NEW SWEET COMPOUND AND PROCESS OF MANUFACTURING THE SAME
Year: 1885

page_text: This Print is in accordance with the Original Specification as it stands after
Amendment (under Section 18 of the Patents, &c., Act, 1883), as allowed
by the decision of the Law Officer of the 7th day of August 1896.
I, JAMES YATE JOHNSON, of 47 Lincolns Inn Fields in the County of Middlesex,
Gentleman do hereby declare the nature of the said invention for a "NEW SWEET
COMPOUND AND PROCESS OF MANUFACTURING THE SAME," a communication to me
from abroad by Constantin Fahlberg of New York, United States of Amerika, D.P.,
and Adolph List of Leipsic, Kingdom of Saxony, German Empire, Gentleman, and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
The present invention relates to a new sweet compound and process of manu-
facturing the same. This compound, which is scientifically termed "Anhydro
Ortho-sulphamine-benzoic acid or benzoic-sulphinide, contains the elements carbon,
hydrogen, oxygen, sulphur, and nitrogen, and possesses a similar taste as saccharose
or cane-sugar, but by far sweeter so that it may be employed as an advantageous
substitute for sugar in all cases where the latter would be too expensive, for
instance, in sweetening glucose, grape- or starch-sugar, and in other cases where
cane-sugar is used for sweetening and preserving. A very diluted solution thereof
tastes like a saturated solution of cane-sugar. The inventors call this new com-
pound "Saccharine."
The high antiseptic properties of saccharine will further recommend it for many
purposes in the arts and medicine. Owing to the fact that "saccharinė" cannot
be classed under the heading of nourishments like sugar and similar carbo-
hydrates, it may be used for many medical purposes where cane-sugar is excluded

page_text: from the diet of certain patients, as in cases. of "diabetes mellitus" and other
diseases.
Saccharine is difficultly soluble in cold water, it is more soluble in warm or hot
water and can easily be obtained from such solutions in crystalline form. Alcohol
and ether dissolve it readily.
It crystallizes in thick, short prisms, in all probability belonging to the monoclinic
system. The crystals, however, are small-and-imperfectly formed. It fuses at
about 200° centigr. under partial decomposition.
In an aqueous solution saccharine readily forms salt-like compounds with
the alkalies, alkaline earths or metallic oxydes in a similar manner as cane-sugar; 1
these salts possess the same pleasant and sweet taste as pure saccharine. All salts
of saccharine crystallize with difficulty; those of the alkalies yield on evaporation
a syrup-like mass, but do not crystallize even after standing a length of time.
Under certain conditions saccharine forms with the residues of the hydro-carbons,
such as methyl, ethyl, propyl, &c., compounds belonging to the class termed
"esters," and which possess the same sweetness as saccharine itself. All compounds
are innocuous to the human system. Saccharine being a derivative of benzoic acid,
does not ferment like sugar and other carbo-hydrates.
C
Having so far described the properties and advantages of the new compound,
I shall now proceed to set forth. the manner of its preparation.
Saccharine or Anhydro-Ortho-sulphamine-benzoic acid or benzoic sulphinide is
produced from coal-tar and other analogous products, in particular from such as
contain a considerable amount of benzene, toluene, &c. Although for economical
reasons toluene (C, H, CH) is generally preferred, other substitution-products of
benzene, such as yield on oxydation, or which contain without previous oxydation,
benzoic acid, may be employed.
FIRST METHOD.
In
Operation I. The first step consists in transforming the toluene into the two
isomeric toluene-monosulfonic acids. For this purpose, the toluene may be treated
with fuming sulphuric acid in cold state, or it is heated with hydrated sulphuric
acid of 66° Be to a temperature not rising above the boiling-point of water.
applying hydrated sulphuric acid, the reaction comes off more smoothly than with
fuming acid and without any boiling over. The sulphuric acid is preferably made
to act upon toluene in closed vessels rotating on horizontal axles.
Operation II. After the last traces of toluene have disappeared, the contents of
the vessel are run into wooden tanks partly filled with cold water, and mixed
therein with chalk (carbonate of lime Ca CO), in order to neutralize the excess of
sulphuric acid present and to obtain the toluene-monosulphonic acids formed as
sulphonates of lime. The neutralized mass is filtered through a filter-press to
separate therefrom the precipitated sulphate of lime. A certain amount of the
toluene-monosulphonates of calcium always persistently adheres to the sulphate of
lime remaining in the filter-press and must be separated by lixivation with hot
water. The lixivating liquor is then added to the first liquor and worked together
with the same.
Operation III. As the presence of lime-salts present certain inconveniences for
the following operations, the inventors prefer to convert the whole amount of
lime-salts contained in the liquors of the previous operation, into alkali-salts.
This may be effected with any of the known carbonates of the alkalies. Preferably
carbonate of sodium is used, so that the salts obtained will be toluene-mono-
sulphonates of sodium.
The sodium-carbonate is applied in concentrated solution
and as often as any precipitation of lime-carbonate will yet occur.
The carbonate of lime precipitated out is removed from the liquid by means of
a filter-press, and used again in operation H in place of ordinary chalk. This
quantity of lime-carbonate would be sufficient for a continuous preparation of
calcium-toluene-monosulphonates, were it not that in operation I an
excess 01

page_text: of chalk.
Operation IV. The resulting solution of the sodium-toluene-monosulphonates
is evaporated, either in an open or a vacuum pan, to such an extent as that a
portion taken therefrom will solidify after a short exposition to the air. The
contents of the pan are then ran into small moulds made of iron or wood, to cool
down and solidify. After a few hours the lumps formed are taken out of the
moulds and chipped into pieces or otherwise reduced by hand or machinery, and
thereupon placed into a drying room. Finally the salts are passed through a
suitable apparatus heated by steam so as to ensure their complete desiccation.
.
Operation V. When the said salts are completely freed of water, they are
transformed into the, corresponding toluene-sulphochlorides. For this end, they
are thoroughly mixed with phosphorus-pentachloride in an apparatus especially
constructed for this purpose. The phosphorus-pentachloride should be as dry as
possible. The mixture is then brought into iron vessels lined with lead and
transformed into the two toluene-sulphochlorides, i.e. the ortho-toluene-sulpho-
chloride and the para-toluene-sulphochloride. The former is liquid, and the latter
is solid. Of these two sulphochlorides the liquid one only is adapted for
producing saccharine. Instead of directly applying pentachloride of phosphorus,
which presents great difficulties, the inventors generally prefer to intimately mix
the toluene-monosulphonates of sodium with phosphorus-trichloride and to pass a
current of chlorine over this mixture until the reaction is completed. The con-
version goes on smoothly and uniformly when the temperature generated within
the apparatus is properly regulated by cooling the latter with water.
phosphorus-oxychloride resulting from the decomposition taking place, is driven off,
collected and reutilized as will be described more specially hereafter.
$
The
The two toluene-sulphochlorides remaining in the apparatus, are allowed to cool
slowly whereby the solid one is deposited in large crystals, so that the liquid one
can easily be removed therefrom by suitable mechanical means, preferably by aid
of a centrifugal machine. A repeated washing of the remaining solid part with
cold water is essential to effect a complete separation.
The solid part, remaining in the form of large crystals in the centrifugal machine,
is reutilized as described below.
The liquid part, i.e., the ortho-toluene-sulphochloride, is cooled by ice to separate
out as much as possible of the para-toluene-sulphochloride, and thereupon subjected
again to the action of a centrifugal machine.
Operation VI. The liquid ortho-toluene-sulphochloride has to be converted into
the ortho-toluene-sulphoamide. This is effected by means of dry ammonia gas, or
aminonia-carbonate, the latter being more advantageous on account of its solid
state. The ortho-toluene-sulphochloride and the solid ammonia-carbonate are
mixed together in the proportions required, and the mixture, which forms a thick.
pulp, is then subjected to the action of steam. Carbonic acid is set free, and the
remaining mass consists of ortho-toluene-sulphamide and chloride of aminonium.
As this mass is very liable to solidify in cooling, cold water is at once added thereto,
whereby the chloride of ammonium is readily dissolved, whilst the amide remains
in solid state. The liquid is separated by means of a centrifugal inachine.
In case dry ammonia-gas is used to form the amide, the operation should be
carried out in closed vessels, arranged in series.
From the chloride of ammonium obtained by the said treatment of the sulpho-
chloride, the caustic ammonia or ammonia-carbonate may be produced which is
required in a subsequent operation.
Operation VII. The ortho-toluene-sulphamide coming from the centrifugal
machine or the filter-press, is finally converted into anhydro-ortho-sulphamine-
benzoic acid or benzoic sulphinide or saccharine. This is effected by oxydation.
The oxydation may be performed by any of the known oxydizing agents. The
inventors however prefer..to employ for this purpose permanganates and particularly
potassic permanganate. The result of the oxydation will then be precipitated

page_text: insoluble manganese-dioxyde, free alkali and carbonate of alkali, and an 'ortho-
sulphamine-benzoate, the base of which corresponds to that of the permanganate
employed. The alkaline liquor thus obtained must be carefully neutralized during
the process of oxydation and especially before evaporating, with a mineral acid, as
otherwise the ortho-sulphamine-benzoate formed would be decomposed into Ortho-
sulphobenzoate and free ammonia, as will clearly be seen from the following
formula:
CHA
CO O Na
SO. NH.
+NaOH= C H
SO, O Na+ NH,
From the ortho-sulphamine-benzoate pure arhydro-ortho-sulphamine-benzoic
acid or benzoic sulphinide or saccharine is obtained by precipitation with diluted
mineral acids, as for instance hydrochloric acid, sulphurous acid, &c.
The precipitated manganese-dioxyde, which has to be separated from the liquor
by filtration, may be transformed again into permanganate by means of any of the
methods known for this purpose..
The successive steps of the transformation of toluene into anhydro-ortho-
sulphamine-benzoic acid or benzoic sulphinide or saccharine may be expressed by
the following formulae.

page_text: The solid para-toluene-sulphochloride formed is decomposed into toluene, hydro-
5 chloric acid and sulphurous acid, by mixing it with carbon, by moistening the mixture
and subjecting it under pressure to the action of superheated steam. The reaction
is as follows:
1., CH
2
SO, CI+ H₂O-C, H₁<
UH
SO, OH
+ H Cl
The toluene is used in operation I.
The phosphorus-oxychloride resulting in the production of the sulphochlorides,
as described, and containing nearly three fifths of the total chlorine employed and
all the phosphorous, is utilized for developing chlorine from bleaching-powder. For
this purpose it is decomposed by water into hydrochloric acid and phosphoric acid
which in their turn are made to act on bleaching-powder, whereby chlorine is set
free under formation of chloride and phosphate of lime :
-
4 Ca
+ 2 PO Cl₂ + 5 H₂ O =P₂ O, Ca H₁ + 8 Cl + 3 Ca Cl₂ + 3 H₂ O
This phosphate can easily be obtained in pure state and is well adapted for the
production of phosphorus or for use as a fertilizer.
Having now particularly described and ascertained the nature of this invention
and the manner in which it is to be performed, as communicated to me by my
correspondents, I declare that what I claim. is
1. The process described as first method for manufacturing anhydro-ortho-
sulfaminebenzoic acid or benzoic sulphinide or saccharine with employment of one
or all of the reactions set forth in the specification.
2. The production of anhydrous ortho-sulphamine-benzoic acid
ог benzoic
sulphinide or saccharine by means of the methods described in the preceding
specification.
JAMES Y. JOHNSON.