Improvements in the Manufacture of Chlorine Derivatives, of Toluene.
Year: 1896

page_text: Date of Application, 24th Dec., 1896
Complete Specification Left, 24th Sept., 1897-Accepted, 16th Oct., 1897
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Chlorine Derivatives, of
Toluene.
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU
RHONE, anciennement GILLIARD, P. MONNET ET CARTIER, of Lyons, France,
Manufacturers.
I, GEORGE. BELOE ELLIS of the Firm of J. C. Mewburn and Ellis of 55 and
56 Chancery Lane in the County of London, Chartered Patent Agents, do hereby
declare the nature of this invention to be as follows:-
This invention relates to the manufacture of ortho- and para-chlor-benzylidene
chlorides and other chlorine derivatives of tolueue from ortho- and para-toluene-
sulphochlorides.
The chlorine derivatives of toluene, and especially ortho- and para-chlor-benzyli-
dene chloride, are employed in the arts for the preparation of aromatic aldehydes
and acids and other complex compounds. Their preparation is generally effected by
indirect and expensive methods. For instance ortho-chlor-benzylidene chloride is at
present manufactured from ortho-toluidine, which is converted by the Sandmeyer
reaction into ortho-chlor-toluene. When this body is further heated with chlorine at
a higher temperature in the presence of phosphorus pentachloride, it yields a
mixture of various chlorine compounds, of which ortho-chlor-benzylidene chloride is
the chief.
T
Recent improvements however in the manufacture of toluene sulphochlorides, and
especially of ortho-toluene sulphochloride, from toluene by means of chlor-sulphonic
acid, has drawn attention to the sulpho-chlorides as possibly a cheaper and more
profitable source than toluidine for the preparation of chlorine derivatives of toluene,
and especially of ortho-chlor-benzylidene chloride.
In the Specification to British Letters Patent No. 6626 of 1885 Fahlberg states
that when the solid para-toluene-sniphochloride is mixed with carbon, moistened and
subjected to the action of superheated steam under pressure, it is decomposed into
tolueue, hydrochloric acid and sulphurous acid.
My foreign correspondents have discovered that when pure ortho- or para-toluene-
sulphochloride is distilled alone at ordinary pressure it is decomposed with formation
of sulphurous acid, and the respective ortho- or para-chlor-toluene. A part of the
sulphochloride is at the same time further decomposed.
My foreign correspondents have further discovered that the, sulphurous acid may
be split off more easily and without any more fundamental decomposition, and at a
lower temperature (about 150° C. instead of 200° C.) by conducting a stream of dry
chlorine gas through the heated toluene-sulphochloride. By this method it is
possible to obtain a good yield of ortho- or para-chlor-benzylidene chloride from
ortho- or para-toluene-sulpho-chloride respectively in one operation.
The following example will show how the invention is to be carried out with regard
to the production of ortho-chlor-benzylidene-chlorides from ortho toluene-sulpho-
chlorides.

page_text: The ortho-toluene-sulpho-chloride is heated to 150° C. and a stream of chlorine
gas is conducted into the hot liquor in the course of which operation the temperature
rises to between 150° C. and 200° C. At first the mass decreases slightly in weight,
as sulphurous acid is evolved, but it soon ceases to lose in weight, and ultimately
regains its original weight, as the loss of sulphurous acid is compensated for by
absorption of chlorine, the two reactions going on simultaneously.
The para-toluene-sulphochloride may be treated in a similar manner to obtain the
corresponding chlor-benzylidene-chloride.
When the reaction is finished, which is the case when two molecular proportions
of chlorine have been absorbed by the mass, the product is distilled. In the case of
the ortho product this may be done at ordinary pressure, when ortho-chlor-benzyli-
dene chloride passes over between 225° and 235° C.; the distillate when treated
with 100 per cent. sulphuric acid yields very pure ortho-chlor-benzoic aldehyde. The
para-chlor-benzylidene chloride is preferably distilled under reduced pressure, and
the fraction distilling between 155° C. and 165° C. at 60 mm. pressure collected.
On treatment with sulphuric acid this product yields para-chlor-benzoic acid melting
at 236° C..
The chlorination proceeds more rapidly if a small quantity of phosphorus
pentachloride is added to the mass, and naturally more or less chlorinated products
may be obtained according to the quantity of chlorine employed.
Datadithia 04th day of Decembar 1908
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.
Improvements in the Manufacture of Chlorine Derivatives of
Toluene,
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE,
anciennement GILLIARD, P. MONNET CARTIER, of Lyons, France,
Manufacturers.
I, GEORGE BELOE ELLIS of the Firm of J. C. Mewburn and Ellis of 55 and
56 Chancery Lane in the County of London, Chartered Patent Agents, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to the manufacture of ortho- and para-chlor-benzylidene
chlorides (ortho- and para-chlor-benzal chlorides, CHCI CHCI) and other chlorine
derivatives of toluene from ortho- and para-toluene-sulpho-chlorides.
The chlorine derivatives of toluene, and especially ortho- and para-chlor-benzylidene
chloride, are employed in the arts for the preparation of aromatic aldehydes and acids
and other complex compounds. Their preparation is generally effected by indirect
and expensive methods. For instance ortho-chlor-benzylidene chloride is at present
manufactured from ortho-toluidine, which is converted by the Sandmeyer reaction
into ortho-chlor-toluene. When this body is further heated with chlorine at a
higher temperature in the presence of phosphorus pentachloride, it yields a mixture
of various.chlorine compounds, of which ortho-chlor-benzylidene chloride is the chief.
Recent improvements however in the manufacture of toluene sulphochlorides, and
especially of ortho-toluene sulphochloride, from toluene by means of chlor-sulphonic

page_text: acid, has drawn attention to the sulpho-chlorides as possibly a cheaper and more
profitable source than tolnidine for the preparation of chlorine derivatives of toluene
and especially of ortho-chlor-benzylidene chloride.
In the Specification of British Letters Patent No. 6626 of 1885 Fahlberg states
that when the solid para-toluene-sulphochloride is nixed with carbon, moistened and
subjected to the action of superheated steam under pressure, it is decomposed into
toluene, hydrochloric acid and sulphurous acid.
My foreign correspondents have discovered that when pure ortho- or para-toluene-
sulphochloride is distilled alone at ordinary pressure it is decomposed with formation
of sulphurons acid and the respective ortho- or para-chlor-toluene. A part of the
sulphochloride is at the same time further decomposed.
My foreign correspondents have further discovered that the sulphurous acid may
be split off more easily and without any more fundamental decomposition, and at a
lower temperature (about 150° C. instead of 250° C.) by conducting a stream of dry
chlorine gas through the heated toluene-sulphochloride. By this method it is
possible to obtain a good yield of ortho- or para-chlor-benzylidene chloride from
ortho- or para-toluene-sulpho-chloride respectively in one operation.
The following sample will show how the invention is to be carried out with regard
to the production of ortho-chlor-benzylidene-chloride (ortho-chlor-benzal chloride,
CHCI CHCI) from ortho-toluene-sulpho-chloride.
The ortho-toluene-sulpho-chloride is heated to 150° C. and a stream of dry chlorine
gas is conducted into the hot liquor which is maintained during the operation at a
temperature between 150° C. and 200° C. At first the mass decreases slightly in
weight, as sulphurous acid is evolved, but it soon ceases to lose in weight, and
ultimately regains its original weight, as the loss of sulphurous acid is compensated
for by absorption of chlorine, the two reactions going on simultaneously.
The para-toluene-sulphochloride may be treated in a similar manner to obtain the
corresponding chlor-benzylidene-chloride, but in this case it is more difficult to
regulate the reaction, and a large quantity of para-chlor-benzotrichloride is always
formed. When the reaction is finished, which is the case when two molecular
proportions of chlorine have been absorbed by the mass, the product is distilled. In
the case of the ortho product this may be done at ordinary pressure, when ortho-
chlor-benzylidene chloride passes over between 225° and 235° C.; the distillate
when treated with 100 per cent. sulphuric acid yields very pure, ortho-chlor-benzoic
aldehyde. The product of the treatment of para-toluene-sulphochloride is preferably
distilled under reduced pressure, and the fraction, distilling between 155° C.
and 165° C. at.60 mm. pressure, collected. On treatment with sulphuric acid this
product yields para-chlor-benzoic acid melting at 236° C.
The chlorination proceeds more rapidly if a small quantity of phosphorus penta-
chloride is added to the mass, and naturally more or less chlorinated products may
be obtained according to the quantity of chlorine employed.
Having now particularly described and ascertained the nature of the said invention
as communicated to me, and in what manner the same is to be performed;
I declare that what I claim is :-
1. The preparation of chlorine derivatives of toluene from the ortho- or para-
toluene-sulphochloride, by treating ortho- or para-toluene-sulpho-chloride, when
heated, with a current of dry chlorine gas, substantially as described.
2. The manufacture of ortho-chlor-benzylidene-chloride (ortho-chlor-benzal chloride
CH.CI CHCI) by passing into ortho-toluene-sulphochloride heated to 150° C. a
stream of dry chlorine gas, and maintaining the reaction at 150° to 200° C. until two
molecular proportions of chlorine have been absorbed, distilling the resulting mass
and collecting the distillate which passes over between 225° and 235° C., substantially
as described.
3. The manufacture of para-chlor-benzylidene chloride (para-chlor-benzal chloride
CHCI CHCI) and of para-chlor-benzochloride from para-toluene sulphochloride
by passing a stream of dry chlorine gas into para-toluene sulphochloride heated

page_text: to a temperature between 1500 and 200° C., and fractionally distilling the resulting
mass preferably under reduced pressure, substantially as described.
. Dated this 24th day of September 1897.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.