4-Aminopyridine → HCID 87536091, compound

Participants

Reaction Steps

A solution of pyridine-4-ylamine (4.5 g, 47.81 mmol) in 85% phosphoric acid (30 ml) and 65% nitric acid (20 ml) was cooled to −10° C. and treated with solid sodium nitrite (3.3 g, 47.8 mmol) over 20 mins. Ice (50 g) was added and the mixture added at 0° C. to a suspension of 2,4-pentadione (4.79 g; 47.8 mmol) and potassium acetate (40 g) in EtOH (280 ml). After completion, 20% aq. Na2CO3 (300 ml) was added at 0° C. until pH reached 7 and the solution extracted with dichloromethane (3×400 ml), dried, concentrated and chromatographed on silica gel with dichloromethane/methanol to give the product as a yellow solid (5.3 g, 54%).

Provenance & Evidence