Ethyl Bromide → HCID 66931452, compound

Participants

Reaction Steps

In a three necked round bottom flask under a nitrogen atmosphere at −78° C., a solution of n-butyllithium in hexane (1.6 M, 7 ml, 11.1 mmol) was added dropwise to a solution of diisopropylamine (1.56 ml, 11.1 mmol) in tetrahydrofuran (10 ml). The solution was stirred for 30 minutes, then a solution of 5-chloropyridine-2-carboxylic acid (800 mg, 5.0 mmol) in tetrahydrofuran (50 ml) was added dropwise over 1 hour and the reaction was stirred for 1 hour at −78° C. This solution was added dropwise via cannula to a solution of bromoethane (1.89 ml, 25.3 mmol) in tetrahydrofuran (10 ml) at −30° C. The reaction mixture was stirred overnight at room temperature. For the workup, water (10 ml) was added and the mixture was concentrated; hydrochloric acid (1 N) was added to reach pH 5 and the solution obtained was evaporated to dryness. The solid was solubilized in methanol and poured into acetonitrile. The solid formed was filtered off; the solution was collected and evaporated. The crude product was purified by chromatography to give the 5-chloro-3-ethyl-pyridine-2-carboxylic acid (90 mg, 10% of theory) as a white solid. Mass (calculated) C8H8ClNO2 [185.611]; (found) [M+H]+=185, [M+2-H]+=187.

Provenance & Evidence