Hydrazine → 3-Hydrazinyl-4-methyl-6-phenylpyridazine

Participants

Reaction Conditions

Reaction Steps

3,6-Dichloro-4-methylpyridazine (1.00 g, 6.1 mmol) was mostly dissolved in dioxane (22.5 mL) then added phenylboronic acid (0.82 g, 6.7 mmol), PdCl2(dppf)-CH2Cl2Adduct (0.25 g, 0.31 mmol) and a solution of cesium carbonate (6.0 g, 18 mmol) in water (7.5 mL). The reaction mixture was heated at 80° C. for 6 hours. The reaction mixture was concentrated under vacuum and the remaining solid was triturated with water. The solid was collected on a glass frit, washing well with water. The sample was purified by flash chromatography eluting with 1:4 ethyl acetate/hexane to afford 3-chloro-4-methyl-6-phenylpyridazine as an off-white solid. MS (ESI pos. ion) m/z: 205.2 (MH+). Step 2. 3-Chloro-4-methyl-6-phenylpyridazine (0.510 g, 2.49 mmol) was dissolved in hydrazine (1.56 ml, 49.8 mmol) then the reaction mixture was heated at 100° C. for 1.5 hours. The precipitate that had formed in the mixture was collected and washed with iPrOH. The solid was dried under high vacuum to afford 1-(4-methyl-6-phenylpyridazin-3-yl)hydrazine as a pale yellow solid. MS (ESI pos. ion) m/z: 201.1 (MH+). The remaining synthesis of 7-methoxy-N-((8-methyl-6-phenyl-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)methyl)-1,5-naphthyridin-4-amine was conducted as described in general Method B.

Provenance & Evidence