Sodium Carbonate → 3-Chloro-6-(1-methyl-1H-pyrazol-4-yl)pyridazine

Participants

Reaction Conditions

Reaction Steps

A flask was charged with 3,6-dichloropyridazine (Aldrich, 23.91 g, 160.5 mmol), 1-Methyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-pyrazole (20 g, 96 mmol), 2.0 M Na2CO3 (96 mL) and dioxane (65 mL). Nitrogen was bubbled through the reaction for 60 seconds followed by the addition of Dichlorobis(triphenylphosphine)palladium (0) (6.75 g, 9.6 mmol). The reaction was heated to 80° C. overnight followed by aqueous work up using AcOEt and a solution of K2CO3. After filtration over celite, the organic layer was dried (MgSO4) and concentrated in vacuo. A first fraction of compound (10.2 g) was obtained by crystallization in the solvent (dichoromethane). The filtrate was purified by column chromatography (CH2Cl2 100% and CH2Cl2/MeOH: 95/5). The two fractions were gathered and washed with diisopropylether to give the title compound as a yellow solid (12.7 g, 68%).

Provenance & Evidence