Supported Bismuth(III)Nitrate on Silica Sulfuric Acid as Useful Reagent for Nitration of Aromatic Compounds under Solvent-Free Conditions*

摘要

A number of aromatic compounds were nitrated to the corresponding nitroaromatic derivatives with the use of supported bismuth(III)nitrate on silica sulfuric acid under solvent-free conditions.Conventional methods for the nitration of aromatic compounds utilize a mixture of nitric and sulfuric acids or nitronium tetrafluoroborate [1].In the latter case,the nitration is accompanied by liberation of HF and BF_4 [1].Nitro derivatives necessary for the preparation of azido-substituted aromatic compounds as photo-affinity ligands [2] were obtained by usual nitric-sulfuric acid and nitronium tetrafluoroborate methods [3].In the recent time,reactions occurring under solvent-free conditions attract much attention [4-6].The main advantages of such methods,as compared to classical procedures,are cleaner reactions,reduced reaction time,and easy isolation of the products.