Diethyl Malonate → Ethyl 7-(4-methoxybenzyl)-1-methyl-2,8-dioxo-1,2,7,8-tetrahydropyrido[2,3-d]pyridazine-3-carboxylate

Participants

Reaction Steps

A mixture of 1-(4-methoxybenzyl)-5-(methylamino)-6-oxo-1,6-dihydropyridazine-4-carbaldehyde (4) (3.78 g, 13.8 mmol), diethyl malonate (4.20 mL, 27.7 mmol), piperidine (1.44 mL, 14.5 mmol), and EtOH (100 mL) was stirred at reflux in an oil bath for 5 h. The reaction mixture was allowed to stand at RT for 18 h to afford a suspension. The solid was collected by suction filtration, washed with EtOH (10 mL), and dried in vacuo to afford ethyl 7-(4-methoxybenzyl)-1-methyl-2,8-dioxo-1,2,7,8-tetrahydropyrido[2,3-d]pyridazine-3-carboxylate as a tan solid. MS (ESI, pos. ion) m/z: 370 (M+1).

Provenance & Evidence