110 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVESBachman and Hokama found that benzene was nitrated by the complex in
5-6% yield, whereas nitrotoluene formed gum. If, however, toluene is nitrated
in nitroethane, then 56% of o- nitrotoluene, 1% of p- nitrotoluene and 3% of
2,4-dinitrotoluene are obtained. o- Nitrotoluene can be nitrated to 2,4-dinitro-
toluene by the complex in 40% yield.
The above mentioned authors have diazotized aniline with the complex and
obtained fluorobenzene.
Recently Tedder [120, 121] has shown that by acting directly with the complex
on aromatic hydrocarbons, diazonium salts can be obtained.NITRIC ACID IN THE PRESENCE OF MERCURIC NITRATE
The catalytic action of mercuric nitrate in the nitration of anthraquinone with
nitric acid was observed in 1906 by Holdermann [122]. Soon after that, Wolffen-
stein and Boters [123] observed the specific influence that mercuric nitrate exer-
cised on the formation of the products of nitration of benzene. They showed that
at a certain concentration of nitric acid, mostly nitrophenols were formed (“oxy-
nitration” reaction).
In his later studies Wolffenstein found that the hydroxyl group could be intro-
duced in this way into the aromatic ring, not only in the case of benzene but alsowith its derivatives as well. For example, benzoic acid yielded trinitro-m-hydroxy-
benzoic acid in the presence of mercuric nitrate:
Broders [124] isolated from the nitration products an organomercuric compound
to which he ascribed the following formula:
On this basis Desvergnes [125] suggested a mechanism for nitration in the
presence of mercuric nitrate that assumes the formation of diphenylmercury as
an intermediate product.
Nitrobenzene is also formed besides nitrophenols and this has been explained
by Desvergnes according to the following series of reaction: