Hydrochloric Acid → HCID 178496281, compound

Temperature

0 °C

A solution of 3-aminopyridine (20 g, 210 mmol) in 6 M HCl aqueous solution (200 ml, 1200 mmol) was cooled with ice bath. To the solution was added dropwise a solution of sodium nitrite (18 g, 260 mmol) in water (40 mL). After stirring at 0° C. for 5 min, the mixture was added to a mixture of sodium acetate (130 g, 1300 mmol) and methyl 4-methoxyacetoacetate (28 ml, 210 mmol) in EtOH (300 ml) and water (150 ml) at 0° C., and the mixture was stirred at 0° C. for 1 h. The mixture was diluted with water (150 ml), extracted with AcOEt (500 ml×3). The combined organic layer was washed with saturated NaHCO3 aqueous solution (300 ml×3) and brine (300 ml), dried over Na2SO4, filtered and concentrated under reduced pressure to give the title compound (52 g, 97% yield) as a brown oil: 1H NMR (300 MHz, CDCl3): δ ppm 3.50 (3H×½, s), 3.51 (3H×½, s), 3.89 (3H×½, s), 3.93 (3H×½, s), 4.67 (2H×½, s), 4.70 (2H×½, s), 7.35-7.43 (1H, m), 7.67-7.74 (1H×½, m), 7.84-7.91 (1H×½, m), 8.41-8.49 (1H, m), 8.64-8.71 (1H, m), 12.90 (1H×½, s), 14.76 (1H×½, brs).

1. stirringthe mixture was stirred at 0° C. for 1 h
2. extractionextracted with AcOEt (500 ml×3)
3. washThe combined organic layer was washed with saturated NaHCO3 aqueous solution (300 ml×3) and brine (300 ml)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure

ORD record

ord-8000b259ea504a16bc215dae81d4e818

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08513251B2