I Âcenaphthenequinone has been mono- brominated
and the product shown to be 4- bromo- acenaphthenequihone,
the direct bromination described being the best method
of preparing the latter compound. Various derivatives,
have been prepared, including 4- bromo- naphthalic
anhydride by oxidation with hydrogen peroxide in
alkaline solution.
TI The bromination of naphthalic anhydride has
been studied. The product obtained by the action of
bromine in a mixture of oleum and concentrated sulphuric acid has been shown to be 3- bromo- naphthalic
anhydride and not the 4- bromo- derivative as has
hitherto been assumed. It has been shown that
3- sulpho -naphthalic anhydride is not formed as an
intermediate stage in this reaction. The same compound was obtained by the action of bromine on
naphthalic anhydride in a sealed tube, and an improved
method of preparing it, namely by the action of
bromine in concentrated nitric acid, is described.
Proof of the constitution of the 3- bromo-naphthalic
anhydride consisted in a direct comparison with a
specimen prepared from 3- nitro-naphthalic acid by
reduction, diazotisation and treatment with cuprous
bromide. Further confirmation follows from the work
on the mercuration summarised below.
On the other hand, by the bromination of naphthalic
acid (as alkali salt) by bromine in presence of
alkali hypobromite, 4- bromo- naphthalic anhydride has
been prepared.
Derivatives of the- two mono -bromo- naphthalic
anhydrides have been prepared for purposes of comparison.
III Mercurations of 3- bromo- and 4- bromo- naphthalic
anhydride have been carried out. From the mixture
obtained by hydrolysis of the mercuration product
from the former, the hitherto unknown 3- bromo -naphthoic
acid was obtained, its constitution being proved by
direct comparison with a specimen prepared from 3-
nitro-naphthoic acid by reduction, diazotisation and
treatment with cuprous bromide. Hydrolysis of the
mercuration product from 4- bromo- naphthalic anhydride
gave a mixture from which 5- bromo -naphthoic acid was
isolated. This compound is already described in the
literature, being prepared by the bromination of
naphthoic acid. Identity of specimens from the two
sources was proved.
IV (a) The introduction of more than one atom of
143.
bromine into acenaphthenequinone and naphthalic anhydride respectively has been studied. In each case a
tribromo- derivative has been obtained, the orientation
of the bromine atoms being the same, since the tribromo- acenaphthenequinone on oxidation gave a tribromo- naphthalic anhydride identical with that obtained
directly from naphthalic anhydride. It has not yet
been possible decisively to prove the positions of the
bromine atoms.
(b) The mono- nitration of 4- nitro -naphthalic
anhydride (obtained by oxidation of 4- nitro -acenaphthene)
has been shown to give 4:5- dinitro- naphthalic anhydride.
On the other hand when 4- bromo- naphthalic anhydride is nitrated it yields 3- nitro -4- bromo- naphthalic
anhydride. To prove the constitution of the latter
compound it was synthesised in a manner showing its
constitution, being prepared by the oxidation of
3- nitro -4- bromo- acenaphthene, which was obtained from
the already known 3- nitro -4- amino -acenaphthene by
diazotisation and treatment with cuprdus bromide.
V The condensation of naphthalic anhydride and
its substituted derivatives with o- phenylenediamine
has been shown to take place in glacial acetic acid
with loss of two molecules of water to give 1:8-
naphthoylene- l:2- benziminazole and its derivatives.
When the naphthalic anhydride was of a symmetrical
structure, a well- defined derivative was obtained,
but unsymmetrical anhydrides gave mixtures of compounds which could not be separated.
VI (a) A study has been made of methods for the
preparation of acenaphthenone, some new methods being
described. The best preparative method was found to
be the reduction of acenaphthenequinone oxime, which
can be prepared directly from acenaphthene. Reduction
of acenaphthenequinone phenylhydrazone also provides
a serviceable method.
In connection with this work the preparation of
acenaphthenequinone anil, Wolff's reaction on ace - naphthenequinone semicarbazone, the action of ammonia
on l:l- dichloro- acenaphthenone and that of methylamine
on acenaphthenequinone have been investigated. The
imide and methylimide expected in the last two cases
respectively were not obtained, condensation between
two molecules taking place to form azine derivatives.
(b) Acenaphthenone on direct bromination yields
first 1- bromo- acenaphthenone and on further bromination
l:1- dibromo- acenaphthenone. Attempts to evolve
indirect preparative methods for bromo- derivatives of
acenaphthenone substituted in the nucleus were not
successful.
(o) By nitration of acenaphthenone a compound has
been obtained which on oxidation yields 4- nitro-
naphthalic anhydride. definite conclusion with
regard to its constitution has not however been
reached.
VII A new method is described for the preparation
of biacenaphthylidenedione, this compound resulting
quantitatively by the action of sodium sulphide on
1:1- dichloro- acena-phthenone in alcoholic solution.
By reduction of biacenaphthylidenedione with sodium
hydrosulphite in alkaline solution, or with iron
filings and glacial acetic acid, a new compound,
which also results from the reduction of acenaphthenequinone with hydriodic acid and red phosphorus at
160-170° has been obtained. It has been proved to
be l:1`- diacenaphthenonyl by synthesis of the latter
by a method showing its constitution, namely by the
action of copper bronze in boiling xylene on 1-bromoacenaphthenone.
