Acetic Acid → 2-[3,5-Dichloro-4-(5-isopropyl-1-methyl-6-oxo-1,6-dihydro-pyridazin-3-yloxy)-phenyl]-3,5-dioxo-2,3,4,5-tetrahydro-[1,2,4]triazine-6-carbonitrile

Participants

Reaction Steps

A solution of (2-cyano-2-{[3,5-dichloro-4-(5-isopropyl-1-methyl-6-oxo-1,6-dihydro-pyridazin-3-yloxy)-phenyl]-hydrazono}-acetyl)-carbamic acid ethyl ester (68) (6.5 g, 13.12 mmol) and potassium acetate (1.42 g, 14.43 mmol) in N,N-dimethylacetamide was heated to 120° C. for 2 h. At this time, the reaction was cooled to room temperature and was treated with glacial acetic acid (1.5 mL) and water (65 mL). The mixture was stirred at room temperature for 15 min. The solids which resulted were collected by filtration, washed with water (65 mL) and dried under vacuum to give an orange solid. The solid was suspended in acetonitrile (36 mL), heated to reflux for 3 h and then cooled to room temperature. The resulting solids were then collected by filtration, washed with acetonitrile (12 mL) and methyl tert-butyl ether (24 mL) and dried under vacuum to afford 2-[3,5-dichloro-4-(5-isopropyl-1-methyl-6-oxo -1,6-dihydro-pyridazin-3-yloxy)-phenyl]-3,5-dioxo-2,3,4,5-tetrahydro[1,2,4]triazine-6-carbonitrile (69) (5.06 g, 85.8%) as an orange solid; ES(+)-HRMS m/e calcd for C18H14Cl2N6O4 (M+H)+ 449.0527, found 449.0527. Exact Mass=448.0454; Molecular Weight=449.26.

Provenance & Evidence