JPS6072844A - Preparation of formylnorbornane containing polar functional group - Google Patents

Abstract

PURPOSE:To obtain the titled compound, by subjecting a norbornene containing a polar functional group to hydroformylation in the presence of a specific catalyst, bringing an aqueous solution of a bisulfite into contact with the prepared reaction mixture so that a formylnorbonane containing a polar functional group is extracted in the form of an addition product in the aqueous solution, separating it from a catalytic phase. CONSTITUTION:A norbornene shown by the formula I (X is polar functional group such as cyano, carbomethoxy, etc.) containing a functional group is subjected to hydroformylation with a mixed gas of H2 and CO in an organic solvent immiscible with water in the presence of a catalyst consisting of a rhodium complex and a triarylphosphine. After the reaction is over, an aqueous solution of a bisulfite is brought into contact with the reaction mixture, formylnorbornane containing a polar functional group is extracted in the aqueous solution in the form of a bisulfite addition product, an organic solvent phase containing the catalyst is separated, to give the desired compound shown by the formula II. The organic solvent phase containing the separated catalyst is recycled to the reaction zone. USE:Various intrmediates useful in polymer fields such as polyester, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the hydroformylation of norbornenes having a polar functional group in the molecule, and more specifically to the hydroformylation of norbornenes containing a polar functional group in the presence of a catalyst consisting of a rhodium complex compound and a triarylphosphine. The present invention relates to a method for separating and recovering a product and a catalyst from a resulting reaction mixture.

There are various intermediates of formylnorbornanes having polar functional groups that are useful in the polymer field.For example, cyanoformylnorbornanes having cyano groups as polar functional groups can be converted into equivalent intermediates by aminohydrogenation reaction in the presence of a hydrogenation catalyst. This diamine can be subjected to condensation polymerization with a polycarboxylic acid to obtain various polyamides.

Additionally, carbomethoxynorbornane, which has a carbomethoxy group as a polar functional group, can be converted to the corresponding diol by hydrogenation in the presence of a hydrogenation catalyst such as copper chromite, while the corresponding diol can be converted by an oxidation reaction. It can also be converted to dicarboxylic acids. Any of these diols or dicarboxylic acids can be used as raw materials for polyester.

Formylnorbornane having such a polar functional group can be obtained by reacting norbornene having a polar functional group with oxo gas in the presence of a catalyst consisting of a rhodium complex compound and triarylphosphine, as shown in the following formula.

Here, X represents a polar functional group, and the formylnorbornane obtained as a product means the compounds shown in the following (I) and (II) alone or in a mixture.

(1) (■) This hydroformylation reaction uses an expensive precious metal catalyst such as a rhodium complex, so it is important for industrialization to efficiently recover the used precious metal catalyst and reduce its loss when recovering the generated aldehydes. This is an important issue.

Several methods have been proposed for recovering the rhodium catalyst from the reaction mixture in the hydroformylation reaction using a rhodium complex compound as a catalyst. JP-A-52-125106, etc.) and a method of separating the product and catalyst by extracting the generated aldehyde into a polar solvent such as water (JP-A-51-29412, etc.) have been proposed, Applied to commercial processes.

Among the above methods, the method by distillation separation is widely adopted in many processes for producing lower aldehydes such as propylene aldehyde and butyraldehyde from lower olefins such as ethylene and propylene.
This is a useful method when the product is a low boiling point compound. However, the polar functional group-containing formylnorbornane, which is the product of the present invention, has a high boiling point, making it difficult to separate the product from the catalyst by distillation. Not only will the recovery rate of the catalyst be reduced, but resinous material will accumulate in the separated catalyst, so a significant amount of the catalyst stream should be removed to prevent resinous material from accumulating in the reaction system by recycling the recovered catalyst. It must be extracted from the system, which reduces the reuse rate of the expensive catalyst.

Furthermore, since the products of the present invention do not have very high solubility in polar solvents, especially water, extractive separation using water is also not effective.

Regarding aldehydes having such a relatively high boiling point and poor solubility in water, the present inventors previously extracted dialdehydes having 8 or more carbon atoms with an aqueous bisulfite solution. proposed a method for separating rhodium complex catalysts as JP-A-58-21638.

However, this method targets dialdehydes; usually, when a monoaldehyde is brought into contact with an aqueous aqueous bisulfite solution to form an alkali bisulfite addition salt, it is soluble in both an aqueous solution and an organic solvent. It was known that the organic phase becomes an adduct and phase separation between the organic phase and the aqueous phase becomes difficult.

As a result of further research on this point, the present inventors have discovered that even monoaldehydes can be extracted with an aqueous bisulfite solution if they have a polar functional group, and have thus arrived at the present invention.

In other words, in the case of dialdehyde, the bisulfite adduct obtained by the following formula has two -CH(OH)SO'' groups in the molecule that have a strong affinity for polar solvents such as water. It has high solubility in polar solvents and can be extracted almost quantitatively, but the cyan group and carbomethoxy group in formylnorbornane containing polar functional groups such as cyanoformylnorbornane and carbomethoxyformylnorbornane are highly soluble in polar solvents. Although it is thought that the 0H(OH)SO7, group does not have a strong affinity, by forming it into a bisulfite adduct, it can be extracted and separated into the aqueous phase in the same way as in the case of dialdehydes. was found to proceed rapidly and quantitatively at room temperature.

That is, in the present invention, norbornene having a polar functional group is hydroformylated with a mixed gas of hydrogen and carbon monoxide in the presence of a rhodium complex compound and a triarylphosphine in an organic solvent that is immiscible with water to formyl having a polar functional group. In the method for producing norbornane, the reaction solution after the completion of the hydroformylation reaction is brought into contact with an aqueous bisulfite solution to extract polar functional group-containing formylnorbornane in the form of a bisulfite adduct into an aqueous solution phase, and the organic compound containing the catalyst is extracted into the aqueous phase. This is a method for producing polar functional group-containing formylnorbornane, which is characterized by separating it from a solvent phase.

The polar functional group-containing norbornene used as a raw material in the present invention can be easily obtained by a Diels-Alder reaction between a polar functional group-containing olefin and cyclopentadiene. For example, cyanonorbornene and carbomethoxynorbornene are easily obtained by reacting acrylonitrile or methyl acrylate with cyclopentadiene, respectively.

A catalyst consisting of a rhodium complex compound and triarylphosphine is used as a hydroformylation reaction catalyst. The triarylphosphine used as a ligand is most preferably triphenylphosphine, but triarylphosphine, tri-p-)lylphosphine, tri-m-)lylphosphine, tris-(p-ethylphenyl)phosphine, or Triarylphosphines having attached substituents which are inert under the hydroformylation reaction conditions, such as lower alkyl or alkoxy groups, such as tris-(p-methoxyphenyl)phosphine, can also be used in the process of the invention.

The hydroformylation reaction solvent used in the present invention can be any organic solvent as long as it is inert under the reaction conditions, dissolves the rhodium catalyst, and is immiscible with the bisulfite aqueous solution, but usually benzene, Aromatic hydrocarbons such as toluene and xylene are particularly preferred.

7- Hydropormylation reaction conditions are 50-2 for temperature.
00°C, preferably 70-150°C, and pressure 30-200 kg/cr&, preferably 30-100 kg/crI.

The composition of the oxo gas used in the reaction is H2/co-10/
Although it can be changed in the range of 1 to 1/10, the range of H210O=2/1 to 1/2 is preferable in consideration of reaction selectivity and the like. There is nothing wrong with including a small amount of gas inert to the reaction, such as nitrogen or methane, in the gas.

The catalyst concentration can be arbitrarily changed depending on the reaction conditions, etc., but considering the reaction rate and selectivity, it is usually 0.5 to 10 mm.
Performed at a concentration of 0.01/l.

The amount of triarylphosphine present in the reaction zone can vary over a wide range from 3 to 300 mol per mol of rhodium, but preferably from 5 to 100 mol per mol of rhodium.

Contact between the reaction solution and the aqueous bisulfite solution after the reaction should be carried out in a state where it is isolated from substances that may have an oxidizing effect such as oxygen, in order to avoid deterioration of the catalyst, aldehyde produced, and bisulfite. This is usually carried out in an atmosphere of an inert gas such as nitrogen. It is also possible to carry out the above operation under an oxo gas atmosphere.

The bisulfite used is bisulfite) IJum,
Potassium bisulfite, cesium bisulfite, etc. are possible, but cesium bisulfite (IJ) is particularly preferred.

The conversion reaction to the bisulfite adduct is carried out at a temperature in the range of 0 to 50°C, but satisfactory results are usually obtained at room temperature. Raising the temperature above this level should be avoided since it increases the deterioration of the rhodium complex and its elution into the aqueous solution layer.

The separated organic solvent containing the rhodium catalyst may be recycled as it is to the hydroformylation reaction zone, but it is preferable to wash it with water before circulating it.

The organic solvent containing the rhodium complex catalyst separated and recovered by the method described above still has sufficient catalytic performance for the hydroformylation reaction, and the organic solvent containing the rhodium complex catalyst that has been separated and recovered by the method described above still has sufficient catalytic performance for the hydroformylation reaction. By adding the containing norbornene and carrying out the hydroformylation reaction under the above-mentioned conditions, the desired polar functional group-containing formylnorbornane can be obtained again.

Next, the present invention will be explained in detail according to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

Example 1 In an electromagnetic induction stirring autoclave with an internal volume of 200 ml,
Rh (CO) (P Ph 3) 30, 16 m
m o ], P Ph 31 , 64 mmol and 5
-cyanonorbornene-2165 mmol to toluene 7
Prepare 0g of dissolved gas and add 7okg/c++ of H2/ao=1/l mixed gas! was supplied until the pressure reached .

The autoclave was heated to 120'C and the reaction was continued for 2 hours, then the heating was stopped and the autoclave was cooled to room temperature.

During the reaction, the pressure inside the autoclave was 70 kg/cn due to the supply of the above-mentioned mixed gas! and 80 kg/c+J.

As a result of analyzing the contents, the conversion rate of the raw material 5-cyanonorbornene-2 was 98.8%, and the yield of the target product 2(3)-formyl-5-cyanonorbornane was 86.8%. It was 9%.

Next, the entire amount of the reaction solution was transferred under a nitrogen atmosphere to a 500 ml flask equipped with a stirrer and a thermometer, and an aqueous solution obtained by dissolving 45 g of sodium bisulfite in 300 ml of water was added thereto. When stirring was started at 20'C, the reaction to form a sodium bisulfite adduct proceeded, and the temperature rose from 20'C to 38°C.

After returning to room temperature, the upper organic solvent phase was separated and analyzed, and it was found that the product, 2(3)-formyl-5-cyanonorbornane, was hardly contained. On the other hand, the lower aqueous solution contains 1.3 ppm of rhodium (
The content of organic phosphorus compounds was only 2 ppm (in terms of phosphorus element).

The results of this analysis indicate that only the generated aldehyde quantitatively transferred into the aqueous solution, with almost no rhodium complex as a catalyst or the theal PPh3 ligand eluting into the aqueous solution.

Example 2 60 g of organic solvent containing the rhodium catalyst recovered in Example 1
160 mmol of 5-cyanonorbornene-11=2 as a raw material was added to the mixture, 8 g of toluene was added as a solvent, and the reaction was carried out again according to the method described in Example 1.

Analysis of the reaction solution revealed that 5-cyanonorbornene-
The conversion rate of 2 was 98.2%, and the desired product 2
(3) The yield of -formyl-5-cyanonorbornane is 8
It was 6.3%. This result shows that the catalyst in the organic solvent separated and recovered according to the present invention still maintains sufficient activity for the hydroformylation reaction.

Example 6 H in an electromagnetic induction stirring autoclave with an internal volume of 200 ml.
Rh(CO)(PPh3)30.12mm01, PPh
A solution of 32.83 mmol and 183 mm+) 1 of carbomethoxynorbornene-2 dissolved in 68 g of toluene was charged, and H,,10O=1,2/1. Ot
D mixed gas was supplied until the pressure reached 60 kg/crd, and the reaction was continued at a temperature of 130°C for 4 hours. Autoclave capacity during reaction is 60kg/cra and 70kg/cra.
It was kept between c++t.

The conversion rate of the raw material 5-carbomethoxynorbornene-12-2 was 99.3%, and the target product 2
The yield of (3)-formyl-5-carbomethoxynorbornane was 76.2%.

The reaction with an aqueous sodium bisulfite solution was carried out according to the method described in Example 1, and the extraction into the aqueous phase was carried out almost quantitatively, with an extraction rate of 98.6%.

Example 4 Rhodium catalyst-containing organic solvent 58 separated and recovered in Example 6
g, the raw material 5-carbomethoxynorbornene-2
170 mmol of and 6 g of toluene were added, and the reaction was carried out again according to the method described in Example B.

As a result of analysis of the reaction solution, the conversion rate of 5-carbomethoxynorbornene-2 was 98.8%, and the desired product 2 (3
The yield of )-formyl-5-carbomethoxynorbornane was 76.3%, indicating that the catalyst recovered by this method still had sufficient hydroformylation ability.

Example 5 HRh (co) (Pph3) 30,643 mm was placed in an electromagnetic induction stirring autoclave with an internal volume of 500 ml.
ol, PPh3], 3 mmol and 620 mm
200g of 5-cyanonorbornene-2 in toluene
was prepared by dissolving it in H,,/CO= 1/l
A mixed gas of 1 was supplied until the pressure reached 60 kg/c+I, and the reaction was continued at a temperature of 120'C for 3 hours. During this time, the pressure inside the autoclave was 60kg/crl and 70k.
gZcrI.

As a result of analysis of the reaction solution, the conversion rate of 5-cyanonorbornene was 98.9%, and the yield of the target product, 2(3)-formyl-5-cyanonorbornane, was 87.9%.

The entire amount of the reaction solution was transferred under a nitrogen atmosphere to a 1500 ml flask equipped with a stirrer and a hygrometer, and an aqueous solution obtained by dissolving 100 g of sodium bisulfite in 800 ml of water was added thereto. Stirring was started to facilitate contact between the lower two layers, and the reaction between the sodium bisulfite and the formed aldehyde began, and the temperature rose from 25°C to 4°C.

When the two layers were cooled to room temperature and analyzed, almost no 2(3)-formyl-5-norbornane was detected, indicating that it was almost quantitatively extracted into the aqueous solution.

The upper layer containing the rhodium complex is separated and collected, and the raw material 5-
Cyanonorbornene-2 600 mmol, toluene 2
When 5 g was added and the reaction was repeated under the same conditions, the reaction results were as follows.

The above results show that the method of separating the rhodium complex catalyst and the product 2(3)-formyl-5-cyanonorbornane according to the present invention is extremely efficient and has almost no negative effect on the catalytic ability of the rhodium complex. It shows that it has not been reached.

Applicant: Mitsubishi Yuka Co., Ltd. Agent: Patent attorney Katsura Atsuta

Claims (4)

[Claims] (1) Norbornene having a polar functional group is hydroformylated with a mixed gas of hydrogen and carbon monoxide in the presence of a rhodium complex compound and a triarylphosphine in an organic solvent that is immiscible with water to produce formylnorbornane having a polar functional group. In the manufacturing method, the reaction solution after the completion of the hydroformylation reaction is brought into contact with an aqueous bisulfite solution, and the polar functional group-containing formylnorbornane is converted into bisulfite eflM.
A method for producing polar functional group-containing formylnorbornane, which comprises extracting the adduct (form D) into an aqueous solution phase and separating it from an organic solvent phase containing a catalyst. (2) The method according to claim 1, wherein the separated organic solvent phase containing the catalyst is recycled into the reaction zone. (3) The method according to claim (1) or (2), wherein the polar functional group is a cyano group or a carbomethoxy group. (4) The method according to any one of claims (1) to (3), wherein the bisulfite is bisulfite.