Improvements in the Manufacture of Aldehydo-benzoic Acid and Intermediate Products.
Year: 1897

page_text: Date of Application, 23rd Apr., 1897
Complete Specification Left, 24th Jan., 1898-Accepted, 19th Mar., 1898
Improvements in the Manufacture of Aldehydo-benzoic Acid and
Intermediate Products.
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE,
anciennement Gilliard P. Monnet et Cartier, of Lyons, France, Manu-
facturers.
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 aldehydo-benzoic acid, which is the
simple aldehyde of ortho-phtalic acid. The invention includes certain intermediate
products obtained in the manufacture of aldehydo-benzoic acid in the manner
hereinafter described.
Whanauhall
which may be obtained by the oxidation of naphtalene or of naphtalene
derivatives with permanganate, is boiled with anilin, an insoluble body is formed
melting above 250° C., which is not a benzylidene derivative, nor can it be
converted into aldehydo-benzoic acid by any known method.
My correspondents have discovered that if ortho-oxalyl-benzoic acid is however
treated with anilin in aqueous solution, a novel product is formed of the probable
formula
which is very sensitive to reagents and may be converted into aldehydo-benzoic
acid. The product of the said reaction is only slightly soluble in water, melts
at 165° C. with evolution of gas and if melted becomes converted into the body
melting above 250° C.
Both the new anilin salt obtained by treating ortho-oxalyl-benzoic acid with
anilin in aqueous solution, and the free acid liberated from it, may be converted in
various ways into anilido-benzylidene-ortho-carboxylic acid

page_text: A certain quantity of this compound is formed by melting the anilin salt in vacuum,
when anilin distils off, leaving a residue, which contains besides the benzylidene-
carboxylic acid also considerable quantities of the above mentioned insoluble body
melting above 250° C.
A very good yield of the benzylidene-carboxylic acid is obtained if the anilin
salt formed by the treatment of ortho-oxalyl-benzoic acid with anilin in aqueous
solution, or its free acid, is boiled with a neutral solvent such as toluene or xylene.
The product thus obtained melts at 174° C. and is identical with the anilido-
benzylidene-ortho-carboxylic acid described by Racine; by simply boiling with
mineral acids it is converted into aldehydo-benzoic acid.
According to one way of carrying out the invention there may be used as raw
material the solution obtained by oxidation of naphtalene or naphtalene
derivatives with permanganate, after filtering off the manganese oxide and
acidulating with acetic acid. The solution always contains phtalic acid as well as
ortho-oxalyl-benzoic acid, but the phtalic acid can be easily removed as anilin salt
in the course of the following operation.
To the solution of ortho-oxalyl-benzoic acid are added three molecular
proportions of anilin with constant stirring, and the mixture warmed for half an
hour at 80° to 100° C. On cooling, the new anilin salt crystallizes out in yellowish
leaflets of great purity, whilst any phtalic acid remains in solution as anilin salt.
The new product is filtered off and dried.
The anilin salt thus obtained is suspended in five times the quantity of commercial
xylene, for instance, and heated to boiling for about an hour under a return
condenser. Gradually all goes into solution with evolution of carbon dioxide, and
after cooling the anilido-benzylidene-ortho-carboxylic acid crystallizes out. It is
filtered off, and when thus obtained melts at 174° C. without decomposition.
In order to convert it into aldehydo-benzoic acid, the anilido-benzylidene-ortho-
carboxylic acid is suspended in about ten times the quantity of 10 per cent.
hydrochloric or sulphuric acid and warmed upon the water bath. Solution rapidly
takes place, and after filtration the cold solution is extracted with ether. From the
ethereal extract aldehydo-benzoic acid may be obtained as will be well understood
in a very pure state, melting at 97° to 98° C.
Improvements in the Manufacture of Aldehydo-benzoic Acid and
Intermediate Products.
A communication from abroad by LA SOCIÉTÉ CHIMIQUE DES USINES DU RHÔNE,
anciennement Gilliard P. Monnet et Cartier, of Lyons, France, Manu-
facturers.
I, GEORGE BELOE ELLIS, of the Firm of J. C. Mewburn & Ellis, of 55 and 56,
Chancery Lane, in the County of London, Chartered Patent Agents, do hereby
declare the nature of the said 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 aldehydo-benzoic acid, which is the

page_text: simple aldehyde of ortho-phtalic acid. The invention includes certain intermediate
products obtained in the manufacture of aldehydo-benzoic acid in the manner
hereinafter described.
When onthe ovalul benzoic acid
which may be obtained by the oxidation of naphthalene or of naphthalene
derivatives with permanganate, is boiled with anilin, an insoluble body is formed
melting above 250° C. which is not a benzylidene derivative, nor can it be converted
into aldehydo-benzoic acid by any known method.
My correspondents have discovered that if ortho-oxalyl-benzoic acid is however
treated with anilin in aqueous solution, a novel product is formed of the probable
which is very sensitive to reagents and may be converted into aldehydo-benzoic
acid. The product of the said reaction is only slightly soluble in water, melts at
165° C. with evolution of gas, and if melted becomes converted into the body
melting above 250° C.
Both the new anilin salt obtained by treating ortho-oxalyl-benzoic acid
with anilin in aqueous solution, and the free acid liberated from it by the addition
of dilute mineral acids as will be well understood, may be converted in various
ways into anilido-benzylidene-ortho-carboxylic acid
A certain quantity of this compound is formed by melting the aniline salt in
vacuum, when anilin distils off, leaving a residue, which contains besides the
benzylidene-carboxylic acid also considerable quantities of the above mentioned
insoluble body melting above 250° C.
A very good yield of the benzylidene-carboxylic acid is obtained if the anilin
salt formed by the treatment of ortho-oxalyl-benzoic acid with anilin in aqueous
solution, or its free acid, is boiled with a neutral solvent such as toluene or xylene.
The product thus obtained melts at 174° C. and is identical with the anilido-
benzylidene-ortho-carboxylic acid described by Racine; by simply boiling with
mineral acids it is converted into aldehydo-benzoic acid.
According to one way of carrying out the invention, there may be used as raw
material the solution obtained by oxidation of naphthalene or naphthalene
derivatives with permanganate, after filtering off the manganese oxide and acidulating
with acetic acid. The solution always contains phtalic acid as well as ortho-oxalyl-
benzoic acid, but the phtalic acid can be easily removed as anilin salt in the course
of the following operation.
To the solution of ortho-oxalyl-benzoic acid are added three molecular
proportions of anilin with constant stirring, and the mixture warmed for
half an hour at 80° C. to 100° C. On cooling, the new aniline salt crystallizes out
in yellowish leaflets of great purity, whilst any phtalic acid remains in solution as
anilin salt. The new product is filtered off and dried.

page_text: The anilin salt thus obtained is suspended in five times the quantity of
commercial xylene, or in ten times the quantity of toluene, for instance, and
heated to boiling for about an hour or more under a return condenser. Gradually
all goes into solution with evolution of carbon dioxide, and after cooling, the
anilido-benzylidene-ortho-carboxylic acid crystallizes out. It is filtered off, and
when thus obtained-melts-at-about 174° C. without decomposition.
In order to convert it into aldehydo-benzoic acid, the anilido-benzylidene-
ortho-carboxylic acid is suspended in about 10 times the quantity of 10 per cent.
hydrochloric or sulphuric acid, and warmed upon the water bath. Solution rapidly
takes place, and after filtration, the cold solution is extracted with ether. From the
ethereal extract aldehydo-benzoic acid may be obtained as will be well understood in
a very pure state, melting at 97° to 98° C.
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 process of manufacturing aldehydo-benzoic acid from ortho-oxalyl-
benzoic acid, which consists in treating ortho-oxalyl-benzoic acid with anilin in
aqueous solution, converting the product into anilido-benzylidene-ortho-carboxylic
acid by dissolving it in a boiling neutral solvent such as toluene or xylene, and
hydrolysing the anilido-benzylidene-ortho-carboxylic acid by means of dilute acids,
substantially as described.
2. The process of obtaining a new anilin salt from ortho-oxalyl benzoic acid,
consisting in heating an aqueous solution of ortho-oxalyl-benzoic acid with three
molecular proportions of anilin, and crystallizing out, substantially as described.
3. The process of separating phtalic acid and ortho-oxalyl-benzoic acid in a
mixture of the oxidation products of naphthalene or its derivatives, by treating
the aqueous solution with anilin, whereby the ortho-oxalyl-benzoic acid is obtained
as the anilin salt of a new acid, substantially as described.
4. The process of converting the anilin salt formed by the treatment of ortho-
oxalyl-benzoic acid with anilin in aqueous solution into anilido-benzylidene-ortho-
carboxylic acid, by boiling the anilin salt or its free acid in a neutral solvent, such
as toluene or xylene, substantially as described.
5. As new products, the anilin salt obtained by heating an aqueous solution of
ortho-oxalyl-benzoic acid with three molecular proportions of anilin, and the free
acid thereof, substantially as described.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents.