A Process for Converting Compounds of the Citral Series (Geranium Series) into Isomers having a Higher Specific Weight and a Lower Boiling Point than the Original Bodies
Year: 1893

page_text: Date of Application, 1 th Nov., 1893
Complete Specification Left, 16th July, 1894-Accepted, 18th Aug.. 1894
PROVISIONAL SPECIFICATION.
A Process for Converting Compounds of the Citral Series (Geranium
Series) into Isomers having a Higher Specific Weight and a
Lower Boiling Point than the Original Bodies.
I, JOHANN CARL WILHELM FERDINAND TIEMANN, member of the Firm of
Haarmann and Reimer, of Holzminden, residing at 18 Bendlerstrasse Berlin, W.
Germany, do hereby declare the nature of this invention to be as follows :—
I have found that the compounds of the citral series (geranium series) are
converted under the action of dilute sulphuric acid into isomers having a higher
specific weight and a lower boiling point than the original bodies.
EXAMPLE III.
By heating in the water bath the hydrocarbon obtained by splitting off carbonic
acid from the geranium acid (geraniolene C,H₁, :) with 60 per cent. sulphuric acid
during 3 or 4 hours, it is converted in an analogous manner into an isomeric
[Price 8d.1

page_text: hydrocarbon, the isogeraniolene, which by extracting with ether, is separated and
purified by rectifying by means of sodium..
For the sulphuric acid used in the above described conversions may be substituted
other weakly condensing agents, such as phosphoric acid, metaphosphoric acid etc.,
which, as is commonly known, act in this respect in the same manner. By
employing sulphuric acid however I have hitherto obtained the best results.
The iso-compounds of the citral series (geranium series) are intended to be used
for perfumery purposes.
Dated this 18th dor of November 1802
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
A Process for Converting Compounds of the Citral Series (Geranium
Series) into Isomers having a Higher Specific Weight and a
Lower Boiling Point than the Original Bodies.
I, JOHANN CARL WILHELM FERDINAND TIEMANN, a member of the Firm of
Haarmann and Reimer of Holzminden, residing at Berlin, Germany, 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:-
I have found that the compounds of the citral series (geranium series) are
converted under the action of dilute sulphuric acid into isomers having a higher
specific weight and a lower boiling point than the original bodies.
If oily geranium acid (CHO) is added with agitation to 70 per cent. sulphuric 3
acid cooled to a temperature below zero C., it is transformed into a solid isomeric
acid, which by pouring the mixture into water, extracting the dilute solution with
ether and crystallising from water or ligroine is obtained in pure crystals.
The geranium acid is liquid, the crystallised isogeranium acid melts at 103.5° C.
The geranium acid boils under a pressure of 13 m.m. at a temperature of 153° C. 3
the isogeranium acid passes over under a pressure of 11 m.m. at a temperature
of 138° C.

page_text: MXAMPLE 111,
By heating in the water bath the hydrocarbon obtained by splitting off carbonic
acid from the geranium acid (geraniolene C,H₁) with 60 per cent. sulphuric acid
during 3 or 4 hours it is converted in an analogous manner into an isomeric
hydrocarbon, the isogeraniolene, which by extracting with ether, is separated and
purified by rectifying by means of sodium.
For the sulphuric acid used in the above described conversions may be substituted
other weakly condensing agents, such as phosphoric acid, metaphosphoric acid etc.,
which, as is commonly known, act in this respect in the same manner. By
employing sulphuric acid however I have hitherto obtained the best results.
The iso-compounds of the citral series (geranium series) are intended to be used
for perfumery purposes.

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
The herein described process for converting compounds of the citral series
(geranium series) into isomers having a lower boiling point and a higher specific
gravity than the original bodies, by subjecting these compounds for some time to
the action of dilute sulphuric acid, or equivalent acids.
Dated this 16th day of July 1894.
ABEL & IMRAY,
Agents for the Applicant.