Hydrazine → Pyrido(2,3-d)pyridazine-5,8-diol

Participants

Reaction Conditions

Reaction Steps

To 25 mL of acetic acid at 100° C. was added 2,3-pyridinedicarboxylic anhydride (5.00 g, 34 mmol). Once the solution was homogeneous, it was removed from the oil bath and anhydrous hydrazine (2.0 ml, 64 mmol) was added dropwise over 5 minutes. The reaction was returned to reflux. After 3 min, the solution crystallized and became a solid mass. The reaction was heated in a 125° C. bath for 10 minutes then cooled to room temperature. The solid was transferred to a Büchner funnel and washed with 2×10 mL of acetic acid. The solid was dried under high vacuum to afford 6,7-dihydropyrido[2,3-d]pyridazine-5,8-dione 77. 1H-NMR (400 MHz, DMSO): δ 9.10 dd, J=4.7, 2.0 Hz, 1H), 8.50 (dd, J=7.8, 1.6 Hz, 1H), 7.86 (dd, J=8.2, 4.7 Hz, 1H).

Provenance & Evidence