Dimethylformamide → 3-Chloro-5-methoxybenzaldehyde

Participants

Reaction Conditions

Reaction Steps

3,5-Dichloroanisole (74.0 g, 419 mmol) in THF (200 ml) was added dropwise to magnesium metal (14.2 g, 585 mmol, pre-washed with 0.5 N HCl) in THF (100 mL) at 25° C. After the addition, 1,2-dibromoethane (3.9 g, 20.8 mmol) was added dropwise. The resultant dark brown mixture was heated at reflux for 3 h. The mixture was cooled to 0° C., and N,N-dimethylformamide (60 mL) was added in one portion. The mixture was partitioned with diethyl ether (3×400 μL) and 6N HCl (500 mL). The combined organic extracts were washed with brine (300 mL), dried (Na2SO4), filtered and concentrated in vacuo to give an oil. Flash chromatography (2×) on silica gel eluting with Hex:EtOAc (4:1) afforded the sub-title compound (38.9 g, 54%) as a yellow oil.

Provenance & Evidence