A process for producing pyridine or picoline compounds, comprises the steps: a) reacting a reactant feedstream comprising ammonia and at least one C1-5 carbonyl reactant in the presence of a molecular sieve catalyst to produce a primary product stream comprising pyridine or picoline products and polyalkylpyridines; b) isolating from the primary product stream a product fraction comprising pyridine or picoline products, and a polyalkylpyridine fraction comprising polyalkylpyridines; and c) contacting the polyalkylpyridine fraction with a molecular sieve catalyst to produce a secondary product stream comprising pyridine or picoline products, preferably by recycling the polyalkylpyridine fraction back to step (a).