Hydrazine hydrate (1:1) → HCID 66966126, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 3-picolinoylpicolinate 7, (240 mg, 0.99 mmol), hydrazine hydrate (63 μL, 1.3 mmol) and 12 mL of absolute ethanol was heated to 75° C. in a sealed tube for 1 h. After cooling, the solid was collected by vacuum filtration and dried under air suction. The mother liquor was concentrated to dryness under reduced pressure and purified by normal phase flash chromatography eluting with 0-10% methanol in dichloromethane over approximately 20 minutes. Like fractions were combined and concentrated under reduced pressure and combined with the solid collected by filtration to give 8-(pyridin-2-yl)pyrido[2,3-d]pyridazin-5(6H)-one 9 (150 mg, 0.67 mmol). 1H NMR (400 MHz, Methanol-d4) δ 9.07 (dd, J=4.5, 1.6 Hz, 1H), 8.98 (dd, J=8.4, 1.6 Hz, 1H), 8.72 (ddd, J=4.9, 1.7, 1.0 Hz, 1H), 8.00 (ddd, J=7.9, 7.3, 1.7 Hz, 1H), 7.99-7.92 (m, 1H), 7.97-7.84 (m, 1H), 7.53 (ddd, J=7.3, 4.9, 1.5 Hz, 1H). LCMS: (M+H)+, 225.

Provenance & Evidence