Diethyl Malonate → Acetic Anhydride

Participants

Reaction Steps

Malonic acid diethyl ester (8.5 g) was dissolved in dimethylformamide (75 mL) followed by addition of potassium tert-butoxide (5.9 g). After stirring for 15 min at room temperature, a solution of 3-chloromethyl-7-chloro-4-methylbenzofuran (3.8 g, prepared analogously to the 5-fluoro analogue as described in Example, 2) in dimethylformamide (25 mL) was added dropwise. After stirring for 2 hours the reaction mixture was poured onto ice-water. Standard work-up with acetyl acetate gave a yellow oil (10 g) of diethyl 2-(7-chloro-4-methylbenzofuran-3-yl)malonate, sufficiently pure for further synthesis.

Provenance & Evidence