Ethyl Bromide → HCID 66931452, compound

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.

1. stirringthe reaction was stirred for 1 hour at −78° C
2. stirringThe reaction mixture was stirred overnight at room temperature
3. concentrationthe mixture was concentrated
4. additionhydrochloric acid (1 N) was added
5. customthe solution obtained
6. customwas evaporated to dryness
7. additionpoured into acetonitrile
8. customThe solid formed
9. filtrationwas filtered off
10. customthe solution was collected
11. customevaporated
12. customThe crude product was purified by chromatography

ORD record

ord-0b6db9ed53bd41e9ae086422be64f225

Source dataset

uspto-grants-2012_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08188079B2