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122 CHEMISTRY AND TECHNOLOGY OF EXPLOSIVES

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Nitrous esters can react with alkyl peroxides to yield alkyl nitrates [163,221]

(see also Vol. II).

ORGANIC COMPOUNDS AS NITRATING AGENTS

NITRIC ACID ESTERS

Nitric acid esters can be used as nitrating agents in the presence of sulphuric

acid and in some cases in a strongly alkaline medium.

Nitric esters in mixtures with sulphuric acid. Raudnitz [171] was the first to

draw attention to the nitrating properties of solutions of ethyl nitrate in sul-

phuric acid. Later in 1941, Titov [34] expressed the view that such a solution

contains the nitronium ion, and L. P. Kuhn (p. 15) proved this by cryometric

measurements. A solution of ethyl nitrate in sulphuric acid has been used for nitrat-

ing aromatic compounds.

The application of other nitric acid esters is also possible. Thus, Bucherer [172]

suggested the use of a solution of nitrocellulose in sulphuric acid to nitrate benzene

to nitrobenzene, while Plaiek and Ropuszyliski [173] suggested solutions of nitric

esters of polyalcohols, such as nitroglycerine, nitromannite, pentaerythritol tetra-

nitrate, for nitration of aromatic hydrocarbons. Ropuszyliski [174] recently in-

vestigated the action of a solution of nitroglycerine in sulphuric acid more fully

and inferred that decomposition of nitroglycerine by sulphuric acid to form a nitro-

nium ion was probably taking place by stages:

C 3 H 5 (ONO 2 ) 3 + H 2 SO 4 <-> C 3 H 5 (ONO 2 ) 3 H+ + HSO 4 - (77)

C 3 H 5 (ONO 2 ) 3 H

+ <-> C

3 H 5 (OH)(ONO 2 ) 2 + NO 2

+ (77a)

With an excess of sulphuric acid, glycerine dinitrate was decomposed to give fur-

ther nitronium ions, etc. Finally a double ester nitric and sulphuric of glycerol was
formed :

C 3 H 5 (OH) 2 (ONO 2 ) + H 2 SO 4 -> C 3 H 5 (OH)(ONO 2 )(OSO 3 H) + H 2 O (77b)

Nitric esters in alkaline medium. In some instances compounds containing
an active methylene group can be nitrated with nitric esters in the presence of