An examination of the formation of the aromatic
iodo- chlorides has been carried out. Difficulty was
experienced in the isolation of the dichlorides of
certain diortho -substituted iodo -compounds. Further,
quantitative experiments have shown that this difficulty
is due, in some cases, to the instability of the dichloride
and to the appearance of side reactions.
Therefore the quantitative results cannot be taken as
being fundamental until experiments have been carried
out taking all these factors into consideration. The
quantitative results have shown, however, that no
¿eneral hindrance to the reaction has been encountered.
From scale diagrams of diortho-substituted iodobenzene
molecules this is to be expected. Only in two cases -
with the compounds 4.6- dibromo -2- nitro -iodobenzene and
4- iodo -3 :5- dinitrotoluene - has an appreciable retardation
of the reaction occurred. It is not certain
whether this is due solely to steric causes.
No difference in reactivity of substituted
a- and i3- iodonaphthalenes has been observed.
The dichlorides of ¡3- iodonaphthalenes have
proved to be very unstable. It was shown, in the case
of 1;6- dibromo- t3- iodonaphthalene, that decomposition is
accompanied by nuclear chlorination.
One new iodine derivative in the benzene
series and two in the naphthalene series have been
isolated. Several hitherto unknown dichlorides have
been described.
In the course of a brief examination it has
been shown that, whereas a- substituted aceto -¡3-
naphthalides are easily hydrolysed using alcoholid
hydrochloric acid, 3- substituted aceto -a- naphthalides
are resistant to this reagent.
Finally, condensation experiments have been
carried out with certain substituted thiobenzoic acids.
The method adopted for the preparation of the unknown
o- chloro- and o- bromo- thiobenzoic acids is suggested
as a general method for the preparation of mono -
substituted" thio- acids. More vigorous methods were
found necessary for the preparation of the new 2:4:6 -
tribromo- thiobenzoic acid. In the course of this
part of the research two new substituted dibenzoyl
disulphides and several new substituted benzanilides
were isolated. New lines for future research have
been suggested
