Potassium Carbonate → 5-Methyl-3-phenylpyridin-2-amine

Participants

Reaction Steps

2-amino-3-phenyl-5-methylpyridine was prepared as follows: 2-amino-5-picoline (10.8 g, 0.1 M) was dissolved in glacial acetic acid (200 ml), and N-bromosuccinamide (20 g, 0.11 M) was added. The reaction mixture was stirred at room temperature for 17 hours. The reaction mixture was poured onto ice/water and the solid removed by filtration. The filtrate was basified with solid sodium hydroxide, and the resulting precipitate was isolated by filtration (12.8 g). The product, 2-amino-3-bromo-5-methylpyridine (3.7 g, 20 mmol), was dissolved in anhydrous DMSO (100 ml) under an atmosphere of nitrogen. Phenylboronic acid (2.66 g, 22 mmol) was added, followed by the addition of potassium carbonate (9.66 g, 70 mmol) and bis(triphenylphosphine)-palladium(II) chloride (426 mg, 0.6 mmol). The reaction mixture was heated to 80° C. with stirring for 15 hours. The reaction was cooled, poured into ice/water, and the crude product was collected by filtration. The resultant material was treated with 1 M aqueous hydrochloric acid (200 ml), stirred for 10 minutes, and filtered to remove insoluble residues. The filtrate was basified with solid sodium hydroxide, and the resultant yellow precipitate was filtered and dried to provide the product, 2-amino-3-phenyl-5-methylpyridine, as a pale yellow solid (2.25 g).

Provenance & Evidence