Zeolite-assisted regioselective mononitration of naphthalene with nitrogen dioxide/molecular oxygen

Article abstract of DOI:10.1007/s11164-012-0827-z

The nitration process using nitrogen dioxide and oxygen instead of the classical nitric acid-sulfuric acid system appears to be attractive and promising in the selective preparation of nitro compounds. The ratio of 1-nitronaphthalene isomer to 2-nitronaphthalene can reach 11 in a moderate yield of 60 % when the reaction is carried out in acetonitrile with 5.0 mmol naphthalene, 10 mmol nitrogen dioxide, and 0.13 g HZSM-5 under molecular oxygen atmosphere at -15 C. The isomeric distribution of the product nitro-naphthalene was found to be superior to traditional methods. The zeolite could be easily regenerated and recycled and reused by simple work-up to give results similar to those obtained with the fresh catalyst.