1,4-Dioxane → 5-(Pyridin-2-yl)pyridin-2-amine

Participants

Reaction Conditions

Reaction Steps

To a reaction tube were added 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amine (220 mg, 1.00 mmol), 2-iodopyridine (205 mg, 1.00 mmol), Pd(PPh3)4 (57.7 mg, 0.05 mmol) and K3PO4 (424 mg, 2.00 mmol). The tube was subjected to vacuum and back filled with argon. Dioxane (3.0 ml) and water (0.3 ml) were added and the mixture was heated at 96° C. overnight. After cooled to room temperature, the reaction mixture was filtered through celite (washed with ethyl acetate) and concentrated by evaporation. The residue was redistributed between ethyl acetate (40 ml) and 0.1 N HCl solution (40 mL). The acidic aqueous phase was further extracted with ethyl acetate (40 ml×2) and treated with Na2CO3 to have pH around 9 and concentrated by evaporation of water. The solid residue was extracted with refluxing ethyl acetate (40 ml) to give 2,3′-bipyridin-6′-amine (124-1) which is used for reaction without further purification.

Provenance & Evidence