Sodium Hydroxide → HCID 21187496, compound

Participants

Reaction Steps

To a solution of 6-chloro-3,7-diphenyl-1,2,4-triazolo[4,3-b]pyridazine (from Example 2, Step c) (1.02 g, 3.34 mmol) in 1,4-dioxane (60 ml) and water (12 ml) was added 4 M aqueous NaOH (4.17 ml, 16.7 mmol), and the solution was heated at reflux for 7.5 h whilst stirring magnetically. The mixture was then concentrated in vacuo and the aqueous residue was partitioned between water (200 ml) and diethyl ether (100 ml). The aqueous layer was then acidified with 5 M aqueous HCl until the pH was ca. 3. The resulting precipitated solid was collected by filtration, washed with water, then hexane, and dried at 60° C. under vacuum to give 0.8885 g (92%) of the title compound as a white solid. 1H NMR (360 MHz, d6-DMSO) δ 7.47-7.63 (6H, m), 7.71 (2H, dd, J=8.0, J=1.8 Hz), 8.31 (1H, s), 8.46 (2H, m), 12.80 (1H, br s); MS (ES+) m/e 289 [MH]+.

Provenance & Evidence