Acetic Anhydride → 2-Chloro-3-nitro-6-acetoxymethylpyridine

Temperatur

60 °C

2-Chloro-3-nitro-6-picoline-N-oxide (1.6 g, 8.5 mmol) was dissolved in acetic anhydride (5 mL) and the solution was heated in a 60° C. oil bath for 3 hours. The solvents were removed under vacuum and the dark residue was partitioned between methylene chloride (30 mL) and saturated aqueous potassium carbonate (100 mL). The aqueous layer was re-extracted with more methylene chloride (2×40 mL) and the combined methylene chloride layers were dried with magnesium sulfate, filtered and evaporated under vacuum. The crude solid was dissolved in methylene chloride (5 mL) and was loaded onto a silica gel column (E. Merck 60, 230-400 mesh, 2.5×24 cm). The column was eluted with methylene chloride collecting 8 mL fractions. Fractions 11-26 were combined and evaporated to give the title compound (0.42 g) as a white solid.

1. customThe solvents were removed under vacuum
2. customthe dark residue was partitioned between methylene chloride (30 mL) and saturated aqueous potassium carbonate (100 mL)
3. extractionThe aqueous layer was re-extracted with more methylene chloride (2×40 mL)
4. dry with materialthe combined methylene chloride layers were dried with magnesium sulfate
5. filtrationfiltered
6. customevaporated under vacuum
7. dissolutionThe crude solid was dissolved in methylene chloride (5 mL)
8. washThe column was eluted with methylene chloride collecting 8 mL fractions
9. customevaporated

ORD-Eintrag

ord-a6b640a72bc147f9991c6f4849570262

Quelldatensatz

uspto-grants-1996_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05541176