Ethyl orthoformate → Ethyl (3,5-dichloropyridazin-4-yl)imidoformate

Participants

Reaction Steps

To a stirred suspension of 3,5-dichloro-4-aminopyridazine (5 g, 31 mmol) in triethyl orthoformate (205 mL) was added pyridinium para-toluenesulfonate (387 mg, 1.5 mmol) and the resultant solution was heated at 100° C. for 16 hours. The reaction mixture was cooled to room temperature then evaporated in vacuo and the crude residue was purified by silica gel column chromatography eluting with hexane:EtOAc (80:20) to afford the title compound as a light brown oil in 60% yield, 4 g.

Provenance & Evidence