AROMATIC NITRO COMPOUNDS 197(15)(R are alkyls)The reactivity of the nitro group is also manifested by the ease of its reduc-
tion. Thanks to this, aromatic compounds (e.g. nitrobenzene) can be used as
oxidizing agents in the well known Skraup reaction.
INFLUENCE OF NITRO GROUPS ON REACTIVITY OF HYDROGEN
ATOMS AND SUBSTITUENTS. NUCLEOPHILIC REACTIONSThe fact that the nitro group is a meta-orienting one can be explained by the
induction effect, caused by its electron attracting properties (I):
In practice, ortho and para substitutions also occur to a lesser extent along
with the meta substitution in relation to the nitro group. Some deviations from
the rule of substitution in the meta position are also encountered.
The nitro group has a considerable influence on the properties of the whole
molecule of an aromatic compound. For example, owing to the presence of the
nitro group, nitrobenzene does not take part in the Friedel-Crafts reaction.
The reactivity of a chlorine atom, brought about by the presence of a nitro group
in the ortho or para position, may be represented by a diagram based on the in-
duction effect (Ia).