Year: 1896

page_text: Date of Application, 21st May, 1896..
Complete Specification Left, 17th Feb., 1897-Accepted, 3rd Apr., 1897

page_text: The bodies obtained by this invention form soluble bodies of the nature of organic
salts by virtue of the basic character of (for example) piperidine on the one hand and
the acid character of (for example) pyrogallic acid on the other hand.
Dated this 21st day of May 1896.
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.
24-8 kilos. of guaiacol are dissolved in 8.5 kilos. of piperidine in a vessel which it is
best (but not necessary) to provide with a suitable cooling apparatus, as considerable
heat is evolved by the chemical action.
After a time the contents of the vessel become solid, more especially if a few
crystals of the compound are introduced into the liquid. The product thus obtained
is re-crystallized from a suitable solvent, and in this case a mixture of benzol and
petroleum spirit is considered best. The crystals obtained are colorless prisms or
plates of considerable size, fairly soluble in water and most organic solvents. The
melting point of these crystals is 79° to 81° C. The compound inay also be obtained
in a pure state by dissolving the piperidine in petroleum ether, and the guaiacol in
benzene, and mixing the solutions, or by pouring the liquid first obtained by the
action of the two constituents into a mixture of petroleum ether and benzol. The
crystals form very rapidly in the solution on cooling or on the addition of a few
crystals.
We are aware that B. v. Lachowicz (Wiener Monatshefte fur Chemie 1888, 505)
obtained a body by the action of hydroquinone on piperidine in alcoholic solution, to
which he gave the name of di-piperil-benzo-quinone, but di-piperil-benzo-quinone has

page_text: very different characteristics from the body obtained by our invention. Di-piperil-
benzo-quinone has the character of a dyestuff and is a deep red. If, however,
hydroquinone is allowed to act on piperidine in ethereal solution, a perfectly white
body is obtained, which if left to stand in solution would be slowly transformed
into the red body obtained by Lachowicz. The white product which is obtained
according to our invention has a melting point of 106°-107° C. and is easily
soluble in water and most solvents, whereas the red body above mentioned melts
at 178° C. and is insoluble in water and fairly insoluble in most organic solvents.
It is characteristic of most of the bodies obtained by our invention that they are
easily soluble in water.
The bodies obtained by our invention form soluble bodies of the nature of organic
salts by virtue of the basic character of (for example) piperidine on the one hand and
the acid character of (for example) pyrogallic acid or guaiacol on the other hand.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. The manufacture of derivatives of piperidine by the action of guaiacol on
piperidine or its homologues either alone or in the presence of a suitable solvent, such
as a mixture of benzol and petroleum spirit, substantially as described.
2. The manufacture of derivatives of piperidine by the action of hydroquinone,
tannic acid, pyrogallic acid, the nitro phenols, 1, 2, 4 nitro-alpha-naphthol, meta
nitro benzoic acid or di-nitro-benzoic acid 1, 3, 5 on piperidine or its homologues
either alone or in the presence of a suitable solvent and with or without heat,
substantially as described.
3. As new products, the bodies derived from piperidine or its homologues, having
the characteristics as herein before described.
Doted this 17th day of Fornom 1807
J. C. MEWBURN & ELLIS,
55 and 56 Chancery Lane, London, Chartered Patent Agents.