Nicotinic acid is a naturally occurring pyridine carboxylic acid, contained in vitamin PP, an essential nutrient for humans and animals, and used as an antipelagic agent. Nicotinic acid can be made from tryptophan by plants and animals but is usually not completely bioavailable. Industrially, nicotinic acid is produced mainly by oxidation of 5-ethyl-2-methylpyridine with nitric acid. One of the by-products of the process is nitrous oxide, a gas that is difficult to recycle and manage, with a greenhouse effect 300 times stronger than CO₂. A new technology for the industrial production of nicotinic acid is undoubtedly necessary to meet the needs of green chemistry and not burden the environment. We carried out a literature review on ecological methods to produce nicotinic acid from commercially available raw materials such as 3-methylpyridine and 5-ethyl-2-methylpyridine, especially focusing on those methods with potential industrial applications.

4-Hexyloxycarbonyl-, 4-dodecyloxycarbonyl- and 4-hexadecyloxycarbonyl-N-hydroxyphthalimides were synthesised using trimellitic anhydride chloride as the starting material. The obtained lipophilic derivatives of N-hydroxyphthalimide were applied as catalysts of the cumene oxidation reaction with oxygen performed in polar acetonitrile, in non-polar tert-butylbenzene and in the absence of a solvent. The courses of reactions catalysed by N-hydroxyphthalimide and its derivatives were compared.

The oxidations of cumene, 4-isopropylbiphenyl, 1-methoxy-4-(1-methylethyl)benzene, 2-isopropylnaphthalene, 2-methoxy-6-(1-methylethyl)naphthalene, 2,6-diisopropylnaphthalene and 4,4′-diisopropylbiphenyl to the corresponding hydroperoxides with oxygen, at 60 °C, in the presence of N-hydroxyphthalimide (NHPI) and AIBN have been performed. Process inhibition was observed at temperatures above 60 °C resulting in lower conversion. A favorable effect of electron-donating substituents (methoxy, phenyl) on the reaction rate were described. NHPI was separated from the cumene oxidation product and recycled 5 times. It has been demonstrated that oxygen can be replaced by air.