CH622237A5 - Process for the preparation of tertiary aliphatic amines - Google Patents

Description

The invention relates to a process for the preparation of tertiary aliphatic amines of the formula I.

CH.

N

/ r2

(I),

wherein Ri is a straight-chain or branched, saturated or unsaturated aliphatic radical having 7 to 23 carbon atoms, R2 = Rx-CH2 or CH3 and R3 = CH3 for R2 = 10 Rj-CH2 or R3 = CH3, C2HS, C3H7 or C4H9 for R2 = CH3 is, by reacting aliphatic alcohols and / or aldehydes of the formulas II and / or III

15 Rt-CH2-OH (II) and / or - C

H

(III),

wherein Ri has the same meaning as in formula I, with primary or secondary amines of formula IV

H

N

/ R3

IV

25th

CH.

(IV),

wherein R3 is hydrogen or has the same meaning as in formula I, in the presence of hydrogenation-dehydrogenation catalysts at pressures of up to 5 atm, preferably in the range of 30 atmospheric pressure, and temperatures of 160 to 230 ° C., characterized in that the liquid alcohol and / or aldehyde of the formula II or III is reacted in the presence of cobalt and / or copper chromium oxide catalysts with a gaseous mixture containing hydrogen and an amine 35 of the formula IV, the amine content of the gas mixture being 1 to 20 % By volume, preferably 3 to 10% by volume, removes the water formed in the reaction from the exhaust gas and continuously recirculates the exhaust gas back into the liquid alcohol or aldehyde.

40 The reaction of alcohols with ammonia, primary and secondary amines to the correspondingly substituted primary, secondary and tertiary amines in the presence of hydrogenation-dehydrogenation catalysts and optionally also hydrogen is known (see Houben-Weyl, Vol. 11/1, pp. 126ff .). 45 Depending on the physical state of the alcohol or amine, it is possible to work under pressure or under pressure in the gas or liquid phase.

US Pat. No. 2,953,601 describes the unpressurized reaction of alcohols (for example isooctanol) with ammonia. However, the aminolysis proceeds in a disordered manner, i.e. it leads to a mixture of primary, secondary and tertiary amines with a high proportion of foreign by-products.

According to US Pat. No. 3,223,734, preferably tertiary amines of the type claimed are obtained by reacting primary and secondary amines with alcohols in the presence of hydrogenation-dehydrogenation catalysts at temperatures of 150 to 230 ° C. The resultant during the reaction Water is removed from the process. The main difference compared to the present invention is that 60 works without hydrogen and with Raney nickel as a catalyst. This creates significant amounts of undesirable condensation and by-products, which reduces the yield. In examples 17 and 18 of the US patent, dodecanol and hydrogenated tallow alcohol in the presence of 65 Raney nickel with large excesses of dimethylamine or methylamine becomes tertiary dimethyldodecylamine (69.5%) or tertiary di (tallow alkyl) methylamine (79.1%) implemented.

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However, the reworking of the examples of the US patent showed that the two tertiary amines mentioned still contain considerable amounts of other tertiary amines. This fact is based on the fact that the dimethyl and methyl amines used in the presence of Raney nickel and the like. a. in monomethyl or. Disproportionate dimethylamine. This then produces other tertiary amines than expected, but the yield of the tertiary amines shown appears to be excessive.

No statement is made about the remaining portion of the reaction products of Examples 17 and 18 of US Pat. The cited reworking of the examples showed that

that in addition to the already mentioned abnormal tertiary amines, it was also primary and secondary amines as well as highly condensed by-products.

For large-scale production of, for example, long-chain tertiary dimethylalkylamines or tertiary methyldialkylamines, the process of US Pat. No. 3,223,734, apart from the low yields, is also unsuitable because these tertiary amines produced do not have the required degrees of purity.

The aforementioned disadvantages of US Pat. No. 3,223,734 could be eliminated by using cobalt and copper chromite catalysts and by using large amounts of hydrogen. In contrast to nickel contacts, the cobalt and copper chromium oxide catalysts do not disadvantageously disproportionate and decompose both the primary and secondary amines used and the tertiary amines produced.

Finally, it is shown in DE-OS 1 493 781 that longer-chain primary alcohols also react with dimethylamine in a largely ordered manner to give dimethylalkylamines (see experiments 2 and 4 in Table III). However, the sales achieved are absolutely unsatisfactory with regard to a large-scale process.

It has therefore also been attempted to react the corresponding alkyl halides with dimethylamine instead of the alcohols. However, these starting substances are generally not as easily accessible as the corresponding alcohols, and are therefore also more expensive. Unwanted quaternary ammonium compounds can also occur as by-products in aminolysis. The acids formed during the reaction (e.g. HCl) have to be recovered or neutralized, which - especially with regard to wastewater problems - causes additional costs.

The present invention was therefore based on the task of using the known aminolysis to develop a process for the economical production of tertiary amines which delivers high yields of these amines with virtually complete conversions.

The object was achieved in that the alcohol and / or the aldehyde with the aid of cobalt or copper chromium oxide catalysts at normal pressure or slightly elevated pressure to 5 atmospheres and temperatures from 160 to 230 ° C. with short-chain primary and secondary amines Formula IV, which contains at least one methyl group, is reacted in a mixture with preferably large amounts of hydrogen in the liquid phase, the amine content of the gas mixture being 1 to 20% by volume, the water formed in the reaction being discharged with the gas stream and removed from it and then continuously recirculates the gas mixture consisting of amine and hydrogen, if necessary after replacing part of it with fresh gas, into the process.

In this way, tertiary amines can be obtained in yields of up to 95% and a degree of purity of 98 to 100% with a conversion of over 99% of the alcohols used. The simultaneous occurrence of foreign by-products

- created by self-condensation of the intermediate (or deliberately implemented) aldehydes - is low and can be kept below 5% under optimal reaction conditions. They remain in the distillation of the amines and can therefore be easily removed.

To carry out the process according to the invention, the respective alcohol to be reacted is generally mixed with 1 to in a heatable stirred tank which is provided with a device for circulating the amine-hydrogen mixture and for removing the water of reaction 10% by weight, preferably 3 to 5% by weight, of catalyst are initially introduced. With vigorous stirring and passing through an amine-hydrogen mixture in which the amine content is to be 1 to 20% by volume, preferably 3 to 10% by volume, 15, the kettle content is raised as quickly as possible to 160 to 230 ° C., preferably 190 to 210 ° C, heated in order to suppress the formation of by-products, which occurs particularly at lower temperatures, and to be able to drive off the water formed as quantitatively as possible from the start. This is done in a manner known per se by stripping over a thermostatted cooler; entrained product, such as alcohol or already formed tertiary amine, is returned to the reaction vessel via a separator. For thorough mixing of the reaction components, which is essential for the success of the reaction, in addition to intensive stirring, the circulation of the reaction product with the aid of an externally installed circulation pump is advantageous. The amount of gas required for one mole of the respective alcohol is advantageously 50 to 1501 / h or 150 to 6001 / kg of alcohol. Even larger amounts of gas are conducive to shortening the reaction time and reducing the formation of by-products, but they are no longer economical. Such large amounts of gas, as are necessary for the method according to the invention, are advantageously continuously circulated by installing a blower. Since small amounts of gaseous by-products (hydrocarbons, carbon monoxide) are formed in the course of the process and up to 1% of the amine used is decomposed, it is advantageous to replace part of the gas with fresh gas if the cycle gas is used continuously. The progress of the reaction can be easily monitored using the water formed. When no more water separates, the reaction is complete. While due to the reaction equation

. R- OH + H, C - N -R0 »R- - N - CH,

1 3 I 2 1 | 3rd

H R2

Ri = long alkyl 50 R2 = H or short alkyl it was to be expected that the higher the concentration of amine in the circulating gas mixture, the faster the reaction in the desired sense, it was surprisingly found that the best results then be obtained when the amine concentration in the gas mixture is as low as possible. The lower limit of the amine concentration is given by the fact that the amount of amine in the circulating gas for the reaction according to the present invention is dimensioned at least such that no amine deficiency occurs; this would promote the formation of foreign by-products and extend the reaction time. The risk of an amine deficit can be compensated for by increasing circulating gas quantities, since more amine is thus offered in the unit of time. The by-product formation increases with a strongly increasing amine concentration in the cycle gas. The hydrogen content in the cycle gas (80 to 95 vol.%) Can only up to 30 to 40 vol.% By inert gases, such as. B. nitrogen or me-

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than, to be replaced. It follows that the hydrogen is of crucial importance for the reaction mechanism of the method according to the invention, although it does not appear in the gross equation cited. This finding is in direct contrast to the information in US Pat. No. 3,223,734, column 4, lines 30-45, where it is expressly noted that the hydrogen is used to drive off the water of reaction and by inert gases (such as nitrogen ) or can be replaced by other techniques (such as, for example, azeotropic distillation or application of vacuum - column 4, second paragraph and claim 11).

Likewise, the finding is in contrast to the explanations in DE-OS 1 493 781, page 8, third paragraph, where it is pointed out that when alcohols are reacted, the yield of tertiary amine can be increased in the presence of small amounts of hydrogen; however, it is expressly emphasized that for 1 mole of alcohol, lV3 moles of hydrogen are completely sufficient, while in the process according to the invention at least 20 times the amount of hydrogen is required. The high hydrogen requirement is decisive for the claimed process and could not be derived from US Pat. No. 3,223,734 or from DE-OS 1 493 781.

After the reaction has ended, the catalyst is separated from the product via a suitable filter device (rotary disk filter, decanter) and the tertiary amines formed are distilled off to remove the by-products, which are then obtained in very pure form. The catalyst can be used repeatedly, interim losses - about 0.2% per batch - are replaced. This results in a catalyst consumption of less than 0.3%. A major advantage for the economics of the process is that the use of amines corresponds approximately to the theory; Unavoidable amine losses in the exhaust gas or by dissolving in the separated water of reaction do not play a role in the low amine concentration in the cycle gas. As a result, there are practically no exhaust gas or wastewater problems with this method.

Similar to the long-chain alcohols, the corresponding aldehydes react using the process according to the invention and give equally good yields. When used, the process must be modified in that the respective aldehyde must not be introduced in its entirety, but may only be fed gradually (continuously) to the reaction vessel, the metering rate roughly corresponding to the reaction rate in the aminolysis of the alcohols. To do this, it is necessary to present the end product at the start of the reaction. If the aldehyde is used all at once, up to 60% of by-products are formed. This variant of the process according to the invention can be of technical importance when using easily accessible aldehydes (for example those from oxosynthesis). The previous assumption that the aminolysis proceeds via the corresponding aldehydes in the course of primary dehydrogenation has found support in practice.

As just shown in the aminolysis of the aldehydes, the aminolysis of the alcohols to tertiary amines can also be carried out continuously. Since the circulating gas volume and gas composition are kept constant from start to finish, in the simplest embodiment the stirred tank already described at the beginning can be used with the following additional devices: a metering pump for introducing the alcohol and small amounts of catalyst, product removal from the stirred tank via a filter or a decanter to keep the reaction volume constant and a device for discharging small amounts of catalyst. Of course, other embodiments of the continuous driving style are possible, such as. B. one in which several reaction vessels are connected in series (cascade).

Starting materials in the sense of the invention are straight-chain and branched, saturated and unsaturated aliphatic 5 primary alcohols of the formula II, for example n-octyl alcohol, lauryl alcohol, myristyl alcohol and mixtures of such alcohols, and also the alcohols obtained from ethylene by the Ziegler process and mixtures thereof , furthermore isooctyl alcohol, isotridecyl alcohol (obtained from oxosynthesis with the help of triisobutylene). Instead of the alcohols, the corresponding aldehydes can also be used, such as. B. lauryl aldehyde or aldehydes, as they occur after the oxo process from olefins. Mixtures of alcohols and aldehydes can also be used. 15 Primary and secondary amines of the formula IV, such as, for example, methylamine, methylethylamine, methylbutylamine, preferably dimethylamine, are suitable as amines in the context of the invention.

Cobalt and copper chromium oxide 20 catalysts are used alone or in a mixture as catalysts. Catalysts which contain copper chromite and additionally copper oxide in excess are particularly suitable. By adding metal oxides of the first and second main group of the periodic table, such as. As potassium, magnesium 25 or barium, the life of the catalysts is increased. Contact with 41% copper, 31% chromium and 0.3% barium (corresponding to 69% copper chromite, 28% copper oxide and 0.5% barium oxide) is very suitable. As the copper chromium oxide content decreases, the effectiveness of the catalysts 30 decreases. If the metal oxides in concentrated form by known methods on inert supports, such as. B. alumina or silica gel applied can be used, in particular, carrier-free full contacts. The catalysts mentioned are excellent dehydrogenation contacts with reduced hydrogenation activity at a higher temperature (180 to 220 ° C.). The primary and secondary amines with at least one methyl group on the nitrogen atom used according to the invention are hardly attacked by these catalysts even at higher temperatures 40 - the conversion to tertiary amines is therefore orderly, with only a small proportion of by-products. Nickel catalysts are not suitable for the process according to the invention, since the amines disproportionate and decompose under the chosen reaction conditions.

The tertiary amines produced according to the invention can be used as intermediates for a wide variety of syntheses.

They are particularly often used for quaternization with methyl chloride and other alkylating agents and then give quaternary ammonium salts. These in turn are used as disinfectants and algicides as well as retarders in textile dyeing. A large area of application of the quaternary 55 ammonium salts produced from the tertiary amines is their use as fabric softener.

Mention should also be made of the conversion of the tertiary amines with hydrogen superoxide into amine oxides, which have found a large area of use for household cleaning agents, particularly in combination with anion-active components. In addition, the claimed tertiary amines can also be used directly for the so-called liquid extraction of certain metal ions from aqueous solutions.

65 Example 1

The reaction was carried out in the apparatus shown in the figure. The apparatus consists of a 100 liter stirred tank 1 with a packed column 2,

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a circulating gas blower 3 and a circulating gas line 4 for circulating the gaseous amines, hydrogen and possibly inert gases, a cooler 5, a separator 6 for water and volatile organic components, and feeds for the amine 7, H2 8 and optionally N2 9 (as a detergent or optionally, gas additive) and from an exhaust gas line 10. The boiler is heated and cooled via the jacket 11. From the separator 6, a line 12 leads back to the boiler 1, via which the organic phase 14 separated from the separated aqueous phase 13 can be returned.

500 kg (2.68 kilomoles) of dodecanol-1 and 20 kg of copper chromite full contact (41% Cu, 31% Cr, 0.3% Ba) were introduced into the heated Im3 stirred tank 1. The apparatus was flushed over 9 with nitrogen, heated with stirring, the nitrogen was displaced over 8 with hydrogen, 3 200 Nm 3 / h of hydrogen were circulated by turning on the cycle gas blower and the metering in of dimethylamine over 7 was started at 150 ° C. The reaction started at 150 ° C and was optimal at 200 to 210 ° C, recognizable by the elimination of water. The dimethyl concentration in the cycle gas was adjusted to 5 to 7% by volume by metering and measuring devices. Since small amounts of gaseous by-products are formed during the reaction, 10% of the free circulating gas volume (1 m3) was continuously passed over 10 every hour and replaced by fresh gas. The overpressure in the apparatus was 0.2 to 0.4 bar. A first separation between the amine-alcohol mixture on the one hand and the water of reaction on the other hand occurred in column 2 with cooler 5 mounted on the reaction vessel. In the separator 6, the organic phase was separated from the aqueous phase and the (upper) organic phase was recirculated to the column.

After 6 hours the reaction was complete and 53 liters of aqueous phase had separated out. After cooling to 100 ° C and flushing with nitrogen, filter off the contact via a turntable filter. 553 kg of crude amine with an amine number of 44.7 (theory: 46.8) were obtained. The alcohol had converted to 99.7%, primary and secondary amines were less than 1.5% in the crude product. Only 2.4% of the theory of dimethylamine was used for the implementation. In order to separate the dimethyldodecylamine produced from high-boiling by-products, it was distilled off in vacuo without fractionation. The yield of pure product was 9.25%, based on the alcohol used, with a degree of purity of 98%.

Example 2

500 kg of dodecanol-1 were reacted in the same apparatus as in Example 1 under the same conditions as described there. In addition, however, the reaction product was pumped over by pulling it off at the bottom of the reaction vessel and releasing it into the gas phase of the container. The output of the P2 circulation pump was designed so that the entire boiler contents circulated six times an hour. As a result of better mixing, the reaction time was reduced to 5.2 hours. The alcohol had converted to 99.8%. After distillation, 98.5% dimethyldodecylamine was obtained with a total yield of 93.5%, based on the alcohol used, and 94.6%, based on the dimethylamine used.

Example 3 (a-c)

In order to demonstrate the influence of the dimethylamine concentration in the cycle gas on the yield of the desired product and thus the economy of the process, the following attempts were made:

a) 50 kg (240 mol) of synthetic alcohol with a chain distribution: 33% C12, 64% C14 and 3% Cio and C16 and 2 in a 100 liter VA stirred kettle with the same additional equipment as on the apparatus as in Example 1 kg of copper chromite contact (as in Example 1) submitted. After purging with nitrogen, the kettle was heated to 160 ° C. in half an hour while stirring and circulating hydrogen and then the addition of dimethylamine was started. The circulating gas volume was 12 m3 / h and the dimethylamine concentration in the circulating gas was 5 to Ì0 vol.%. 101 of the cycle gas were replaced with fresh gas per hour. After 7 hours and a reaction temperature of 205 to 210 ° C. and elimination of 4.7 l of water, the reaction was complete. In the subsequent vacuum distillation of the crude amine, 5.2% residue remained. The distilled dimethyl-Cio_i6-alkylamine still contained 0.4% alcohol, 0.6% primary and secondary amine and 1.1% non-amine. The overall yield was 91.3% on alcohol and 93.4% on dimethylamine used.

b) The amounts and procedure corresponded to the example under a), with the difference that the concentration of dimethylamine in the circuit was 15 to 20% by volume. The reaction was complete after about 8 hours and 5.4 l of water had formed. After working up, 12.4% residue remained in the kettle. The yield of 97.5% dimethyl-C10_i6-al-. Alkylamine was 83.5% based on alcohol and 80.7% based on the dimethylamine used.

c) The amounts and procedure corresponded to example b), with the difference that the dimethylamine concentration in the cycle gas was set at 35 to 40% by volume. After 7.5 hours the reaction was complete and 6.41 water had separated out. The overall yield of 98% dimethyl-C10_i6-alkylamine was only 73.8%, based on alcohol, and only 68.5% on the dimethylamine used.

The falling yields in Examples 3 a) to c) are due to self-condensation of the intermediate aldehyde. With increasing dimethylamine concentration in the cycle gas, the dimethylamine losses in the water of reaction increase.

Example 4 (a-e)

In order to test the influence of hydrogen on the mechanism of the process, the following series of experiments was carried out: 1 mol of dodecanol-1 and. Were in a laboratory apparatus consisting of a 1 liter stirred flask with thermostatted cooler, connected condenser and separator for separating the water of reaction 4% copper ferrite catalyst (as in Example 1) presented. The stirrer was turned on and the mixture in the flask was heated to 100 ° C. while passing nitrogen through it. From steel bottles, various mixtures of hydrogen, dimethylamine and nitrogen were passed through the reaction product via coolers into the fume cupboard via capillaries and a dry gas meter. The amount of the gas mixture was kept constant at 1001 and a reaction temperature of 210 ° C. was set in the flask. The results for various gas compositions can be found in the table below:

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attempt

Gas composition

Reaction

Amine

prim. + sec.

Distillation

h2

DMA *

n2

time number

Amine residue

(1)

(1)

(1)

Hours

(% By weight)

(%)

4a

105

5

_

6.5

44.1

1.5

5.1

4b

95

5

10th

7.5

43.8

1.5

6.2

4c

75

5

30th

7.7

43.4

1.5

7.3

4d

55

5

50

8th

39.5

1.5

17.8

4e

85

5

50

7.5

43.1

1.5

7.6

* DMA = dimethylamine

This table shows that only 30 to 40% of the hydrogen can be replaced by inert gases (e.g. nitrogen).

Example 5

In order to test the influence of various catalysts for the process, the following test series were carried out: 300 g (1.43 moles) of synthetic alcohol with the chain distribution: 33% Ci2, 64% Ci4 and 3% C10 and C16 were used in the laboratory apparatus described in Example 4 , and 15 g 15 of the respective catalyst presented. 1101 of a gas mixture of 90 to 95% by volume of hydrogen and 5 to 10% by volume of dimethylamine were passed through the mixture at 208 to 210 ° C. with stirring and the water of reaction formed was condensed out. The results with different catalysts under otherwise identical reaction conditions are summarized in the following table.

catalyst

Reaction time tert-amine

alcohol

Distillation

Amine number

Art

(Hours)

Equiv. %

% By weight

residue (% by weight)

Copper chromite

number 1

6

99.8

0.5

4.8

41.0

Copper chromite

No. 2

6.5

99.7

0.5

5.6

40.4

Copper chromite

No. 3

8th-

98.6

0.9

11.5

39.0

Copper chromite

No. 4

7-

99.3

0.5

5.3

40.8

Copper chromite

No. 5

7-

99.9

0.5

8.3

39.3

Raney nickel

5.5

76.6

0.5

41.7

28.5

45% by weight cobalt

on diatomaceous earth

6-

93.4

0.5

15.8

37.8

Specification of copper chromite catalysts:

catalyst

Copper (%)

Chrome (%)

Barium (%)

No. 1 No. 2 No. 3 No. 4 No. 5

40.5

31.6 30.3 35.2 41-

31-

33.4

30.5 30.0 30-

0.3 9.4

9.1

8.2

So while very similar results are obtained with different copper chromite catalysts, Rany nickel behaves completely differently - 40 to 50% by-products and larger amounts of primary and secondary amines are formed. Cobalt contacts are similar to copper chromite catalysts, but give somewhat poorer results with regard to the formation of tertiary amines and the distillation yield.

Example 6

50 kg of isotridecyl alcohol (a mixture of branched Ci3 alcohols from the oxosynthesis of Ci2-01efins) with the OH number 281 and 1.5 kg of copper chromite catalyst as in Example 1 were placed in a 100 liter reaction kettle as in Example 3 and rapidly heated while stirring and passing hydrogen cycle gas through. The amount of circulating gas was 18 Nm3 / h and the dimethylamine concentration in

Cycle gas 5 to 6% by volume; 10% of the cycle gas volume was replaced by fresh gas every hour. 1 hour after the start of heating, a reaction temperature of 210 ° C. was reached and the reaction was ended 6 hours later. 4.71 amine-containing water had separated out. With 99.5% conversion, the yield of dimethylisotridecylamine, based on alcohol, was 92.5% with a degree of purity of 98.5%.

Example 7

Analogously to Example 5, 50 kg of isooctyl alcohol (a mixture of branched Cs alcohols, obtained from the oxythesis of pure heptenes via co-dimerization of butene and propylene) were reacted with dimethylamine in the presence of copper chromite catalyst from Example 1. Because of the low boiling point of isooctanol (180-185 ° C), the pressure was slightly increased (3 to 4 bar). The reaction temperature was 195 to 200 ° C, the circulating gas amount 20 Nm3 / h and 60 the dimethylamine concentration in the circulating gas 6 to 8 vol.%. Product and water were removed from a side branch of the column, separated in a separator and the organic phase was taken up again in the reaction vessel. After 8 hours, the reaction, in which 7.8 1 65 of amine-containing water had separated, had ended.

The dimethyl-isooctylamine was obtained in a total yield of 91.8%, based on the alcohol, and was 98.5 equivalent% of tertiary amine.

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Example 8

Analogously to Example 5, 50 kg of ocenol (oleyl alcohol having an iodine number of 92) were reacted with 2 kg of catalyst from Example 1 with dimethylamine. The reaction temperature was 210 ° C, the circulating gas amount 14 Nm3 / h and the amine concentration in the circulating gas 4 to 6 vol.%; 10% of the cycle gas volume was replaced by fresh gas every hour. The reaction was complete after 5.5 hours; 3 l of water had separated out. The pure dimethyloleylamine was obtained in 93.4% yield by distillation. The analysis showed

Oleyl alcohol: 0.5% by weight

tertiary amine: 99 equivalent% non-amine proportions: 0.1% by weight

Iodine number 83

Example 9

Stenol (Cig_24 alcohol with the composition C18 = 10%, C20 = 55 to 60%, C22 = 25 to 30%, C24 = 0 to 5% with the OH number 200) gives the same procedure as in Example 8 in 4.5 hours of dimethyl-C18_24-alkylamine with 92.3% yield in 98% purity.

Example 10

500 g of methyldidecylamine and 15 g of catalyst as in Example 1 were placed in a laboratory apparatus as described in Example 4. In addition to the apparatus described in Example 4, the reaction flask was connected to a metering pump via a product line, so that it was possible to add a defined amount of product in defined time intervals during the reaction.

The flask was flushed with nitrogen, the contents were heated to 210 ° C. with stirring and a mixture of 100 l of hydrogen and 5 l of monomethylamine / h was passed through. 60 g hourly decanol-1 were continuously metered in via the metering pump.

Analysis of hourly samples showed that the mixture remained unchanged in composition, containing 85 equivalent% methyldidecylamine and approximately 15 equivalent% methyldecylamine, while the alcohol had practically completely reacted. After 5 hours and further addition of 2 mol of decanol-1, 32.8 ml of water had separated out. In order to completely convert the secondary methyldecylamine formed, the methylamine feed was shut off and the calculated amount of decanol-1 was metered in under pure hydrogen. The reaction was complete after a total of 7 hours; a total of 35.5 ml of water had separated out. The crude amine was distilled, leaving 6.1% residue. The overall yield of methyldidecylamine, based on the alcohol used, was 92.4% with a purity of the product of 98%.

Example 11

In an analogous manner as in Example 10, stearyl alcohol was reacted with monomethylamine to give methyldistearylamine. In addition, the reaction gas, consisting of 1001 hydrogen and 5 l monomethylamine, was circulated via a gas pump and amine consumed during the reaction was continuously metered in by means of mercury immersion. The pressure in the apparatus was kept constant. After 2 moles of stearyl alcohols (90 g / h) had been added continuously over the course of 6 hours, the amine addition was stopped. 33.8 ml of water had separated out. The reaction was completed by adding the calculated amount of stearyl alcohol. After the crude product was distilled, 4.1% more condensed by-products remained. The yield of methyl distearylamine was 92.4% with a product purity of 98.5%.

Example 12

400 g of dimethyldodecylamine and 15 g of the catalyst from Example 1 were placed in a laboratory apparatus as described in Example 10. The apparatus was flushed with nitrogen, the contents were heated with stirring, a mixture of 101 dimethylamine and 180 l of hydrogen was passed through per hour and the addition of 50 g / h of lauryl aldehyde (96%) was started at 210 ° C. using a microdosing pump . The continuous addition of aldehyde corresponded to a constant elimination of water of 4.7 ml / h. The analysis of samples taken every hour showed that the amine number also remained unchanged at 44 to 44.5. After 369 g (2 mol) of lauryl aldehyde had been metered in in about 7 hours, the reaction was stopped. The yellow colored reaction product with an amine number of

44.4 had the following composition after analysis:

tert-amine 99% by weight

Lauryl aldehyde 0.1% by weight

Dodecanol-1 0.5% by weight

In addition, 8.3% by weight of higher condensed by-products were formed. After the distillation, a 99% dimethyldodecylamine with an amine number of 46.1 (Th. 46.9) was in

Obtained 88.5% yield.

A parallel approach with dodecanol-1 instead of the aldehyde was analogous. Here the yield of dimethyldodecylamine was 92%.

Example 13 (comparison to Example 12)

The reaction of laurylaldehyde with dimethylamine was carried out in the same apparatus as in Example 10, with the difference that the aldehyde was not metered in gradually, but was used all at once. After purging the apparatus with nitrogen, the mixture was heated to 210 ° C. while stirring and introducing 1801 / h of hydrogen, and the addition of 101 / h of dimethylamine was started at this temperature. After a running time of 6 hours with simultaneous elimination of 35 ml of water, the reaction was complete. The dark brown colored reaction product with an amine number of 33.2 gave 59% residue in the distillation. The yield of dimethyldodecylamine was only 37%.

Example 14

300 g (1.6 mol) of dodecanol and 12 g of a cobalt catalyst (45% cobalt on kieselguhr) were placed in a laboratory apparatus of the type described in Example 4. The mixture in the flask was heated to 100 ° C. while stirring and passing nitrogen through, the nitrogen was displaced by hydrogen and the addition of dimethylamine was started at an internal temperature of 195 ° C. The hourly amount of gas passed through the reaction product was 1001 hydrogen and 5 l dimethylamine, the reaction temperature 195 to 196 ° C. After 8 hours reaction time and separation of 17.5 ml water, the reaction was stopped and the catalyst was filtered off. After distillation, dimethyldodecylamine was obtained with a purity of 94.7%; the residual alcohol content was below 0.1%.

Example 15

In a laboratory apparatus as described in Example 10, 400 g of methyl-n-butyl-n-decyl-amine having an amine number of 44.8 and 15 g of catalyst of the type described in Example 1 were placed in a 2 liter glass flask. After purging the apparatus with nitrogen and heating to 210 ° C. with stirring, a gas mixture of 1001 hydrogen per hour (from a bomb) and 10 1 methyl-n-butylamine (via an evaporator) was passed through the product and then via a thermostatic

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622 237

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based cooler (60 ° C) passed into the fume cupboard; at the same time, the continuous addition of 60 g / h decanol was started via a metering pump. The addition corresponded to a constant elimination of water of 5.6 ml / h. Analysis of hourly samples showed that the amine number (42.6) remained almost unchanged. After about 6 hours, the addition of alcohol was stopped, the gas mixture was replaced by nitrogen and the mixture was cooled to 100.degree. a total of 34.5 ml of water had separated out. The crude amine was filtered off from the catalyst and distilled, leaving 5.2% by weight of residue remaining. The overall yield of methyl-n-butyl-n-decyl-amine was 93.1% with a purity of 97.5%.

1 sheet of drawings

Claims (7)

622 237 2. The method according to claim 1, characterized in that one carries out the reaction at atmospheric pressure. 2nd PATENT CLAIMS 1. Process for the preparation of tertiary aliphatic amines of the formula I " / R2 R1 ~ CH2 "N ' (I), R- wherein Ri is a straight-chain or branched, saturated or unsaturated aliphatic radical having 7 to 23 carbon atoms, R2 = Ri-CH2 or CH3 and R3 = CH3 for R2 = Rj-CH2 or R3 = CH3, C2Hs, C3H7 or C4H9 for R2 = CH3 , by reacting aliphatic alcohols and / or aldehydes of the formulas II and / or III Rj_Ch2-OH (II) and / or R % H (HI), 0 wherein Ri has the same meaning as in formula I, with primary or secondary amines of formula IV H - N CH- wherein R3 is hydrogen or has the same meaning as in formula I, in the presence of hydrogenation-dehydrogenation catalysts at pressures of up to 5 atmospheres and temperatures of 160 to 230 ° C., characterized in that the liquid alcohol and / or aldehyde of the formula II or III in the presence of cobalt and / or copper chromium oxide catalysts with a gaseous mixture containing hydrogen and an amine of the formula IV, the amine content of the gas mixture being 1 to 20% by volume, which is the result of the reaction Water formed is removed from the exhaust gas and the exhaust gas is continuously recycled back into the liquid alcohol and / or aldehyde. 3. The method according to claim 1, characterized in that one uses a gaseous mixture whose amine content is 3 to 10 vol.%. 4. The method according to claim 1, characterized in that a part of the exhaust gas is replaced by a mixture of hydrogen and an amine of formula IV before being returned to the liquid phase. 5. The method according to claim 1, characterized in that 30 to 40 vol.% Of the hydrogen is replaced by inert gas. 6. Process according to Claims 1 and 4, characterized in that the reaction is carried out in whole or in part continuously and the end product of the reaction is initially introduced. 7. Process according to claims 1 to 5, characterized in that mixtures of alcohols and aldehydes are used.