Nitrations with nitronium ions the general case

2 NITRATIONS WITH NITRONIUM IONS THE GENERAL CASE 6.2.1 Evidence from solvent effects 

Hughes, Ingold and Reed discussed the relative merits of the and e3 schemes as mechanisms for nitration by considering the properties of acetic acid, nitromethane, nitric acid and sulphuric acid as media for the reaction. The facts have already been discussed ( 2.2.3, 2.2.4, 2.3.2, 2.4.2, 2.4.3, 3-2). 

The process of nitration can be expressed in the following compressed form  

All of the reactions leading to the generation of the nitronium ion are summarized in a, processes reversing this generation in b, and all the processes involved in the attack by nitronium ion upon the aromatic and expulsion of the proton in c. 

In the cases of nitration in the organic solvents, the process a leads to the formation of two ions and a neutral molecule from two neutral 

The SE 3 mechanism does not satisfactorily account for the kinetic observations, as can be seen when the nature of the base (B) in nitrations is recalled it would most likely be a nitrate or bisulphate anion. 

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