of titanium tetra-chloride, 182 g (0.96 mol, 1.2 equiv.) and α,α-dichloromethylmethyl ether, 110 g (0.96 mol) in an equal volume of methylene chloride. The temperature is maintained at 10-20° C. with an ice-bath. The mixture is stirred at room temperature for 1 hour longer and then poured over crushed ice-water with stirring. Ether (1) is added, and the mixture stirred under nitrogen until solution occurs. The organic layer is extracted with water (3×), with sodium bicarbonate solution (3×) and is dried (MgSO4). The solvent is evaporated at 30° C. to give an oily crude product, which is distilled in vacuo through a jacketed Vigreux column to give 3-fluoro-4-methoxybenzaldehyde, B.P. 120-121° C. (10 mm Hg) Rf 0.6 on a silica-gel G with methylene chloride.

Provenance & Evidence