JP2001172214A - Method for producing diol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a highly pure diol free from an aldehyde. SOLUTION: A primary amine or a phosphite capable of being separated from the diol by distillation is added to a crude reaction product liquid obtained by using a dialdehyde as a starting material and carrying out the reducing reaction of the dialdehyde in the presence of a hydrogenation catalyst and hydrogen, and containing the diol, and the resultant mixture is distilled to provide the objective highly pure diol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing industrially useful diols as raw materials for various polyesters, polyurethanes and polycarbonates. In particular, tricyclodecane dicarbaldehyde and / or pentacyclopentadecane dicarbaldehyde are synthesized by a hydroformylation reaction of dicyclopentadiene and / or tricyclopentadiene, and tricyclodecane dimethanol obtained by hydrogenating the dialdehyde and Pentacyclopentadecane dimethanol is useful as a raw material for the optical material polycarbonate, and it is desired to establish a simple and industrial method for producing high-purity products.

[0002]

2. Description of the Related Art A method for synthesizing a diol by using a dialdehyde as a starting material and performing a reduction reaction in the presence of a hydrogenation catalyst and hydrogen is already known. For example, JP-A-58-14
No. 0030 discloses a method for producing 1,9-nonanediol by reducing 1,9-nonandial in the presence of hydrogen using a Raney nickel, nickel diatomaceous earth or ruthenium / C supported catalyst. In this,
It is described that high-purity 1,9-nonanediol is obtained by removing the catalyst from the crude reaction solution containing the obtained diol by an ordinary operation and then performing fractional distillation. Further, British Patent No. 750144 discloses a method for producing tricyclodecane dimethanol by reducing hydrogen of tricyclodecane dicarbaldehyde obtained by a hydroformylation reaction of dicyclopentadiene in the presence of a nickel catalyst. It is noted. Similarly, as a method for obtaining tricyclodecane dimethanol via dialdehyde generated by hydroformylation of dicyclopentadiene, British Patent No. 1170226 discloses a method of performing hydroformylation and hydrogen reduction using a rhodium catalyst. 63
JP-119429 describes a method by hydrogen reduction using a cobalt compound catalyst. However, these documents do not describe the conditions and the yield when distilling and purifying high-purity tricyclodecane dimethanol from a crude reaction solution containing the target product.

Japanese Patent Application Laid-Open No. 9-124524 proposes a method of extracting and removing an ultraviolet absorbing substance by a liquid / liquid two-layer system as a method for purifying tricyclodecane dimethanol as a raw material of a copolymerized polyester. To obtain tricyclodecane dimethanol, the recovery rate has to be greatly sacrificed. JP-A-11-60525 discloses a method for obtaining a diol with high purity by adding a compound containing a sulfur atom having an unshared electron pair to a crude reaction solution obtained by a hydrogenation reduction reaction, followed by distillation. Although the decomposition of benzene is suppressed to prevent the incorporation of decomposition products having a low boiling point, no method has been proposed for removing impurities having a boiling point close to that of tricyclodecanedimethanol.

[0004]

SUMMARY OF THE INVENTION The present inventors have previously disclosed in Japanese Patent Application No. 10-310818, tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol are useful as a raw material for an optical material polycarbonate. It has been found that the smaller the content of a compound containing an aldehyde group as an impurity, the better the optical properties and color tone of the obtained polymer. Japanese Patent Application Nos. 11-188687 and 11-188688 propose a simple method for producing tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol comprising hydroformylation, solvent extraction, and hydrogenation. However, since the boiling points of the impurity aldehyde group-containing compound and the diols are close to each other, a large loss due to distillation is required to obtain a high-purity product. Therefore, it is desired to establish a method that can easily separate the compound from the impurity aldehyde group-containing compound.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above problems, and as a result, obtained by performing a reduction reaction in the presence of hydrogen and a hydrogenation catalyst using dialdehyde as a starting material. By adding a primary amine or phosphite which can be separated from the diols by distillation to a crude reaction product liquid containing the diols and distilling, a highly pure diol can be easily produced with low loss, high yield and low yield. Heading, the present invention has been completed.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, dialdehydes which are starting materials for the synthesis of diols include those having 4 to 2 carbon atoms.
And a dialdehyde having a linear aliphatic, branched aliphatic, alicyclic or aromatic skeleton. Specifically, butanedial, hexanedial, octanedial,
Nonangial, Decandial, Dodecandial,
Linear aliphatic dialdehydes such as hexadecandial, octadecandial, eicosandials; 2-methyloctanedial, 2-methylnonandial, 2,
Branched aliphatic dialdehydes such as 7-dimethyloctanedial; 1,3-cyclohexanedicarbaldehyde, 1,4-cyclohexanedicarbaldehyde, tricyclodecanedicarbaldehyde, pentacyclopentadecanedicarbaldehyde, bicycloheptanedi Alicyclic dialdehydes such as carbaldehyde; and aromatic dialdehydes such as terephthalaldehyde and isophthalaldehyde. Using the aldehyde as a raw material, corresponding diols are produced.

When these dialdehydes are hydrogenated to obtain the corresponding diols, if the hydrogenation is insufficient, impurities (monoaldehydes, hereinafter abbreviated as monoaldehydes) in which one aldehyde group remains unreacted remain in the diol. Mixed. Monoaldehyde has a small difference in boiling point from diol. It is practically difficult to reduce the amount of the monoaldehyde to zero, which requires an infinitely long hydrogenation reaction time. In the hydrogenation of dialdehydes under ordinary industrially practicable conditions, the incorporation of monoaldehyde in the order of several thousand ppm is inevitable.

As an example of tricyclodecane dimethanol and pentacyclopentadecane dimethanol from tricyclodecane dicarbaldehyde and pentacyclopentadecane dicarbaldehyde which are one of the objects of the present invention, the formulas (I) and ( The monoaldehyde shown as intermediate in II) is formed.

[0009]

Embedded image

[0010]

Embedded image Since these monoaldehydes have a small difference in boiling point from diols, ordinary distillation separation is difficult. In the present invention, a crude reaction solution containing a diol obtained by a hydrogenation reduction reaction is subjected to a method such as general filtration to remove a hydrogenation catalyst contained in the reaction solution, and a low-boiling substance such as a solvent is separated and distilled. Thereafter, the crude diol obtained is purified by distillation to obtain the target diol with high purity.

The primary amine and / or phosphite used in the present invention may be added at a stage before the distillation of the diol substantially in the distillation purification step, in which case a low-boiling substance such as a solvent is separated and distilled. Before or after distillation and purification of the crude diol solution. Before the diol is distilled out of the crude reaction solution to which the primary amine and / or phosphite has been added, the mixture is stirred at a lower temperature for several minutes to several hours to more effectively separate the monoaldehyde. Can be.

The primary amine used in the present invention includes:
Those having a large difference in boiling point from the target diol are preferred. The primary amine added here forms a complex having a higher boiling point than the diol, having a Schiff base bond with the monoaldehyde,
It is separated by distillation as a high boiling component. Unreacted primary amine is separated by distillation using a boiling point difference from the diol. Specifically, it is preferable to use a primary amine having 6 or more carbon atoms, and hexylamine, heptylamine, octylamine, decylamine, dodecylamine, hexadecylamine, octadecylamine, 2-methyloctylamine, 2-methyldodecyl Amines, aliphatic monoamines such as 2,2-dimethyloctylamine, alicyclic monoamines such as cyclohexylamine and aminomethylcyclohexane, aniline, aromatic amines such as naphthylamine;
Aliphatic diamines such as hexanediamine, heptanediamine, octyldiamine, nonanediamine, decyldiamine, alicyclic diamines such as 1,3-bis (aminomethyl) cyclohexane, 4,4′-methylenedianiline;
Examples include aromatic diamines such as diaminonaphthalene, but are not limited thereto.

The phosphite used in the present invention is preferably one having a large difference in boiling point from the target diol. The phosphite added here forms a complex (finally, phosphonic acid) having a higher boiling point than the monoaldehyde and the diol, and is separated by distillation as a high boiling component. Unreacted phosphite is separated by distillation by utilizing the boiling point difference with the diol. As the phosphite, it is preferable to use a phosphite having 6 or more carbon atoms, and alkyl phosphites such as triethyl phosphite, tripropyl phosphite, tributyl phosphite and tricyclohexyl phosphite, triphenyl phosphite, and tris phosphite. (2-t-butylphenyl) phosphite, tris (3-methyl-6
-T-butylphenyl) phosphite, tris (3-methoxy-6-t-butylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite,
Examples include, but are not limited to, aryl phosphites such as di (2-t-butylphenyl) t-butyl phosphite and trinaphthyl phosphite.

The amount of the primary amine and / or phosphite used can be determined according to the amount of the monoaldehyde present in the crude reaction solution of the target diol and the analysis value. The range of use is preferably 0.5 to 10 moles, more preferably 1 to 5 moles per mole of the monoaldehyde. A series of operations in the distillation step does not require special consideration for temperature, pressure, and the like, and is performed according to a known method.

[0015]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Example 1 [Hydroformylation reaction of dicyclopentadiene] Rh (acac) (C) was placed in a 500 mL stainless steel electromagnetically stirred autoclave equipped with a gas inlet tube and a sample outlet tube.
O) ₂ 0.15 g (0.581 mmol), tris- (2,4-di-t-butylphenyl) phosphite 1.88 g (2.91 mmol) and methylcyclohexane 40 g were hydrogen / carbon monoxide = 1/1
(Molar ratio) in a mixed gas atmosphere, and then supply 250 g of dicyclopentadiene while maintaining the internal pressure at 5.0 MPa by supplying a mixed gas of hydrogen / carbon monoxide = 1/1 (molar ratio) into the autoclave. A mixed solution consisting of 10 g of methylcyclohexane as a hydroformylation solvent was continuously fed to the autoclave over 2 hours. During this time,
The temperature inside the autoclave was kept at 100 ° C. After the end of the feed of the above mixed solution containing dicyclopentadiene,
The mixture was further stirred at 100 ° C. for 3 hours to continue the reaction. After the completion of the reaction, a product liquid was obtained from the lower extraction tube of the autoclave. A part of this product solution was sampled and analyzed by gas chromatography. As a result, it was found that the conversion of dicyclopentadiene was 100% and the yield of tricyclodecane dicarbaldehyde was 98.4%. The yield of the monoaldehyde compound in which only one of the double bonds of dicyclopentadiene was hydroformylated was 1.6%.

[Extraction operation] A magnetic stirring bar made of glass, a thermometer for measuring liquid temperature, and a vacuum cock capable of replacing the atmosphere in the apparatus with nitrogen or hydrogen / carbon monoxide are provided so that the extraction layer can be extracted after the extraction operation. An extraction experiment was carried out using a vertical 3L three-necked flask equipped with a cock at the bottom of the apparatus and a jacket type so that the extraction operation temperature could be changed. Ethylene glycol 1000 as extraction solvent in 3L 3-neck flask
g, 0.70 g of N-methyl-diethanolamine as an acetal formation inhibitor
A hydroformylation product liquid to which 950 g was added was introduced, followed by vigorous stirring. The mixture was stirred at 25 ° C. for 30 minutes to reach equilibrium, the stirring was stopped and the mixture was separated into two layers for 30 minutes. A top layer and a bottom extraction solution layer comprising the hydroformylation solvent were obtained. The weight of the hydroformylated solvent layer was 1033.0 g, which contained 28.32 g of tricyclodecanedicarbaldehyde, 2.62 g of monoaldehyde, 0.581 mmol of rhodium as an atom, and 2.91 mmol of phosphorus as an atom. The weight of the ethylene glycol layer was 1332.3 g, which contained 329.3 g of tricyclodecanedicarbaldehyde and 2.29 g of monoaldehyde. Rhodium was 0.003 mmol or less as an atom and phosphorus was 0.01 mmol or less as an atom, which was below the analytical detection limit, and substantially no extraction into the ethylene glycol layer was observed.

In the present experiment, the partition ratio of tricyclodecane dicarbaldehyde and monoaldehyde to the extraction solvent is determined as follows. Partition ratio of component X to extraction solvent = [weight of component X in extraction solvent] / [total weight of component X] As a result, the partition ratio of tricyclodecane dicarbaldehyde was 92.1%, and the distribution of monoaldehyde was 92.1%. The rate was 46.6%. The efficiency of the extraction process can be measured by the distribution coefficient (Kp) of compound [X] and is defined as follows. Kp = [concentration of X in extraction solvent] / [concentration of X in hydroformylation solvent] As a result, the partition coefficient Kp of tricyclodecane dicarbaldehyde was 9.07, and the partition coefficient Kp of monoaldehyde was 0.68.

[Hydrogenation] After adding 50 g of Raney nickel catalyst and 500 g of 2-propanol to a 5 L autoclave equipped with a magnetic stirrer, the inside of the autoclave was replaced three times with a hydrogen pressure of 0.5 MPa. Next, hydrogen was added until the pressure became 1.5 MPa, and the temperature was raised. After the internal temperature of the autoclave reached 130 ° C., hydrogen was further introduced to adjust the internal pressure to 4.0 MPa. Next, to 1332.3 g of an ethylene glycol solution containing tricyclodecane dicarbaldehyde and monoaldehyde obtained by the extraction operation,
The solution mixed with 500 g of propanol was supplied into the autoclave over 2 hours, and the reaction was continued for 2 hours. At this time, the reaction was performed while successively replenishing hydrogen so that the total pressure in the autoclave became 4.0 MPa. After the reaction, the autoclave was cooled and depressurized, and the catalyst component was precipitated from the content and filtered to obtain a reaction solution containing a diol. From this reaction solution, 2-propanol and ethylene glycol as solvents were distilled off using a rotary evaporator to obtain a crude diol product.

[Distillation Purification] In this crude diol product, monoaldehyde is added to tricyclodecane dimethanol.
1500 ppm was present. 100 g of the crude diol product was charged into a simple distillation apparatus, and 1,3-bis (aminomethyl) cyclohexane in an equimolar amount to monoaldehyde was added. The temperature and the degree of vacuum in the lower part of the distillation apparatus were gradually changed to distill off ethylene glycol solvent, a small amount of low-boiling by-products, unreacted 1,3-bis (aminomethyl) cyclohexane, and part of tricyclodecanedimethanol. (The amount of tricyclodecane dimethanol contained in this initial distillation is 4.8% of the total amount of tricyclodecane dimethanol.) Further decompression degree
Distillation was performed at 1.5 torr to obtain tricyclodecanedimethanol as a main fraction at 175 to 178 ° C. The concentration of monoaldehyde in this fraction was 150 ppm. The amount of the high-boiling products remaining in the still was 1.4% based on the obtained tricyclodecane dimethanol.

Comparative Example 1 The distillation purification operation of Example 1 was performed without adding 1,3-bis (aminomethyl) cyclohexane. 100 g of a crude diol product solution in which monoaldehyde is present at 1500 ppm with respect to tricyclodecane dimethanol is charged into a simple distillation apparatus, and the temperature and the degree of decompression at the lower part of the distillation apparatus are gradually changed. A part of the by-product, tricyclodecane dimethanol, was distilled off (the amount of tricyclodecane dimethanol contained in this initial distillation was 36% of the total amount of tricyclodecane dimethanol). Further, distillation was performed at a reduced pressure of 1.5 torr to obtain tricyclodecane dimethanol as a main fraction at 175 to 178 ° C. The concentration of monoaldehyde in this fraction was 1000 ppm. The amount of the high-boiling products remaining in the still was 1.1% based on the obtained tricyclodecane dimethanol. It was difficult to greatly reduce the concentration of monoaldehyde simply by taking a large amount of the first distillation by simple distillation.

Example 2 [Hydroformylation reaction of tricyclopentadiene] A 500 mL content equipped with a gas inlet tube and a sample outlet tube
Rh (acac) in a stainless steel electromagnetic stirring type autoclave
(CO) ₂ 0.0334 g (0.129 mmol), tris- (2,4-di-t
-Butylphenyl) phosphite (2.50 g, 3.86 mmol) and methylcyclohexane (40 g) were combined with hydrogen / carbon monoxide = 1 /
In a mixed gas atmosphere of 1 (molar ratio), 250 g of tricyclopentadiene was charged while a mixed gas of hydrogen / carbon monoxide = 1/1 (molar ratio) was supplied into the autoclave to maintain the internal pressure at 5.0 MPa. , And 60 g of methylcyclohexane as a hydroformylation solvent
It was continuously fed to the autoclave over time. During this time, the temperature inside the autoclave was kept at 100 ° C. After the completion of feeding the above mixed solution containing tricyclopentadiene, the mixture was further stirred at 100 ° C. for 3 hours to continue the reaction. After the completion of the reaction, a product liquid was obtained from the lower extraction tube of the autoclave. A part of this product solution was sampled and analyzed by gas chromatography. As a result, it was found that the conversion of tricyclopentadiene was 100% and the yield of pentacyclopentadecanedicarbaldehyde was 99.0%.
The yield of a monoaldehyde compound in which only one of the double bonds of tricyclopentadiene was hydroformylated (hereinafter simply referred to as "monoaldehyde compound") was 1.0%.

[Extraction operation] A magnetic stirring bar made of glass, a thermometer for measuring liquid temperature, and a vacuum cock capable of replacing the atmosphere in the apparatus with nitrogen or hydrogen / carbon monoxide are provided so that the extraction layer can be extracted after the extraction operation. An extraction experiment was carried out using a vertical 1L three-necked flask of a jacket type equipped with a cock at the bottom of the apparatus and capable of changing the extraction operation temperature. Ethylene glycol 365 as extraction solvent in a 1L 3-neck flask
g and N-methyl-diethanolamine (0.16 g) were charged as an acetal formation inhibitor, a hydroformylation product solution was introduced, and the mixture was vigorously stirred. Mix the mixture at 25 ° C for 30
Stir for minutes to reach equilibrium, stop stirring, and allow the mixture to separate into two layers over 30 minutes. A top layer and a bottom extraction solution layer comprising the hydroformylation solvent were obtained.
The weight of the hydroformylation solvent layer was 109.6 g, which contained 6.53 g of pentacyclopentadecanedicarbaldehyde, 0.55 g of monoaldehyde, 0.129 mmol of rhodium as an atom, and 3.86 mmol of phosphorus as an atom. The weight of the ethylene glycol layer was 488.2 g, and contained 122.4 g of pentacyclopentadecanedicarbaldehyde and 0.60 g of monoaldehyde. Rhodium is 0.003 mmol or less as an atom, and phosphorus is 0.01 mmol or less as an atom, which is below the analytical detection limit,
Substantially no extraction into the ethylene glycol layer was observed.

In the present experiment, the partition ratio of pentacyclopentadecanedicarbaldehyde and monoaldehyde to the extraction solvent is determined as follows. Partition ratio of component X to extraction solvent = [weight of component X in extraction solvent] / [total weight of component X] As a result, the partition ratio of pentacyclopentadecanedicarbaldehyde was 52.2%, and the distribution of monoaldehyde was Rate is 9
4.9%. The efficiency of the extraction process can be measured by the distribution coefficient (Kp) of compound [X] and is defined as follows. Kp = [concentration of X in extraction solvent] / [concentration of X in hydroformylation solvent] As a result, the partition coefficient Kp of pentacyclopentadecanedicarbaldehyde was 4.21, and the partition coefficient Kp of monoaldehyde was 0.25. Was.

[Hydrogenation] After adding 20 g of Raney nickel catalyst and 200 g of 2-propanol to a 2 L autoclave equipped with a magnetic stirrer, the inside of the autoclave was replaced three times with a hydrogen pressure of 0.5 MPa. Next, hydrogen was added until the pressure became 1.5 MPa, and the temperature was raised. After the internal temperature of the autoclave reached 130 ° C., hydrogen was further introduced to adjust the internal pressure to 4.0 MPa. Next, an ethylene glycol solution 488 containing pentacyclopentadecanedicarbaldehyde and monoaldehyde obtained by the extraction operation.
A solution obtained by mixing 200 g of 2-propanol with 2 g was supplied into the autoclave over 2 hours, and the reaction was continued for 2 hours. At this time, the reaction was performed while successively replenishing hydrogen so that the total pressure in the autoclave became 4.0 MPa. After the reaction, the autoclave was cooled and depressurized, and the catalyst component was precipitated from the content and filtered to obtain a reaction solution containing a diol. From this reaction solution, 2-propanol and ethylene glycol as solvents were distilled off using a rotary evaporator to obtain a crude diol product.

[Distillation Purification] The crude diol product liquid contained 1,300 ppm of monoaldehyde based on pentacyclopentadecanedimethanol. 100 g of crude diol production liquid
Was charged into a simple distillation apparatus, and 1,3-bis (aminomethyl) cyclohexane in an equimolar amount to monoaldehyde was added. The temperature and the degree of reduced pressure in the lower part of the distillation apparatus were gradually changed, and an ethylene glycol solvent and a small amount of low-boiling by-products, unreacted 1,3-bisaminomethyl-cyclohexane, and part of pentacyclopentadecanedimethanol were distilled off ( The amount of pentacyclopentadecane dimethanol contained in this initial distillation is 4.5% of the total amount of pentacyclopentadecane dimethanol.) Further, distillation was performed at a reduced pressure of 1.5 torr to obtain pentacyclopentadecanedimethanol as a main fraction at 215 ° C. The concentration of monoaldehyde in this fraction was 130 ppm. The amount of the high-boiling products remaining in the still was 1.3% based on the obtained pentacyclopentadecanedimethanol.

Example 3 The procedure of Example 2 was repeated except that 1,3-bis (aminomethyl) cyclohexane was used instead of tris- (2,4-di-
The reaction was carried out by adding (t-butylphenyl) phosphite. 100 g of crude diol product liquid containing 1300 ppm of monoaldehyde in pentacyclopentadecane dimethanol
Was charged into a simple distillation apparatus, and tris- (2,4-di-t-butylphenyl) phosphite in a molar amount twice as much as that of monoaldehyde was added. The temperature and the degree of decompression in the lower part of the distillation apparatus were gradually changed, and ethylene glycol solvent and a small amount of a low-boiling by-product, pentacyclopentadecanedimethanol, were partially distilled off (pentacyclopentadecanedimethanol contained in the initial distillation was 4.3% of the total amount of pentacyclopentadecane dimethanol). Decompression degree 1.5t
Distillation was performed at orr to obtain pentacyclopentadecane dimethanol as a main fraction at 215 ° C. The concentration of monoaldehyde in this fraction was 120 ppm. The amount of high-boiling products remaining in the distillation still was 1.7% based on the obtained pentacyclopentadecane dimethanol, and unreacted tris-
(2,4-Di-t-butylphenyl) phosphite remained in the still.

[0027]

According to the present invention, aldehyde-free high-purity diols can be produced, which has great industrial significance.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4H006 AA02 AC41 AD11 BA21 BA70 BE20 FC36 FE11 4H039 CA60 CB20

Claims (4)

[Claims] A crude reaction product solution containing a diol obtained by performing a reduction reaction in the presence of a hydrogenation catalyst and hydrogen using a dialdehyde as a starting material, a primary amine which can be separated from the diol by distillation. A method for producing a diol, comprising adding and distilling. 2. The method according to claim 1, wherein the diol is tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol. 3. A crude reaction product solution containing a diol obtained by performing a reduction reaction in the presence of a hydrogenation catalyst and hydrogen using a dialdehyde as a starting material, a phosphite that can be separated from the diol by distillation. A method for producing a diol, comprising adding and distilling. 4. The method according to claim 3, wherein the diol is tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol.