Note: Descriptions are shown in the official language in which they were submitted.
21064 15
Process for the preparation of endo/exo-8-N,N-dialkyl
amino-exo-tricyclo[5.2.1.02~~ decane
The invention relates to a process for the preparation of
endo/exo-8-N,N-dialkylamino-exo-tricyclo[5.2.1.0z~6]decane
from the corresponding 8-hydroxy compound. Quaternary
ammonium salts of diaminotricyclo[5.2.1.02'6]decane are
used, inter alia, during the preparation of synthetic
zeolites as so-called templates, i.e. as molecular
negative forms which stabilize the mineral structure
during crystallization.
The preparation of 8-N,N-dialkylamino-tricyclo-
[5.2.1.02'6]decane is known. P. Wilder et al. (J. Am.
Chem. Soc. 81 (1959), 655 et seq.) prepare this compound
~rom the oxime of 8-ketotricyclo[5.2.1.0z~6]decane, which
is reduced with sodium to give 8-aminotricyclo-
[5.2.1.02'6]decane. The dimethyl compound is finally
obtained in a moderate yield by reaction of the primary
amine with a mixture of formic acid and an aqueous
formaldehyde solution.
The process described in WO 90/04567 also starts from 8-
ketotricyclo[5.2.1.026]decane to obtain 8-N,N-dialkyl-
amino-tricyclo[5.2.1.02'6]decane. It is reacted with
dialkylformamide (in which alkyl is a methyl, ethyl or
propyl radical), in the presence of formic acid in a
closed system at 160 to 195°C. The reaction time is 10 to
50 hours.
The known syntheses do not yet meet all the demands made
on a process which is to be carried out on an industrial
scale. They require the use of expensive chemicals and
long reaction times, which impair the economy of the
process, and produce the desired product in only a
moderate yield.
There was therefore the object of developing a process
which avoids the disadvantages described and leads to the
desired dialkylamino compound in an industrially simple
21084 15
- 2 -
manner using inexpensive starting substances.
According to the present invention there is
provided a process for preparing an endo/exo-8-N,N-
dialkylamino-exo-tricyclo[5.2.1.02 6]decane, which process
comprises reacting 8-hydroxytricyclo [5.2.1.0 2 6] decane with
a secondary amine of the formula HNR1R2, in which R1 and R2
are identical or different and are in each case an alkyl
radical having 1 to 6 carbon atoms, at 120 to 250°C in the
presence of a hydrogenation catalyst and hydrogen, wherein
the water formed during the reaction is removed continuously
and the hydrogen is fed to the reaction mixture in an amount
of 5 to 300 1 / 1 of catalyst .
The novel process is surprisingly selective and
produces endo/exo-8-N,N-dialkylamino-exo-tricyclo(5.2.1.02~6]
decane in a high yield; the amino compound can be isolated
from the reaction mixture in a pure form by simple
dist i l lat ion .
The 8-hydroxytricyclo[5.2.1.02~6Jdecane employed as
the starting compound is a substance which is commercially
available and is prepared from tricyclo[5.2.1.0 2 6]deca-3,8-
diene (cyclopentadiene) by adding on water in the presence of
acid catalysts and subsequent hydrogenation of the
hydroxytricyclodecene. It can be used in the commercially
available form, i.e., for example, without prior fine
purif icat ion .
According to the invention, the hydroxy-
tricyclodecane is allowed to react with a secondary amine of
the formula HNR1R2. R1 and R2 can be identical or different.
24325-209
z~os~~5
- 2a -
They are alkyl radicals having 1 to 6, preferably 1 to 4, and
in particular 1 to 3 carbon atoms. Suitable amines are
dimethylamine, diethylamine, di-n-propylamine, di-n-
butylamine, di-i-butylamine, di-n-pentylamine, di-3-methyl-
butylamine, di-n-hexylamine, di-i-hexylamine, N-methyl-
ethylamine, N-methylpropylamine, N-methylbutylamine, N-
methyl-pentylamine, N-methylhexylamine, N-ethylpropylamine,
N-ethyl-butylamine, N-ethylpentylamine, N-ethylhexylamine, N-
propyl-butylamine, N-propylpentylamine,
24325-209
21084 15
- 3 -
N-propylhexylamine, N-butylpentylamine and N-butylhexyl-
amine, in particular dimethylamine, diethylamine and di-
n-propylamine, preferably dimethylamine.
The reactants are usually reacted in equimolar amounts;
however, it is also possible to use one of the reactants
in excess.
The reaction between the hydroxy compound and secondary
amine is carried out in the presence of catalysts.
Although the reaction is not a hydrogenation and hydrogen
does not participate directly in the reaction between the
starting substances, conventional hydrogenation cata-
lysts, for example those based on nickel and cobalt, have
proven appropriate for carrying out the reaction. Copper
catalysts which, unexpectedly, have an extremely selec-
tive action, are employed particularly successfully.
Copper supported catalysts having a copper content of 15
to 85, in particular 50 to 70~ by weight (based on the
catalyst) are preferably suitable. They comprise as
supports silicic acid, kieselguhr, aluminum oxide,
magnesium oxide, carbon or pumice, preferably kieselguhr
or aluminum oxide, and if appropriate customary activa-
tors and additives, such as magnesium or chromium. The
amount of catalyst depends on the content of the hydroxy
compound in the reaction mixture. 0.5 to 30, in parti-
cular 3 to 20$ by weight of catalyst, based on the
hydroxy compound, is usually used. Hydrogen is fed
continuously to the reaction mixture in an amount of 5 to
300, in particular 20 to 100 1/1 of catalyst, in order to
activate the catalysts and to maintain their activity
over the entire reaction time.
The reaction between the reactants proceeds at tempera-
tures of between 120 and 250, in particular 145 to 195°C,
preferably under normal pressure, although a slight
increased pressure of up to 0.1 MPa, in particular up to
0.05 MPa, can be used. According to a proven embodiment,
the secondary amine is added to the stirred suspension of
-4- 2108415
8-hydroxytricyclo [ 5 . 2 .1. 026 ] decane and the catalyst . Both
the amine and the tricyclodecane can be employed as a
solution, for example using toluene or xylene as the
solvent . To ensure that the reaction proceeds rapidly and
completely, it is necessary to provide for continuous
removal of the water formed during the reaction. This is
effected by the processes known in the chemical industry,
for example with the aid of a water separator or phase
separator, or by azeotropic distillation. The reaction
conditions mentioned ensure that the endo/exo isomer is
preferentially formed.
The novel procedure can be carried out either contin-
ucausly or, in particular, discontinuously.
The endo/exo-8-N,N-dialkylamino-exo-tricyclo[5.2.1.0~~6]-
decane is removed from the reaction mixture by simple
distillation and is obtained by this procedure in such a
pure form that no further purification is necessary for
most intended uses.
The preparation of endo/exo-8-N,N-dimethylamino-exo-
tricyclo[5.2.1.026]decane by the novel process is illus-
trated in more detail in the following examples. It is of
course not intended to limit the invention to these
specific embodiments.
Example 1: Preparation of endo/exo-8-N,N-dimethylamino-
exo-tricyclo[5.2.1.026]decane
2280 g (15 mol) of 8-hydroxy-tricyclo[5.2.1.026]decane
and 228 g of a copper supported catalyst (RCH 60/35;
commercial product from Hoechst AG, Cu content about 60~
by weight, based on the catalyst composition) are
initially introduced into a 4 1 three-necked flask
provided with a stirrer, thermometer, water separator,
reflux condenser and inlet tube, and are heated, while
stirring. When a temperature of 100°C has been reached,
20 to 25 1/hour of hydrogen are continuously fed in via
-5- ~ 2~oa~~5
the inlet tube to activate the catalyst, and 125 g/hour
(2.78 mol) of dimethylamine in gaseous form are simul-
taneously fed in via the same inlet tube.
Water is collected in the separator for the first time at
a temperature of 14 8 to 150 °C . To accelerate the reac-
tion, the temperature is adjusted to 170 to 175°C and the
continuous addition of hydrogen and dimethylamine is
continued. The water of reaction formed is constantly
removed by the separator. After 6 hours, no further
discharge of water is observed. 328 g of water of reac-
tion are obtained in total, some of the excess dimethyl-
amine being dissolved in it.
After cooling, the reaction product is filtered and
analyzed by gas chromatography. The crude amine still
contains 2 . 98 ~ of residual 8-hydroxy-tricyclo [ 5 . 2 .1. 026 ] -
decane, which corresponds to a conversion of about 97~.
The selectivity for endo/exo-8-N,N-dimethylamino-exo-
tricyclo[5.2.1.026]decane is 80.8, and the ratio of endo
to exo compound is 61 : 39.
Example 2
Example 1 is repeated, with the difference that the
reaction temperature is 160 to 165°C. The water of
reaction formed is again removed from the reaction
mixture constantly by the water separator. After 6 hours,
no further discharge of water is observed. 312 g of water
of reaction are obtained in total, some of the excess
dimethylamine being dissolved in this. The cooled and
filtered crude amine still contains 3.75 of 8-hydroxy-
tricyclo[5.2.1.02'6]decane, according to determination by
gas chromatography, which corresponds to a conversion of
about 96.2.
The selectivity for endo/exo-8-N,N-dimethylamino-exo-
tricyclo[5.2.1.0z~6]decane is 80.2, and the ratio of endo
- 6 -
to exo compound is 81 : 19. 2 1 0 8 ~ ~ 5
Example 3
Example 1 is repeated, with the difference that the
reaction temperature is 150 to 155°C. The water of
reaction formed is again removed from the reaction
mixture constantly by the separator. After 6 3/4 hours,
no further discharge of water is observed. 284 g of water
of reaction are obtained in total, some of the excess
dimethylamine being dissolved in this. The cooled and
filtered crude amine still contains 8.84 of 8-hydroxy-
tricyclo[5.2.1.0z~6]decane according to analysis by gas
chromatography, which corresponds to a conversion of
about 91.28.
The selectivity of endo/exo-8-N,N-dimethylamino-exo-
tricyclo[5.2.1.02'6]decane is 86.1$, and the ratio of endo
to exo compound is 95 . 5.
