2587-02-2

White solid

4-Amino-2,6-dichloropyridine is a compound useful in organic synthesis used in the synthesis of Rho kinase inhibitors.

The general procedure for the synthesis of 4-amino-2,6-dichloropyridine from 2,6-dichloro-4-nitropyridine was as follows: to a solution of 2,6-dichloro-4-nitropyridine (14.82 g, 76.79 mmol) in ethanol (350 mL) was added sequentially iron powder (19.91 g, 356.58 mmol), water (65.8 mL, 3.6 mol), and concentrated hydrochloric acid (14.1 mL, 464.1 mmol). The reaction was carried out at 95 °C with stirring for 16 hours. After completion of the reaction, the reaction solution was cooled to room temperature and the pH was adjusted to neutral. After filtration, the filtrate was concentrated and extracted with ethyl acetate. The organic phases were combined, dried with anhydrous magnesium sulfate, and the solvent was removed by rotary evaporation to afford 11.9 g of the title product 4-amino-2,6-dichloropyridine in 95.1% yield.

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