JPH0249295B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a process for producing tertiary amines having long chain alkyl groups, and more particularly to long chain olefins, carbon monoxide, hydrogen and primary or secondary amines. The present invention relates to a method for producing a tertiary amine having one or two long-chain alkyl groups by reacting it with an amine.

Tertiary amines with long-chain alkyl groups are converted into various derivatives such as quaternary ammonium salts and amine oxides, and depending on their structure, they have various uses such as detergents, antistatic agents, and fabric softeners. It is a useful substance with many properties, and currently most of it is commercially produced from natural fatty acids such as coconut oil, palm oil, and beef tallow.

PRIOR ART Existing methods for producing tertiary amines from natural fatty acids include a step of synthesizing fatty nitriles by high-temperature reaction of fatty acids and ammonia, a step of converting fatty nitriles into primary or secondary amines by hydrogenation, and a first step. It consists of a step of converting a secondary or secondary amine into a tertiary amine by reductive N-methylation, or a step of converting it into a tertiary amine containing a hydroxyalkyl group by addition of alkylene oxide, and involves many complicated steps. Requires.

On the other hand, by subjecting a higher alcohol to a so-called aminolysis reaction with a lower alkyl group-containing secondary amine such as dimethylamine under hydrogen pressure in the presence of a hydrogenation catalyst, long-chain alkyldimethylamine can be produced in good yield. It is also possible to convert to various tertiary amines, as described in Tetrahedron Letters, Vol. 22,
It is described in detail on pages 1937-1938 (1977). Alternatively, it is also known to convert higher alcohols to tertiary amines containing long-chain alkyl groups via chlorides.

However, methods using these higher alcohols as starting materials require that the higher alcohols used as raw materials are more expensive than fatty acids, and the latter method, which uses chlorides, requires the use of corrosive substances such as chlorine. There are problems such as.

At the same time, in methods using these higher alcohols as starting materials, tertiary amines containing hydroxyl groups, which are in great demand among tertiary amines, such as long-chain alkyl bis(2-hydroxyethyl)
Not suitable for producing amines, etc. This is because, in the above reaction involving hydroxyl groups, not only the hydroxyl groups of the higher alcohol, but also the hydroxyl groups of the lower amines that are the raw materials to be reacted with, and the tertiary amines that are the target products are also involved in the reaction. This is because it is extremely difficult to obtain the desired product in good yield.

On the other hand, it is also known to synthesize tertiary amines from long-chain olefins, carbon monoxide, hydrogen, and primary or secondary amines.
Publication No. 9527 discloses a one-step synthesis method for tertiary amines from olefins, carbon monoxide, hydrogen, and secondary amines using a catalyst containing a complex compound consisting of tri(hydrocarbyl)phosphine and cobalt carbonyl. . However, this method produces a large amount of alcohol as a by-product and is not necessarily effective as a method for producing the desired tertiary amine.

Helvetica Chimica Acta.54 (1971) 1440
-1445 and US Pat. No. 3,947,458 disclose a method for producing amines from olefins, carbon monoxide, water, and nitrogen-containing compounds by using a catalyst consisting of iron pentacarbonyl and a rhodium compound. Although this method has a fairly good amine yield, it does not use a cheap mixture of hydrogen and carbon monoxide as a raw material gas, but requires pure carbon monoxide, and requires recovery of expensive rhodium compounds. is necessary.

Japanese Patent Publication No. 52-38527 describes the reaction of olefin, carbon monoxide, hydrogen, and secondary amine in the presence of a group metal complex having a ligand whose electron-donating atom is oxygen, nitrogen, or sulfur. A method for producing tertiary amines is disclosed. Although this method also has a very good yield of the target amine, the recovery and reuse of expensive group metals such as rhodium and ruthenium, which are used in considerable amounts, poses a problem for industrial use. There is no mention of anything.

Purpose of the Invention Previously, the present inventors carried out the reaction by using specific alcohols as a solvent to form an upper layer containing the reaction solution as a main component of an amine containing a long-chain alkyl group;
It was discovered that phase separation could be achieved between the lower layer and the lower layer, which mainly consists of the solvent containing most of the catalyst used.
It was proposed as No. 201986 (Japanese Unexamined Patent Publication No. 64-12263).

The present invention is a further development of the above-mentioned invention, and even when phase separation does not actually occur or is difficult to occur, and it takes a long time to reach complete phase separation, the produced amine layer and the catalyst-containing solvent can be separated from each other. The purpose is to facilitate separation into layers.

One way to promote phase separation is to add water into the reaction zone, which can make the solvent layer more polar and easier to separate from the formed amine layer; Addition of water significantly inhibits the conversion reaction of long-chain olefins to long-chain alkyl tertiary amines, reducing the olefin conversion rate, increasing the concentration of intermediate aldehydes in the reaction zone, and producing heavy substances. This results in an increase in the amount of by-products, etc., and as a result, the selectivity for the desired amine decreases significantly.

Summary of the Invention As a result of intensive study on a method to satisfy both of these two contradictory conditions, it was found that by carrying out the reaction and phase separation by adding water separately, the original purpose could be achieved without adversely affecting the reaction. The present invention was completed after discovering what could be achieved.

That is, the present invention combines a long-chain olefin with 6 to 20 carbon atoms, carbon monoxide, hydrogen, and a primary or secondary amine in the presence of a catalyst mainly containing a compound containing rhodium and/or ruthenium. Below, monohydric alcohols with 1 to 3 carbon atoms, dihydric alcohols with 2 to 6 carbon atoms, and 3 carbon atoms as solvents.
- 6 trihydric alcohols and intermolecular dehydration condensates of dihydric or trihydric alcohols having 2 to 3 carbon atoms. In the method for producing tertiary amines by separating tertiary amines, water is added to the reaction product to form a reaction product, which comprises an amine layer containing the tertiary amine and an aqueous solution layer containing the catalyst. An object of the present invention is to provide a method for producing tertiary amines, which is characterized by causing phase separation.

Detailed Description of the Invention (Catalyst) The catalyst used in the present invention is a rhodium and/or ruthenium compound, and is used in the form of a halide, nitrate, halocarbonyl, carbonyl complex, or the like.

Specifically, rhodium chloride, rhodium nitrate, rhodium bromide, rhodium iodide, chlorodicarbonyl rhodium dimer, rhodium carbonyl, ruthenium chloride, ruthenium nitrate, ruthenium bromide, ruthenium iodide, dichlorotricarbonyl ruthenium dimer. , ruthenium carbonyl, and the like.

The amount of these catalysts used is 100 to 100% of the raw material olefin.
The range is 1 mole of the catalyst per 20000 moles,
Particularly preferably, the amount of the catalyst is 1 mole per 500 to 1000 moles of raw material olefin.

(Raw material olefin) The raw material long-chain olefin used in the present invention is an olefinic unsaturated compound having a hydrocarbon skeleton, and those having a linear hydrocarbon group and 6 to 20 carbon atoms are particularly suitable. There is. Such linear olefins include, for example, ethylene oligomers having terminal double bonds obtained by low polymerization of ethylene, catalytic dehydrogenation of linear hydrocarbons obtained from kerosene and gas oil fractions, or ethylene oligomers etc. Examples include linear olefins having a double bond inside the molecule obtained by isomerization and disproportionation of α-olefins.

(Solvent) The solvent used in the method of the present invention has 1 to 1 carbon atoms.
3 Monohydric alcohols such as methanol, ethanol, n-propanol and isopropanol Dihydric alcohols having 2 to 6 carbon atoms such as ethylene glycol, propylene glycol, butadiol, pentanediol, neopentyl glycol, etc. Trihydric alcohols having 3 to 6 carbon atoms Alcohols such as glycerin, trimethylolpropane, etc.

Alternatively, intermolecular dehydration condensates of dihydric alcohols having 2 to 3 carbon atoms, such as diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol with an average molecular weight of 2000 or less, polypropylene glycol, and ethylene oxide. A block or random copolymer of propylene oxide and propylene oxide, diglycerin which is an intermolecular dehydration condensate of glycerin, etc. can also be used.

(Raw material primary or secondary amine) The raw material amine used in the present invention is selected depending on the intended long-chain alkyl group-containing tertiary amine. Specifically, methylamine, ethylamine, n-propylamine, isopropylamine,
Primary amines such as n-butylamine, isobutylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, dimethylamine, diethylamine, diisopropylamine, di-n-butylamine, diisobutylamine, dipentylamine, dihexylamine, Secondary amines such as diheptylamine, dioctylamine, dinonylamine, and didecylamine are used.

Furthermore, the method of the present invention is particularly applicable to hydroxyl-containing primary amines such as monoethanolamine, monoisopropanolamine, mono-n-propanolamine, mono-n-butanolamine, diethanolamine, diisopropanolamine, di-n-propanol The effect is remarkable when a hydroxyl group-containing amine such as hydroxyl group-containing secondary amines such as amine and dibutanolamine is used as a raw material.

(Reaction) The reaction conditions for synthesizing the tertiary amine of the present invention are a temperature of about 70 to 240°C and a pressure of about 30 to 300 atm, particularly a temperature of 100 to 200°C and a pressure of about 60 to 200 atm.
Atmospheric pressure is preferred. The reaction pressure is substantially determined by the partial pressures of carbon monoxide and hydrogen used in the reaction, but in some cases, gases inert to the reaction such as nitrogen, helium, and methane may also be present at the same time. can not use. The hydrogen:carbon monoxide molar ratio can also be varied over a wide range, but in most cases a ratio of 1.5 to 2.0 moles of carbon monoxide per mole of hydrogen will improve olefin conversion and tertiary amine conversion. Good results are obtained in both yields.

(Addition and removal of water to the reaction solution) Addition of water to promote phase separation after the reaction and to reduce the elution of the catalyst into the generated amine layer is as follows:
The addition is usually carried out at room temperature, but in order to speed up the transfer of the catalyst and solvent to the aqueous solution layer, the addition can also be carried out at a temperature of 40 to 100°C and then cooled. This is accomplished by adding the required amount of water after the reaction and before allowing the contents to cool completely to room temperature.

There is no particular limit to the amount of water added, but since most of the water needs to be removed before being circulated into the reaction zone, it is desirable to keep the amount to the minimum necessary to facilitate phase separation. . Usually, this amount is within the range of 0.2 to 0.3 parts by weight per 10 parts by weight of the reaction solution.

If the aqueous solution layer containing the catalyst and solvent obtained in this way is recycled into the reaction zone as it is, the presence of a large amount of water will have a negative effect on the reaction, so after most of the water is removed, it is returned to the reaction zone and used as a catalyst. Reused.

Removal of water does not have to be complete and does not pose much of a problem as long as the water concentration in the reaction zone is below 5 to 10 wt%.

Although all known separation techniques can be used to remove water from such aqueous solutions containing solvents and catalysts, water can usually be removed by flash distillation under reduced pressure at a bottom temperature not exceeding 40 to 100°C. This is the simplest method.

In the case of C ₁ -C ₃ monohydric alcohols which are difficult to separate by this method, it is also possible to remove water using other methods such as membrane separation.

(Effect of the invention) According to the method of the present invention, water is added to the reactant after the completion of the reaction, and the aqueous solution layer taken out in the form of an aqueous solution containing most of the catalyst by phase separation is obtained after most of the water is removed. , can be recycled again in the reaction zone and reused as a catalyst.

In this case, the inhibition of the reaction by water is limited to when it coexists in the reaction zone, and the result is that even if the complex catalyst comes into contact with a large amount of water before and after the reaction, there is almost no adverse effect on the reaction. This could not have been expected based on conventional knowledge that water added into the reaction zone slows down the reaction rate of olefins and deteriorates catalyst performance.

In addition, the present invention is characterized in that the content after the reaction is a long chain that does not phase-separate rapidly or does not phase-separate at all into an upper layer mainly composed of the produced amine and a lower layer mainly composed of a solvent containing most of the catalyst. It also enables the recovery and reuse of valuable catalysts during the production of alkyl group-containing amines.

For example, the carbon chain length of long-chain alkyl groups becomes shorter, or amines containing especially hydroxyl groups, such as long-chain alkyl bis(2-hydroxyethyl) amines, are compatible with polar solvents such as polyhydric alcohols. The present invention enables commercially advantageous production of tertiary amines, which are difficult to phase separate.

Furthermore, even when phase separation is relatively easy, application of the present invention has the advantage that losses associated with solvent during phase separation and catalyst elution into the formed amine layer can be greatly reduced.

Experimental Examples Example 1 Polyethylene glycol with an average molecular weight of 600 containing 0.023 g of RhCl _{3.3H 2} O: 30 g, 1-dodecene 34
g, and diethanolamine: 26 g were placed in a 200 ml autoclave with electromagnetic induction stirring, and a mixture of hydrogen and carbon monoxide with a molar ratio of 1.8:1.0 was used.
The reaction was carried out at 150° C. for 2 hours under a pressure of Kg/cm ² .

After the reaction was completed, the mixture was cooled and the contents were extracted to obtain a pale green homogeneous solution without phase separation. As a result of analysis, the conversion rate of dodecene was 94% and the yield of tridecylbis(2-hydroxyethyl)amine was 72%.

Add 12g of H ₂ O to this and heat at 80°C under nitrogen atmosphere.
After stirring for 30 minutes at , upon cooling, the contents phase separated into a pale yellow upper layer and a green lower layer containing most of the catalyst. The Rh content was 1 ppm in the upper layer and was mostly present in the lower layer.

Under reduced pressure of 20 mmHg and under conditions that the pot temperature does not exceed 80°C, 8 g of water is distilled off from this lower layer, and 30 g of 1-dodecene and 24 g of diethanolamine are added to this again.
As a result of the reaction, the catalyst still had sufficient activity, and the olefin conversion was 91% and the desired amine yield was 64%.

Comparative Example 1 Polyethylene glycol with an average molecular weight of 600 containing 0.030 g of RhCl ₃ 3H ₂ O: 32 g, 1-dodecene:
10 g of water was added to 24 g of 30 g diethanolamine, and the reaction was carried out according to the method described in Example 1.

After the reaction, the contents phase-separated into a pale yellow upper layer and a green lower layer. However, as a result of compositional analysis, the olefin conversion rate was 56% and the yield of tridecylbis(2-hydroxyethyl)amine, the desired product, was only 25%. It was shown that the presence of water had a significant negative effect on the reaction.

Example 2 35 g of ethylene glycol, 28 g of 1-octene, and 23 g of diethylamine containing 0.052 g of Rh(NO ₈ ) ₂・3H ₂ O were added to a 200 ml autoclave with electromagnetic induction stirring, and hydrogen: mol of carbon monoxide was added. ratio
Under a pressure of 130Kg/cm ² using a 1.6:1.0 gas mixture,
The reaction was carried out at 140°C for 3 hours.

After the reaction, the contents phase-separated into a pale yellow upper layer and a green lower layer. Analysis of the composition of the upper layer, which contains most of the produced amine, revealed that the octene conversion rate was 98%, and the desired nonyldiethylamine was 83%. The yield was high.

At this time, the Rh concentration in the upper layer was 5 ppm.

Add 15g of water to this and heat at 80℃ under nitrogen atmosphere.
After stirring for 30 minutes, the Rh concentration in the upper layer was measured again and it was 1ppm.
had declined to. From this, it is clear that by using the present invention, the elution of Rh into the generated amine layer can be suppressed.

Examples RhCl _{3.3H 2} O: 0.025 g n-propanol: 35 g, 1-decene: 40 g, dimethylamine:
20 g was charged into a 200 ml autoclave with electromagnetic induction stirring, and a reaction was carried out according to the method described in Example 2.

After the reaction, the contents were a pale yellow homogeneous solution with no phase separation. Compositional analysis of this solution showed 97% decene conversion and 86% desired undecyldimethylamine.

To this was added 17 g of water, and after stirring for about 1 hour at 70 to 80° C. under a nitrogen atmosphere, when the mixture was allowed to stand, the contents phase-separated into an almost transparent pale yellow upper layer and a greenish brown lower layer.

Example 4 A reaction was carried out using n-dodecene obtained by dehydrogenation and adsorption separation of n-dodecane.

35 g of polyethylene glycol with an average molecular weight of 400, including 0.053 g of RhCl ₃ 3 H ₂ O, 30 g of the above n-dodecene, and 16 g of dimethylamine were placed in a 200 ml autoclave, and the molar ratio of hydrogen to carbon monoxide was
The reaction was carried out using a mixed gas of 1.7:1.0 at 120 kg/cm ² over 5 hours.

The contents separated into an almost clear upper layer consisting primarily of the product amine and unreacted dodecene, and a lower layer containing most of the catalyst. The dodecene conversion rate was 92% and the tridecyldimethylamine yield was 76%. The Rh concentration in the upper layer was 3 ppm. Water with this:
After adding 12 g and stirring at 70° C. for 30 minutes, the Rh concentration in the upper layer was 1 ppm or less after being left to cool.

After removing water from the lower layer obtained by phase separation in the same manner as described in Example 1, 30 g of n-dodecene and 15 g of dimethylamine were added and the reaction was carried out again, and the catalyst still had sufficient activity. .

Example 5 Methanol containing 0.083 g RhCl ₃ 3H ₂ O: 35
g1-dodecene: 40g, monoethylamine: 6g
Pour 200ml into an autoclave with electromagnetic induction stirring,
Using a mixed gas with a hydrogen:carbon monoxide molar ratio of 1.8:1.0, the reaction was carried out at 110 kg/cm ² over 4 hours.

The contents phase separated into a pale yellow upper layer containing the desired product, diundecylmethylamine, and a lower layer containing most of the catalyst.

Compositional analysis of the upper layer showed a dodecene conversion rate of 97% and a diundecylmethylamine yield of 68%.

The Rh concentration contained in the upper layer was 40 ppm.

Next, 20 g of water was added thereto, and the mixture was stirred at 60 to 80° C. under a nitrogen atmosphere for 30 minutes. After cooling, the upper layer was taken out again, and the Rh concentration was measured to be 6 ppm.

Example 6 RhCl ₃・3H ₂ O: 0.025g, RuCl ₈・3H ₂ O: 0.035
40 g of polyethylene glycol with an average molecular weight of 600 containing g, 40 g of 1-hexene, and 15 g of monoethanolamine were placed in a 200 ml autoclave with electromagnetic induction stirring, and the molar ratio of hydrogen: carbon monoxide was adjusted.
Using a mixed gas of 1.8:1.0, the reaction was carried out at 130 kg/cm ² for 5 hours.

The contents phase-separated into a pale yellow upper layer containing pale yellow diheptyl(2-hydroxyethyl)amine and a reddish brown solvent layer mainly containing polyethylene glycol containing most of the catalyst.

Compositional analysis of the upper layer showed a hexene conversion of 65% and a yield of diheptyl(2-hydroxyethyl)amine, the desired product, of 57%.

Rh concentration in the upper layer is 8ppm, Ru concentration
It was 25ppm. Add 20g of water to this content and approx.
After stirring for 2 hours at 80℃ under nitrogen atmosphere and analyzing after cooling, the Rh concentration in the upper layer was 2ppm, Ru
The concentration had decreased to 10ppm.

Example 7 Diglycerin containing 0.045 g of RhCl _{3.3H 2} O:
40g 1-hexadecene: 34g, dimethylamine:
8 g was charged into a 200 ml autoclave with electromagnetic induction stirring, and the mixture was reacted for 3 hours at 140 kg/cm ² using a mixed gas of hydrogen:carbon monoxide in a molar ratio of 1.9:1.0.

The contents phase-separated into a pale yellow upper layer mainly consisting of heptadecyl dimethylamine and a lower layer mainly consisting of diglycerin containing most of the catalyst.

The composition of the upper layer showed that the hexadecene conversion rate was 94%, the desired heptadecyldimethylamine yield was 81%, and the Rh concentration in the upper layer was 4 ppm.

After 15 g of water was added and treated in the same manner as in Example 6, the Rh concentration in the upper layer was reduced to 1 ppm.

Example 8 40 g of ethanol containing 0.025 g of RhCl ₃ 3H ₂ O,
1-tetradecene: 35g, diethylamine: 20g
Pour 200ml into an autoclave with electromagnetic induction stirring,
Using a mixed gas of hydrogen:carbon monoxide in a molar ratio of 1.7:1.0, the reaction was carried out at a pressure of 110 Kg/cm ² over a period of 4 hours.

After the reaction, the mixture was cooled and the contents were extracted to obtain a pale yellow homogeneous solution without phase separation.

The conversion rate of tetradecene was 97%, and the yield of pentadecyldiethylamine, the target product, was 85%.

Add 15 g of water to this, stir and contact in a nitrogen atmosphere at 50 to 60°C, and let it cool to form an upper layer rich in pentadecyl diethylamine with a slight yellow color.
The phase separated into ethanol and a lower layer mainly composed of water.
At this time, the Rh concentration in the upper layer is 7 ppm, which is the majority of the Rh concentration.
The Rh catalyst was shown to exist in the lower layer.

Claims (1)

[Claims] 1 A long-chain olefin having 6 to 20 carbon atoms, carbon monoxide, hydrogen, and a primary or secondary amine are mixed with carbon as a solvent in the presence of a catalyst whose main component is a compound containing rhodium and/or ruthenium. Monohydric alcohols with numbers 1 to 3, carbon numbers 2 to 3
6 dihydric alcohols, trihydric alcohols having 3 to 6 carbon atoms, and intermolecular dehydration condensates of dihydric or trihydric alcohols having 2 to 3 carbon atoms. , a method for producing tertiary amines by separating the produced tertiary amines from the reaction product, in which water is added to the reaction product to produce the tertiary amine-containing amine. A method for producing tertiary amines, which comprises phase-separating a layer and an aqueous solution layer containing a catalyst.