1,2-Dibromoethane → Dimethyl 1-(2-bromoethyl)-1H-pyrazole-3,5-dicarboxylate

Participants

Reaction Steps

A solution of this ester (5.0 g, 27.2 mmol) in 150 ml of anhydrous acetonitrile was treated with K2CO3 (5.2 g, 40.0 mmol) and 1,2-dibromoethane (25.0 ml, 291 mmol). The resulting mixture was heated to reflux under argon. After 25 min the reaction suspension was cooled, filtered and the filtrate evaporated to dryness at reduced pressure and placed on a high vacuum line for 12 h. The resulting white solid was recrystalized from hexane to give 3-2 as a white solid.

Provenance & Evidence