Nitration of Aromatic Compounds on Silica Sulfuric Acid

Nitration of organic compounds has long been a very active and rewarding area of research and is the subject of a large body of literature.1 Also nitro-aromatics compounds are extensively utilised and act as chemical feedstocks for a wide range of useful materials such as dyes, pharma-ceuticals, perfumes, and plastics.2 Therefore, the nitration of aromatic rings has received considerable attention of late, due to unsolved problems pertaining to regioselectivity, overnitration and competitive oxidation of substrates.3 Nitration of phenol taken as a special case has been studied by various nitrating agents under different conditions.4 The nitration of benzene and toluene is one of the most important routs to substituted aromatics in the production of chemical intermediates.5 The industrial nitration of toluene is performed by means of mixed acid, a mixture of nitric acid,