Diethyl methylmalonate → 2-Ethyl-5-nitropyridine

Participants

Reaction Steps

Diethyl methylmalonate (52.2 g) was added dropwise to a suspension of sodamide (11.7 g) in dry THF (150 ml) with stirring at ambient temperature under nitrogen. The mixture was boiled under reflux for 1 hour and then a solution of 2-chloro-5-nitropyridine (47.7 g) in dry THF (150 ml) was added dropwise cautiously with stirring. After the addition the mixture was boiled under reflux for 3 hours, then cooled and evaporated to remove approximately 80% of the solvent. The residue was poured into water (1 l) and extracted with ether to give an oil which partially crystallised on standing. A mixture of the residue, concentrated sulphuric acid (50 ml) and water (25 ml) was boiled under reflux for 4 hours then cooled in ice and neutralised using concentrated aqueous sodium hydroxide solution. The mixture was left to stand at ambient temperature for 64 hours and then filtered to give a solid which was extracted continuously with dichloromethane in a soxhlet extractor. The dichloromethane was cooled, dried and evaporated. The residue was filtered and the filtrate was distilled under vacuum to give 2-ethyl-5-nitropyridine, b.p. 82°-92° C. at 1 mm Hg.

Provenance & Evidence