3-Aminopyridine → 3-(Pyridin-3-ylamino)-4-ethoxy-cyclobut-3-ene-1,2-dione

Participants

Reaction Steps

To a solution of 3,4-diethoxy-3-cyclobutene-1,2-dione (5.00 g, 29.4 mmol) in absolute ethanol (100 mL) was added a suspension of 3-aminopyridine (2.77 g, 29.4 mmol) in ethanol (50 mL). The mixture was heated at reflux for 18 hours, then concentrated. Chromatography (4:1 EtOAc/hexane) afforded 3.15 g (49%)of a white solid: mp 140°-145° C.

Provenance & Evidence