Improvements in the Manufacture of Alpha-beta-di-methyl- eurhodines.
Year: 1893

page_text: Date of Application, 9th Oct., 1893
Complete Specification Left, 3rd July, 1894-Accepted, 4th Aug.,
1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Alpha-beta-di-methyl-
eurhodines.
I JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of
Middlesex Gentleman do hereby declare the nature of this invention (which has
been communicated to me by The Badische Anilin and Soda Fabrik of Ludwig-
shafen-on-Rhine in the Empire of Germany) to be as follows :-
In the Specifications of Letters Patent No. 10138 and No. 10138A of 1892
granted to me on a communication of my present correspondents the production
alpha-beta-dimethyl-homo-eurhodine is described. The present invention relates
to modifications of the processes therein described for obtaining such bodies.
of
In the said Specifications examples are given for the production of alpha-
methyl-homo-eurhodine by the interaction of an amido-azo compound of para-
toluidine with methyl-alpha-naphthylamine and for the conversion of this
intermediate product into the desired dimethyl-eurhodine by alkylation. Now my
foreign correspondents have discovered that both alkyl groups may be directly
introduced into non-alkylated eurhodines by suitable treatment with alkyl-iodides.
Thus by treating homo-eurhodine (C₁,H,N) with methyl iodide in the first
instance a mixture is obtained, consisting of the iodohydrates of alpha-methyl
homo-eurhodine, alpha-beta-di-methyl-homo-eurhodine and of the unchanged homo-
eurhodine itself. These are preferably reconverted into the respective bases and
again treated with methyl-iodide, and the cycle of operations repeated again and
again, if necessary, until the whole is converted into the desired di-methyl-homo-
eurhodine.
The following example will serve to further illustrate the nature of the
invention but it is not confined thereto.
The parts are by weight.
13
Heat together in an enamelled autoclave about twenty six parts of homo-
eurhodine (C,,H₁N.) about thirty parts of methyl iodide and about one hundred
and fifty parts of methyl alcohol. Maintain the heat at about one hundred and
twenty degrees centigrade for about four hours. Then dilute the product with
water and collect the precipitate on the filter. Treat it whilst in a state of fine
division with about two hundred parts of alcobol and about forty two parts of
caustic soda lye (containing about 28 per cent. NaOH) allow to cool precipitate
the bases with water wash press and dry. Next treat the dry residue again with
thirty parts of methyl-iodide and one hundred and fifty parts methyl alcohol for
about four hours at about one hundred and twenty degrees centigrade and work
up the product in the way hereinbefore described.
If the product still contains an essential quantity of eurhodine or alpha-methyl-
eurhodine the treatment with methyl-iodide is to be repeated. The presence of
these bodies can be ascertained as follows: Dissolve the product in dilute hydro-
chloric acid avoiding excess, then carefully saturate with ammonia, any eurhodine
or alpha-methyl-eurhodine will separate out as a yellow-precipitate while the
alpha-beta-dimethyl-eurhodine remains in solution.
Extract the raw base finally obtained by boiling with about one thousand parts
of water containing one quarter per cent. of hydrochloric acid. Filter the extracts
and treat with salt solution, when cold taking so much that the mother liquor
remains merely slightly coloured. Collect the precipitate wash first with dilute
salt solution and finally with a little water. To purify the dye from any homo-
eurhodine or alpha-methyl-homo-eurhodine that may be present, dissolve it in

page_text: water, add ammonia in slight excess, and stirr for half an hour, filter from the
precipitate formed and add common salt to the filtrate. The alpha-beta-dimethyl-
eurhodine is precipitated in the form of hydrochlorate. Filter, press, and dry.
Dated this 9th day of October 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Alpha-beta-dimethyl-
eurhodines.
1 JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of
Middlesex Gentleman do hereby declare the nature of this invention (which
has been communicated to me from abroad by The Badische Anilin and
Soda Fabrik of Ludwigshafen-on-Rhine in the Empire of Germany) and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
In the Specifications of Letters Patent No. 10138 and No. 10138A of 1892
granted to me on a communication of my present correspondents, the production of
alpha-beta-dimethyl-homo-eurhodine is described. The present invention relates
to modifications of the processes therein described for obtaining such bodies.
In the said Specifications examples are given for the production of alpha-methyl-
homo-eurhodine by the interaction of an amido-azo-compound of para-toluidine
with methyl-alpha-naphthylamine, and for the conversion of this intermediate
product into the desired dimethyl-eurhodine by alkylation. Now my foreign
correspondents have discovered that both alkyl groups may be directly introduced
into nonalkylated eurhodines by suitable treatment with an alkyl-iodide. Thus by
treating homo-eurhodine (C₁,H13N3) with methyl-iodide, in the first instance a
mixture is obtained consisting of the iodohydrates of alpha-methyl-homo-eurhodine,
alpha-beta-dimethyl-homo-eurhodine and of the unchanged homo-eurhodine itself.
These are reconverted into the respective bases and again treated with methyl-
iodide and the cycle of operations repeated, again and again, if necessary until
practically the whole is converted into the desired dimethyl-homo-eurhodine.
The following example will serve to further illustrate the nature of the invention
and the manner in which it is carried into practical effect but the invention is not
confined to the example. The parts are by weight.
Heat together in an enamelled autoclave about twenty six parts of homo-
eurhodine (C1,H₁,N,) about thirty parts of methyl iodide and about one hundred
and fifty parts of methyl-alcohol. Maintain the heat at about one hundred and
twenty degrees centigrade for about four hours. Then dilute the product with
water and collect the precipitate on the filter. Treat it whilst in a state of fine
division with about two hundred parts of alcohol and about forty two parts of
caustic soda lye (containing about twenty eight per cent. NaOH) allow it to cool,
precipitate the bases with water, wash, press and dry. Next treat the dry residue
again with thirty parts of methyl-iodide and one hundred and fifty parts methyl
alcohol for about four hours, at about one hundred and twenty degrees centigrade
and work up the product in the way hereinbefore described. If the product still
contain an essential quantity of eurhodine, or alpha-methyl-eurhodine, the treatment
with methyl-iodide is to be repeated. The presence of these bodies can be
ascertained as follows:-
-
Dissolve the product in dilute hydrochloric acid, avoiding excess, then carefully
saturate with ammonia; any eurhodine, or alpha methyl eurhodine, will separate
out as a yellow precipitate, whilst the alpha-beta-dimethyl curhodine remains in
solution.
Extract the raw base, finally obtained by boiling with about one thousand parts

page_text: of water containing one quarter per cent. of hydrochloric acid. Filter the extracts
and treat with salt solution when cold taking so much that the mother liquor
remains merely slightly coloured. Collect the precipitate and wash first with dilute
salt solution, and finally with a little water. To purify the dye from any homo-
eurhodine, or alpha-methyl-homo-eurhodine that may be present, dissolve it in water
add ammonia in slight excess and stir for half an hour; filter from the precipitate
formed and add common salt to the filtrate. The alpha-beta-dimethyl eurhodine is
precipitated in the form of hydrochlorate. Filter, press, and dry.
The lower homologous alpha-beta-dimethyl-eurhodine can be similarly obtained
by treating the lower homologous eurhodine (C₁,H,,N) in the same way.
11
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The manufacture of alpha-beta-dimethyl-eurhodines by directly alkylating
eurhodines by repeated treatment with methyl iodide substantially as herein before
described.
2. The manufacture of alpha-beta-dimethyl-homo-eurhodine by proceeding as
hereinbefore described in the example.
JOHNSONS & WILLCOX,
Agents.