Cyclohexane derivatives containing carboxyl groups

Cyclohexane derivatives containing carboxyl groups with the general structure of formula (I): ##STR1## alone or in mixtures with one another, in which the substituents on the cyclohexane ring are in the 1-, 2-, and 4-positions, Z is a --CH.sub.2 --CH.sub.2 -- group or a ##STR2## group, R is an alkyl group with 1 to 10 carbon atoms, and n is an integer of 1 to 3, are obtained by the hydrocarboxyalkylation of 1,2,4-trivinylcyclohexane and are useful as monomers for the formation of polymers.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to novel cyclohexane derivatives containing 
carboxyl groups of formula (I): 
##STR3## 
in which the substituents, --Z--COOR).sub.n and 
--CH.dbd.CH.sub.2).sub.3-n, are in the 1-, 2-, and 4-positions of the 
cyclohexane ring, Z is a --CH.sub.2 --CH.sub.2 -- group (ethylene group) 
or a 
##STR4## 
group (ethylidene group), R is an alkyl group having 1 to 10 carbon atoms, 
and n is an integer of 1 to 3, and mixtures thereof; a method for 
producing such cyclohexane derivatives; and polymers prepared from such 
cyclohexane derivatives. 
2. Discussion of the Background 
Cyclohexane derivatives containing carboxyl groups are of great interest as 
monomers and comonomers for the production of polymers. 
1,2,4-trivinylcyclohexane, which is used as a starting material in the 
method according to the present invention, can be obtained, for example, 
according to R. Rienacker, Brennstoff-Chemie, vol. 45, p. 206 (1964), by 
pyrolysis of 1,5,9-cylcododecatriene. 
According to DE-B 29 12 489, monoolefins with an internal carbon-carbon 
double bond can be hydrocarboxyalkylated in the presence of a cobalt 
compound as the catalyst and pyridine or a non-ortho-alkylated pyridine as 
the promoter, at a termperature of 165.degree. to 195.degree. C. and a 
pressure of 150,000 to 300,000 hPa (hectopascals). However, this reference 
provides no information concerning the behavior of dienes or polyenes 
under these conditions. 
J. Falbe, Synthesen mit Kohlenmonoxid, Berlin - Heidelberg - New York, 
1967, states that 1,5-cyclooctadiene is hydrocarboxyalkylated either to an 
unsaturated monocarboxylic acid ester or to a saturated dicarboxylic acid 
ester with a palladium catalyst. In the analogous hydrocarboxylation of 
1,5-cyclooctadiene with a cobalt catalyst, however, only a saturated 
monocarboxylic acid is obtained. Therefore, of the two internal double 
bonds, one is hydrocarboxylated and one is hydrogenated on the cobalt 
catalyst. 
According to U. Buller (dissertation, Technical University of 
Rhineland-Westphalia in Aachen, 1980), .alpha.,.omega.-dienes react with 
carbon monoxide and an alcohol at 130.degree. to 140.degree. C. to form 
dicarboxylic acid esters, with high selectivity. 
In DE-A 38 12 184, reactive .alpha.,.omega.-dienes are 
hydrocarboxyalkylated on cobalt catalysts. Here, .omega.-enecarboxylic 
acid esters are obtained at 100.degree. to 200.degree. C. and 150,000 to 
350,000 hPa. Therefore, only one of the terminal position double bonds is 
hydrocarboxyalkylated, and one double bond is retained. However, the 
conversion yields of the .alpha.,.omega.-dienes are always below 50% in 
the examples. 
Accordingly, prior to the present invention, it was not known that terminal 
position trienes could be hydrocarboxyalkylated. It was also unknown what 
products hydrocarboxyalkylation of such trienes would yield. 
Thus, there remains a need for cyclohexane derivatives which contain 
carboxyl groups. These also remains a need for a method which produces 
cyclohexane derivatives which contain carboxyl groups. 
SUMMARY OF THE INVENTION 
Accordingly, it is one object of the present invention to provide novel 
cyclohexane derivatives containing carboxyl groups. 
It is another object of the present invention to provide a method for 
preparing such cyclohexane derivatives. 
It is another object of the present invention to provide polymers which are 
prepared from such cyclohexane derivatives. 
These and other objects, which will become apparent in the course of the 
following detailed description, have been achieved by the inventors' 
discovery that 1,2,4-trivinylcyclohexane can be reacted with an alcohol 
having 1 to 10 carbon atoms and carbon monoxide, in the presence of a 
cobalt catalyst and a tertiary amine, at a temperature of 120.degree. to 
170.degree. C., and a pressure of 150,000 to 350,000 hPa, for a time of 6 
to 48 hours, to yield cyclohexane derivatives of formula (I) 
##STR5## 
in which the substituents, --Z--COOR).sub.n and 
--CH.dbd.CH.sub.2).sub.3-n, are in the 1-, 2-, and 4-positions of the 
cyclohexane ring, Z is a --CH.sub.2 --CH.sub.2 -- group (ethylene group) 
or a 
##STR6## 
group (ethylidene group), R is an alkyl group having 1 to 10 carbon atoms, 
and n is an integer of 1 to 3; and that such compounds are useful as 
monomers for the production of polymers. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Thus, in one embodiment, the present invention provides a method for 
preparing cyclohexane derivatives which contain carboxyl groups. 
Generally, the present method yields the present cyclohexane derivatives 
as a mixture. The mixture obtained by the present method generally does 
not contain the present compounds in approximately equal amounts. Instead, 
the method yields several compounds as main products, while others are 
formed as by-products o only in trace amounts. 
The present compounds can be individually isolated from the reaction 
mixture, using known conventional methods, such as chromatography or 
fractional distillation. 
However, it is to be understood that both the individual compounds and also 
the mixtures thereof are within the scope of the present invention. 
In the hydrocarboxyalkylation, alcohols having 1 to 10 carbon atoms are 
suitably used. Examples include methanol, ethanol, n-propanol, 
isopropanol, n-butanol, isobutanol, hexanol, 2-ethylhexanol, and 
n-octanol. Alcohols with 1 to 4 carbon atoms are preferred, with methanol 
being very especially preferred. The alcohol is both a reagent and a 
solvent in the reaction. 
Another starting material is, of course, 1,2,4-trivinylcyclohexane. 
Preferably, 1,2,4-trivinylcyclohexane and the alcohol are used in a molar 
ratio of 1:1 to 1:10, more preferably 1:2 to 1:8. 
A suitable cobalt compound for the catalytic hydrocarboxyalkylation of 
1,2,4-trivinylcyclohexane is hydridocobalt tetracarbonyl, HCo(CO).sub.4. 
However, cobalt salts, such as cobalt (II) acetate, cobalt (II) 
naphthenate, cobalt (II) stearate, cobalt (II) carbonate or cobalt (II) 
chloride, cobalt oxides or cobalt complexes, such as dicobalt 
octacarbonyl, can also be used. 
These cobalt compounds require 0.1 to 10 mole-% hydrogen, H.sub.2, based on 
the number of moles of carbon monoxide, in the initial phase of the 
hydrocarboxyalkylation. The presence of the hydrogen causes hydridocobalt 
tetracarbonyl to be formed under the stated reaction conditions, which is 
presumably the actual catalytically active compound. 
A slight initial content of hydrogen is also helpful when using 
hydridocobalt tetracarbonyl, since hydrogen regenerates used catalyst. 
It is suitable to use 0.5 to 10 mole-% of the cobalt compound, preferably 1 
to 5 mole-% of the cobalt compound, based on the number of moles of 
1,2,4-trivinylcyclohexane. 
As the tertiary amine which acts as the promoter, pyridine and 
non-ortho-alkylated pyridines, such as 3- and 4-picoline, 3,4- and 
3,5-lutidine, 3- and 4-ethyl pyridine or other 3- and 4-alkyl pyridines, 
in which alkyl can be propyl, i-propyl, butyl, i-butyl or t-butyl, can be 
used. Preferably, non-ortho-alkylated pyridines are used, with 4-picoline 
being very especially preferred. 
The molar ratio of tertiary amine to cobalt compound is suitably 2:1 to 
50:1. 
In the hydrocarboxyalkylation, the pressure is suitably 150,000 to 350,000 
hPa, preferably 200,000 to 350,000 hPa. The reaction is generally carried 
out in an autoclave. The pressure may be adjusted by adding or releasing 
CO. Thus, amount of CO present will in effect be determined by the 
reaction temperature and pressure selected. 
In a first preferred embodiment, the present invention relates to compounds 
with the general structure of formula (II): 
##STR7## 
alone or in mixtures with one another, their production, and polymers 
prepared from such compounds. 
For the production of the compounds of formula (II), 
1,2,4-trivinylcyclohexane is reacted with an alcohol having 1 to 10 carbon 
atoms and carbon monoxide, in the presence of a cobalt catalyst and a 
tertiary amine, at a temperature of 120.degree. to 140.degree. C., and a 
pressure of 150,000 to 350,000 hPa, for a time of 6 to 18 hours. 
In this embodiment, a product mixture is obtained which generally contains 
compounds having the structures of formulae (V)-(X): 
##STR8## 
In another preferred embodiment, the present invention relates to compounds 
with the general structure of formula (III): 
##STR9## 
alone or in mixtures with one another, their production, and polymers 
prepared from such compounds. 
For the production of the compounds of formula (III), 
1,2,4-trivinylcyclohexane is reacted with an alcohol having 1 to 10 carbon 
atoms and carbon monoxide, in the presence of a cobalt catalyst and a 
tertiary amine, at a temperature of 130.degree. to 160.degree. C., and a 
pressure of 150,000 to 350,000 hPa, for a time of 12 to 24 hours. 
In this embodiment, a product mixture is obtained which generally contains 
compounds having the structures of formulae (XI)-(XXII): 
##STR10## 
In a third preferred embodiment, the invention relates to compounds with 
the general structure of formula (IV) 
##STR11## 
alone or in mixtures with one another, their production and polymers 
prepared from such compounds. 
For the production of the compounds of formula (IV), 
1,2,4-trivinylcyclohexane is reacted with an alcohol having 1 to 10 carbon 
atoms and carbon monoxide, in the presence of a cobalt catalyst and a 
tertiary amine, at a temperature of 130.degree. to 170.degree. C., and a 
pressure of 150,000 to 350,000 hPa, for a time of 36 to 48 hours. 
In this embodiment, a product mixture is obtained which generally contains 
compounds having the structures of formulae (XXIII)-(XXX): 
##STR12## 
The method according to the present invention generally yields the present 
cyclohexane derivatives containing carboxyl groups in high yields, with 
great selectivity. 
The compounds of formula (II) are obtained with a selectivity of more than 
75%. The compounds of formula (III) are obtained with a selectivity of 
more than 55%, at a yield of more than 90%. The production method 
according to the present invention also yields the compounds of formula 
(IV) in a yield of more than 95%, with a selectivity of more than 75%. 
In another embodiment, the present invention relates to polymers prepared 
from the present cyclohexane derivatives and a method for preparing such 
polymers. The present cyclohexane derivatives containing carboxyl groups 
can be used alone or in mixtures with one another, as monomers or 
comonomers, in any conventional polymerization or polycondensation 
process. 
In the polymerization of the present cyclohexane derivatives, comonomers 
such as ethylene, propene, isobutene, 1-butene, 1-pentene, isoprene or 
butadiene, are preferably also used. 
Other suitable comonomers are, for example, acrylic acid, C.sub.1-4 -alkyl 
acrylic acid esters, acrylic acid nitrile, acrylamide, N-C.sub.1-4 -alkyl 
acrylic acid amides, methacrylic acid, C.sub.1-4 -alkyl methacrylic acid 
esters, methacrylamide, N-C.sub.1-4 -alkyl methacrylic acid amides, maleic 
acid anhydride, C.sub.1-4 -alkyl maleic acid half esters or whole esters, 
maleic acid amide, N-C.sub.1-4 -alkyl maleic acid amides, maleimide, 
N-C.sub.1-4 -alkyl maleic acid imides, vinyl acetate, acrylonitrile, 
methacrylonitrile, styrene, .alpha.-methylstyrene, vinyl chloride, vinyl 
fluoride or vinylidene fluoride. 
The present cyclohexane derivatives containing carboxyl groups can also be 
used alone or in mixtures with one another, as monomers, in 
polycondensation processes. Thus, they can be used for the production of 
alkyd resins, polyesters (with, e.g., C.sub.1-8 -alkylene diols, such as 
ethylene glycol, propylene glycol, butylene glycol, and 1,6-hexanediol), 
or polyamides (with, e.g., C.sub.1-8 -alkylene diamines, such as 
1,6-hexanediamine). They can also be components of epoxy resins or improve 
lubricants containing ester groups. 
The products according to the present invention can also be used for the 
synthesis of pharmaceutical products, cosmetics, aroma substances and 
plant protectants. 
The polymers and polycondensates prepared from the present cyclohexane 
derivatives are useful for the production of molded articles. Such molded 
articles may be produced by any of the conventional techniques for 
preparing molded articles.

Having generally described this invention, a further understanding can be 
obtained by reference to certain specific examples which are provided 
herein for purposes of illustration only and are not intended to be 
limiting unless otherwise specified. 
EXAMPLES 
In the examples, a 5 liter VA steel autoclave is used. 
The reaction components 1,2,4-trivinylcyclohexane, alcohol, cobalt (II) 
salt and 4-picoline are added in and brought to the reaction temperature. 
Then hydrogen pressure is applied, with the overall pressure being built 
up by the application of carbon monoxide pressure. The pressure drop 
during the reaction is equalized by constant addition of carbon monoxide. 
After the reaction is complete, the mixture is cooled to room temperature 
and brought to atmospheric pressure. The yields determined by gas 
chromatography are indicated in mole-%, based on the amount of 
1,2,4-trivinylcyclohexane used. 
EXAMPLE 1 
Amount weighed in 
908.9 g (5.6 mole) of 1,2,4-trivinylcyclohexane 
717.7 g (22.4 mole) of methanol 
62.6 g (0.672 mole) of 4-picoline 
99.0 g (0.168 mole) of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 130.degree. C.; reaction time: 12 h 
Compounds having the structure of formula (II) are obtained with 77.0% 
selectivity. The remainder contains isomerized initial product and 
compounds with the structure of formula (III). 
The mixture was purified by fractional distillation and collection of the 
fraction distilling at 62.degree. to 70.degree. C. and 0.03 hPa. 
EXAMPLE 2 
Amount weighed in 
762.8 g of 1,2,4-trivinylcyclohexane 
903.5 g of methanol 
52.5 g of 4-picoline 
83.1 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 130.degree. C.; reaction time: 12 h 
Compounds having the structure of formula (II) are obtained with 81.1% 
selectivity. 
EXAMPLE 3 
Amount weighed in 
762.8 g of 1,2,4-trivinylcyclohexane 
903.5 g of methanol 
52.5 g of 4-picoline 
83.1 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =5,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 130.degree. C.; reaction time: 12 h 
Compounds having the structure of formula (II) are obtained with 78.0% 
selectivity. 
EXAMPLE 4 
Amount weighed in 
990.0 g (6.1 mole) of 1,2,4-trivinylcyclohexane 
625.4 g (19.5 mole) of methanol 
68.2 g (0.73 mole) of 4-picoline 
107.8 g (0.183 mole) of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =5,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 130.degree. C.; reaction time: 24 h 
Compounds having the structure of formula (III) are obtained at a yield of 
90.6% with 59.3% selectivity. The remainder contains isomerized initial 
product, monohydrocarboxymethylation product and 
trihydrocarboxymethylation product. 
The mixture was purified by fractional distillation and collection of the 
fraction distilling at 103.degree. to 118.degree. C. and 0.03 hPa. 
EXAMPLE 5 
Amount weighed in 
990.0 g of 1,2,4-trivinylcyclohexane 
625.4 g of methanol 
68.2 g of 4-picoline 
107.8 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =5,000 hPa (initially); p.sub.tot =280,000 hPa 
1st stage 130.degree. C./12 h 
2nd stage 140.degree. C./12 h 
Compounds having the structure of formula (III) are obtained at a yield of 
more than 98%, with 67.1% selectivity. 
EXAMPLE 6 
Amount weighed in 
990.0 g of 1,2,4-trivinylcyclohexane 
625.4 g of methanol 
68.2 g of 4-picoline 
107.8 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 150.degree. C.; reaction time: 12 h 
Compounds having the structure of formula (III) are obtained at a yield of 
more than 99%, with 62.0% selectivity. 
EXAMPLE 7 
Amount weighed in 
990.0 g of 1,2,4-trivinylcyclohexane 
625.4 g of methanol 
68.2 g of 4-picoline 
107.8 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 160.degree. C.; reaction time: 12 h 
Compounds having the structure of formula (III) are obtained at a yield of 
more than 99%, with 59.0% selectivity. 
EXAMPLE 8 
Amount weighed in 
1,136.1 g of 1,2,4-trivinylcyclohexane 
471.0 g of methanol 
78.2 g of 4-picoline 
123.8 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
Reaction temperature: 140.degree. C.; reaction time: 12 h 
Compounds having the structure of formula (III) are obtained at a yield of 
more than 96%, with 57.0% selectivity. 
EXAMPLE 9 
Amount weighed in 
990.0 g (6.1 mole) of 1,2,4-trivinylcyclohexane 
625.4 g (19.5 mole) of methanol 
68.2 g (0.73 mole) of 4-picoline 
107.8 g (0.183 mole) of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
1st stage 130.degree. C./24 h 
2nd stage 160.degree. C./24 h 
Compounds having the structure of formula (IV) are obtained at a yield of 
more than 99%, with 78.4% selectivity. The remainder contains 
di-hydrocarboxymethylation product and products with a high boiling point. 
The mixture was purified by fractional distillation and collection of the 
fraction distilling at 145.degree. to 158.degree. C. and 0.04 hPa. 
EXAMPLE 10 
Amount weighed in 
990.0 g of 1,2,4-trivinylcyclohexane 
625.4 g of methanol 
68.2 g of 4-picoline 
107.8 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
1st stage 130.degree. C./24 h 
2nd stage 170.degree. C./24 h 
Compounds having the structure of formula (IV) are obtained at a yield of 
more than 99%, with 80.0% selectivity. 
EXAMPLE 11 
Amount weighed in 
973.8 g of 1,2,4-trivinylcyclohexane 
595.9 g of methanol 
89.4 g of 4-picoline 
141.8 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
1st stage 130.degree. C./24 h 
2nd stage 170.degree. C./24 h 
Compounds having the structure of formula (IV) are obtained at a yield of 
more than 99%, with 81.8% selectivity. 
EXAMPLE 12 
Amount weighed in 
1,006.3 g of 1,2,4-trivinylcyclohexane 
615.8 g of methanol 
69.3 g of 4-picoline 
109.6 g of Co (II) naphthenate (10% Co) 
Reaction conditions 
p.sub.H2 =10,000 hPa (initially); p.sub.tot =280,000 hPa 
1st stage 140.degree. C./24 h 
2nd stage 170.degree. C./24 h 
Compounds having the structure of formula (IV) are obtained at a yield of 
more than 99%, with 77.0% selectivity. 
Obviously, numerous modifications and variations of the present invention 
are possible in light of the above teachings. It is therefore to be 
understood that, within the scope of the appended claims, the invention 
may be practiced otherwise than as specifically described herein.