Piperidine → ethyl 2-amino-3-cyano-9-hydroxy-4-(3-nitrophenyl)-4H-naphtho[1,2-b]pyran-8-carboxylate

Participants

Reaction Steps

To a solution of ethyl 3,5-dihydroxynaphthalene-2-carboxylate (4.5 g) in ethanol (40 ml) was added 3-nitrobenzylidenemalonitrile (3.9 g) and piperidine (1.95 ml). The mixture was heated under reflux for 15 minutes whereupon a yellow precipitate was observed to form. The mixture was allowed to cool to room temperature, diluted with ether (100 ml) and the solid filtered off to yield ethyl 2-amino-3-cyano-9-hydroxy-4-(3-nitrophenyl)-4H-naphtho[1,2-b]pyran-8-carboxylate as a yellow powder, m.p. 260°-261° C. (dec.)

Provenance & Evidence