Sulfuric Acid → 4-Methoxy-3-nitro-6,7-dihydro-5H-cyclopenta[b]pyridine

Participants

Reaction Conditions

Reaction Steps

4-Methoxy-6,7-dihydro-5H-cyclopenta[b]pyridine (2.90 g, 19.4 mmol) was mixed with concentrated sulfuric acid (17.0 g, 173 mmol) at 0° C., then a mixture of potassium nitrate (5.3 g, 52 mmol) in another portion of concentrated sulfuric acid (26.5 g, 270 mmol) was added slowly. The reaction mixture was heated at 80° C. for 4 h. The crude mixture was slowly poured onto crushed ice (50 g), and neutralized carefully with 50% aq. NaOH to pH 8-9. The resulting mixture was extracted with EtOAc five times. The combined organic extracts were dried and concentrated under reduced pressure to give the crude sub-title compound as brown gum (1.56 g, 41%), which was used without further purification. LCMS calc. for C9H11N2O3 (M+H)+: m/z=195.1. Found: 195.2.

Provenance & Evidence