Pyridine, reactions with—continued aryls

Introduction of heteroatoms, e. g. N, S, or O, into hydrocarbon molecules adds substantial value, and new routes for such reactions are of continuous interest to the chemical industry. The two main classes of aromatic N-containing hydrocarbons are the arylamines and the aromatic N-heterocyclic compounds. The aryl-amines, which are required industrially, are manufactured by nitration of aromatics to nitroaromatics, followed by hydrogenation to arylamines [1,2]. Because of the lower demand for aromatic heterocycles than for arylamines, coal tar is still an important source of pyridine and methylpyridines (picolines). Increasing demand for aromatic heterocyclic compounds has led to processes in which aldehydes and ketones are condensed with NH3 to furnish pyridine and alkylated pyridines [3,4]. 

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