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2-Methylpyridine, or 2-picoline, is the compound described with formula C 6 H 7 N. 2-Picoline is a colorless liquid that has an unpleasant odor similar to pyridine. It is mainly used to make vinylpyridine and the agrichemical nitrapyrin .
2-Methylpyridine- and 4-methylpyridine are produced as a mixture from acetaldehyde and ammonia. 3-Methylpyridine and pyridine are produced from acrolein and ammonia. Acrolein and propionaldehyde react with ammonia affords mainly 3-methylpyridine. 5-Ethyl-2-methylpyridine is produced from paraldehyde and ammonia. [5]
3-Methylpyridine degrades more slowly than the other two isomers, likely due to the impact of resonance in the heterocyclic ring. Like most simple pyridine derivatives, the picolines contain more nitrogen than is needed for growth of microorganisms, and excess nitrogen is generally excreted to the environment as ammonium during the degradation ...
In 1989, 26,000 tonnes of pyridine was produced worldwide. Other major derivatives are 2-, 3-, 4-methylpyridines and 5-ethyl-2-methylpyridine. The combined scale of these alkylpyridines matches that of pyridine itself. [2] Among the largest 25 production sites for pyridine, eleven are located in Europe (as of 1999). [24]
4-Methylpyridine is both isolated from coal tar and is synthesized industrially. It forms via the reaction of acetaldehyde and ammonia in the presence of an oxide catalyst. The method also affords some 2-methylpyridine. 4-Methylpyridine is of little intrinsic value but is a precursor to other commercially significant species, often of medicinal ...
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