2,6-Dichloro-3-nitropyridine is a starting compound for the synthesis of a sulfide analog of Flupirtine with KV7.2/3 channel opening activity. 2,6-Dichloro-3-nitropyridine can be used in pain research.
Nitropyridine nucleus played a pivotal role in the development of different medicinal agents and in the field of agrochemicals. It is seen from the current literature that pyridine derivatives have been developed and used as insecticidal agents. Nitrated pyridines and their derivatives are important intermediates in synthesis of heterocyclic compounds in dyes and pharmaceutical products. Fused heterocycles containing nitropyridine systems have been associated with several biological and medicinal activities including antiolytic, antiviral and anti-inflammatory profiles.
General procedure for the synthesis of 2,6-dichloro-3-nitropyridine from 2,6-dichloropyridine: 80 mL of concentrated sulfuric acid was added to a 150 mL three-necked flask with stirring at room temperature, and 7.4 g (0.05 mol) of 2,6-dichloropyridine (IV) was slowly added, followed by the slow addition of 10.1 g (0.1 mol) of potassium nitrate. After the addition was completed, stirring was continued for 30 minutes, then the temperature was slowly increased to 120°C and the reaction was maintained at this temperature for 10 hours. Upon completion of the reaction, the reaction mixture was cooled to room temperature and poured into crushed ice with stirring. The precipitated white solid precipitate was washed to neutrality with ice water, immediately subjected to diafiltration, and dried to give 7.75 g of white solid 2,6-dichloro-3-nitropyridine (V) in 80% yield and melting point of 61-63 °C.
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