OZONE-MEDIATED NITRATION OF ALKYLBENZENES AND RELATED-COMPOUNDS WITH NITROGEN-DIOXIDE

In the presence of ozone, nitrogen dioxide exhibits a strong nitrating ability for alkylbenzenes at low temperatures, converting them into t he corresponding nitro derivatives in high yield. The addition of a pr otonic acid as catalyst enhances considerably the ability of this nitr ating system and leads to a good yield of polynitro compounds. The rea ction is clean and proceeds rapidly without any accompanying side-chai n substitution or aryl-aryl coupling. It shows no kinetic dependence o n the concentration of substrates and. as far as can be judged from re lative reactivities and isomer distributions of products, it gives the appearance of being an electrophilic aromatic process. A possible rol e for nitrogen trioxide has been suggested as the initial electrophili c agent for the nitration of alkylbenzenes.