JP2010018621A - Method for producing diol - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a high purity diol not containing an aldehyde. <P>SOLUTION: A production liquid of raw reaction containing a diol is obtained by performing reduction reaction under the presence of a hydrogenation catalyst and hydrogen, making a dialdehyde as a raw material, is added with a phosphite which can be separated from the diol by distillation, and is distilled to simply produce the high purity diol with small loss and with good yield. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

  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-58-140030 discloses a process for producing 1,9-nonanediol by reducing 1,9-nonanediar in the presence of hydrogen using Raney nickel, nickel diatomaceous earth or ruthenium / C supported catalyst. Has been. Among these, it is described that a high-purity 1,9-nonanediol can be obtained by carrying out fractional distillation after removing the catalyst from the crude reaction solution containing the obtained diol by ordinary operations. British Patent No. 750144 discloses a method for producing tricyclodecane dimethanol by hydrogen reduction of tricyclodecane dicarbaldehyde obtained by hydroformylation of dicyclopentadiene in the presence of a nickel catalyst. It is written. Similarly, as a method for obtaining tricyclodecane dimethanol via dialdehyde produced by hydroformylation of dicyclopentadiene, British Patent No. 1170226 discloses a method for hydroformylation and hydrogen reduction using a rhodium catalyst. Japanese Patent No. 63-119429 describes a method by hydrogen reduction using a cobalt compound catalyst. However, these documents do not describe conditions and yields when high-purity tricyclodecane dimethanol is purified by distillation from a crude reaction solution containing the target product.

  Japanese Patent Application Laid-Open No. 9-124524 proposes a method for extracting and removing ultraviolet absorbing substances by a liquid / liquid two-layer system as a purification method of tricyclodecane dimethanol as a copolyester raw material. In order to obtain candimethanol, the recovery rate must be greatly sacrificed. In JP-A-11-60525, as a method for obtaining a diol with high purity, a diol is obtained by adding a compound containing a sulfur atom having an unshared electron pair to a crude reaction solution obtained by a hydroreduction reaction and distilling it. Although the decomposition of the low boiling point decomposition product is prevented, no proposal has been made on a method for removing impurities having a boiling point close to that of tricyclodecane dimethanol.

  The inventors of the present invention previously described in Japanese Patent Application No. 10-310818, tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol is useful as a raw material of optical material polycarbonate, and is a compound containing an aldehyde group as an impurity. It has been found that the smaller the content, the better the optical properties and color tone of the resulting polymer. In addition, Japanese Patent Application Nos. 11-188687 and 11-188688 propose a simple process for producing tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol comprising hydroformylation, solvent extraction, and hydrogenation. However, since the boiling point of the impurity aldehyde group-containing compound and the diol is close, there are many losses due to distillation in order to obtain a high-purity product. Therefore, establishment of a simple method capable of separation from an impurity aldehyde group-containing compound is desired.

  As a result of diligent investigations to solve the above problems, the present researchers have found that a crude reaction product liquid containing diols obtained by performing a reduction reaction in the presence of a hydrogenation catalyst and hydrogen using dialdehyde as a starting material. Further, by adding a primary amine or phosphite that can be separated from the diol by distillation, the high-purity diol can be easily produced in good yield with little loss, and the present invention has been completed.

  According to the present invention, high-purity diols containing no aldehyde can be produced, and the industrial significance is great.

  Examples of the dialdehyde used as a starting material for the synthesis of diols in the present invention include dialdehydes having a linear aliphatic, branched aliphatic, alicyclic or aromatic skeleton having 4 to 20 carbon atoms. Specifically, linear aliphatic dialdehydes such as butane dial, hexane dial, octane dial, nonane dial, decandial, dodecandial, hexadecandial, octadecandial, eicosandial; 2-methyloctane dial, Branched chain aliphatic dialdehydes such as 2-methylnonane dial and 2,7-dimethyloctane dial; 1,3-cyclohexane dicarbaldehyde, 1,4-cyclohexane dicarbaldehyde, tricyclodecane dicarbaldehyde, penta Examples thereof include alicyclic dialdehydes such as cyclopentadecane dicarbaldehyde and bicycloheptane dicarbaldehyde; and aromatic dialdehydes such as terephthalaldehyde and isophthalaldehyde. Diols corresponding to the aldehydes as raw materials are produced.

  When these dialdehydes are hydrogenated and the corresponding diol is obtained, if the hydrogenation is insufficient, impurities (monoaldehyde, hereinafter abbreviated as one of the aldehyde groups remaining unreacted) are mixed into the diol. Monoaldehyde has a small difference in boiling point from diol. It is practically difficult to make this monoaldehyde zero, and for this purpose, it is necessary to make the hydrogenation reaction time infinitely long. In the hydrogenation of dialdehydes under normal industrially feasible conditions, it is inevitable that monoaldehyde is mixed in the order of several thousand ppm.

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

  Since these monoaldehydes have a small boiling point difference from the diol, ordinary distillation separation is difficult. In the present invention, the crude reaction liquid containing the diol obtained by the hydroreduction reaction is obtained by removing the hydrogenation catalyst contained in the reaction liquid by a general method such as filtration and separating and distilling low-boiling substances such as a solvent. Thereafter, the target diol can be obtained with high purity by purifying the obtained crude diol by distillation.

  The timing of adding the primary amine and / or phosphite used in the present invention is the stage before distilling the diol substantially in the distillation purification process, even before the separation distillation of the low-boiling substances such as solvents. Alternatively, it may be before the subsequent distillation purification of the crude diol solution. Moreover, before the diol distills from the crude reaction liquid to which the primary amine and / or phosphite has been added, the monoaldehyde is more effectively separated by mixing and stirring at a lower temperature for several minutes to several hours. Can do.

  As the primary amine used in the present invention, those having a large difference in boiling point from the target diol are preferable. The primary amine added here forms a complex with a monoaldehyde and a Schiff base bond, which has a higher boiling point than the diol, and is separated by distillation as a high boiling point component. Unreacted primary amine is separated by distillation using a difference in boiling point from diol. Specifically, it is preferable to use a primary amine having 6 or more carbon atoms, such as 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, aromatic amines such as aniline and naphthylamine, hexanediamine, heptanediamine, octyldiamine, nonanediamine, decyldiamine And aliphatic diamines such as 1,3-bis (aminomethyl) cyclohexane, and aromatic diamines such as 4,4′-methylenedianiline and diaminonaphthalene. Not intended to be constant.

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

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

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.
Reference example 1
[Hydroformylation reaction of dicyclopentadiene] Into a 500 mL stainless steel magnetic stirring autoclave equipped with a gas introduction tube and a sample extraction tube, Rh (acac) (CO) ₂ 0.15 g (0.581 mmol), Tris- (2 , 4-di-tert-butylphenyl) phosphite and 40 g of methylcyclohexane were charged in a mixed gas atmosphere of hydrogen / carbon monoxide = 1/1 (molar ratio), and then the autoclave was charged with hydrogen / A mixture of 250 g of dicyclopentadiene and 10 g of methylcyclohexane as a hydroformylation solvent was continuously supplied over 2 hours while supplying a gas mixture of carbon monoxide = 1/1 (molar ratio) and maintaining the internal pressure at 5.0 MPa. Fed to the autoclave. During this time, the temperature in the autoclave was kept at 100 ° C. After completion of the feeding of the above mixture containing dicyclopentadiene, the reaction was continued by stirring at 100 ° C. for an additional 3 hours. After completion of the reaction, the product solution was obtained from the autoclave lower extraction tube. A part of this product solution was sampled and analyzed by gas chromatography. As a result, it was found that the conversion rate of dicyclopentadiene was 100% and the yield of tricyclodecanedicarbaldehyde was 98.4%. The yield of the monoaldehyde compound in which only one double bond of dicyclopentadiene was hydroformylated was 1.6%.

[Extraction operation] A glass magnetic stir bar, a thermometer for measuring liquid temperature, and a vacuum cock capable of replacing the atmosphere in the apparatus with nitrogen or hydrogen / carbon monoxide, and the lower part of the apparatus so that the extraction layer can be extracted after the extraction operation. An extraction experiment was carried out using a vertically long 3 L three-neck flask equipped with a cock and jacket type so that the extraction operation temperature could be changed. Into a 3 L three-necked flask, 1000 g of ethylene glycol as an extraction solvent and 0.70 g of N-methyl-diethanolamine as an acetal formation inhibitor were charged, and a hydroformylation product solution containing 950 g of methylcyclohexane was introduced and stirred vigorously. The mixture was stirred at 25 ° C. for 30 minutes to reach equilibrium, stirring was stopped, and the mixture was allowed to separate into two layers over 30 minutes. A top layer and a bottom extraction solution layer comprising a hydroformylation solvent were obtained. The hydroformylation solvent layer weighed 1033.0 g and 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 ethylene glycol layer weighed 1332.3 g and contained 329.3 g of tricyclodecanedicarbaldehyde and 2.29 g of monoaldehyde. Rhodium was 0.003 mmol or less as atoms, phosphorus was 0.01 mmol or less as atoms and was below the detection limit of detection, and extraction into the ethylene glycol layer was not substantially observed.

In this experiment, the distribution ratio of tricyclodecanedicarbaldehyde and monoaldehyde to the extraction solvent is determined as follows.
Partition ratio of X component to extraction solvent = [weight of X component to extraction solvent] / [total weight of X component]
As a result, the distribution rate of tricyclodecanedicarbaldehyde was 92.1%, and the distribution rate of monoaldehyde was 46.6%. The efficiency of this extraction process can be measured by the partition coefficient (Kp) of compound [X] and is defined as follows.
Kp = [concentration of X in the extraction solvent] / [concentration of X in the hydroformylation solvent]
As a result, the distribution coefficient Kp of tricyclodecanedicarbaldehyde was 9.07, and the distribution 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 to 1.5 MPa, and then the temperature was raised. After the autoclave internal temperature reached 130 ° C., hydrogen was further introduced to adjust the internal pressure to 4.0 MPa. Next, a solution obtained by mixing 500 g of 2-propanol with 1332.3 g of ethylene glycol solution containing tricyclodecanedicarbaldehyde and monoaldehyde obtained by the extraction operation was fed into the autoclave over 2 hours, followed by reaction for 2 hours. Went. At this time, the reaction was carried out while replenishing hydrogen successively so that the total pressure in the autoclave was 4.0 MPa. After the reaction, the autoclave was cooled and released, and the catalyst components were precipitated from the contents and filtered to obtain a reaction solution containing diol. From this reaction solution, 2-propanol and ethylene glycol, which are solvents, were distilled off with a rotary evaporator to obtain a crude diol production solution.

[Distillation Purification] In this crude diol production liquid, 1500 ppm of monoaldehyde was present with respect to tricyclodecane dimethanol. 100 g of the crude diol production solution was charged into a simple distillation apparatus, and an equimolar amount of 1,3-bis (aminomethyl) cyclohexane was added to the monoaldehyde. The temperature at the bottom of the distillation apparatus and the degree of vacuum were gradually changed to distill off a portion of the ethylene glycol solvent and a small amount of low-boiling by-products, unreacted 1,3-bis (aminomethyl) cyclohexane and tricyclodecane dimethanol. (Tricyclodecane dimethanol contained in this first distillation is 4.8% 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 150 ppm. The amount of the high boiling point product remaining in the distillation kettle was 1.4% with respect to the obtained tricyclodecane dimethanol.

Comparative Example 1
The distillation purification operation of Reference Example 1 was performed without adding 1,3-bis (aminomethyl) cyclohexane. 100 g of crude diol product containing 1500 ppm of monoaldehyde with respect to tricyclodecane dimethanol is charged into a simple distillation unit, gradually changing the temperature and degree of vacuum at the bottom of the distillation unit, ethylene glycol solvent and a small amount of low boiling point A part of the by-product, tricyclodecane dimethanol was distilled off (the tricyclodecane dimethanol contained in the first fraction 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 point product remaining in the distillation kettle was 1.1% with respect to the obtained tricyclodecane dimethanol. It was difficult to greatly reduce the concentration of monoaldehyde simply by taking a large amount of the first fraction by simple distillation.

Reference example 2
Stainless steel magnetically stirred autoclave having an inner volume of 500mL provided with a gas inlet tube and a sample withdrawal tube [hydroformylation reaction of tricyclopentadiene], Rh (acac) (CO ) 2 0.0334g (0.129mmol), tris - (2 , 4-di-tert-butylphenyl) phosphite and 40 g of methylcyclohexane were charged in a mixed gas atmosphere of hydrogen / carbon monoxide = 1/1 (molar ratio), and then the autoclave was charged with hydrogen / A mixed gas composed of 250 g of tricyclopentadiene and 60 g of methylcyclohexane as a hydroformylation solvent was supplied over 2 hours while supplying a mixed gas of carbon monoxide = 1/1 (molar ratio) and maintaining the internal pressure at 5.0 MPa. The autoclave was continuously fed. During this time, the temperature in the autoclave was kept at 100 ° C. After the feeding of the above mixture containing tricyclopentadiene, the reaction was continued by stirring at 100 ° C. for an additional 3 hours. After completion of the reaction, the product solution was obtained from the autoclave lower extraction tube. A part of this product solution was sampled and analyzed by gas chromatography. As a result, it was found that the conversion rate of tricyclopentadiene was 100% and the yield of pentacyclopentadecanedicarbaldehyde was 99.0%. The yield of a monoaldehyde form in which only one double bond of tricyclopentadiene was hydroformylated (hereinafter simply referred to as a monoaldehyde form) was 1.0%.

[Extraction operation] A glass magnetic stir bar, a thermometer for measuring liquid temperature, and a vacuum cock capable of replacing the atmosphere in the apparatus with nitrogen or hydrogen / carbon monoxide, and the lower part of the apparatus so that the extraction layer can be extracted after the extraction operation. An extraction experiment was conducted using a vertically long 1 L three-necked flask equipped with a cock and jacket type so that the extraction operation temperature could be changed. Into a 1 L three-necked flask, 365 g of ethylene glycol as an extraction solvent and 0.16 g of N-methyl-diethanolamine as an acetal formation inhibitor were charged, and the hydroformylation product was introduced and stirred vigorously. The mixture was stirred at 25 ° C. for 30 minutes to reach equilibrium, stirring was stopped, and the mixture was allowed to separate into two layers over 30 minutes. A top layer and a bottom extraction solution layer comprising a hydroformylation solvent were obtained. The weight of the hydroformylation solvent layer was 109.6 g, 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 ethylene glycol layer weighed 488.2 g and contained 122.4 g pentacyclopentadecanedicarbaldehyde and 0.60 g monoaldehyde. Rhodium was 0.003 mmol or less as atoms, phosphorus was 0.01 mmol or less as atoms and was below the detection limit of detection, and extraction into the ethylene glycol layer was not substantially observed.

The distribution ratio of pentacyclopentadecanedicarbaldehyde and monoaldehyde to the extraction solvent in this experiment is determined as follows.
Partition ratio of X component to extraction solvent = [weight of X component to extraction solvent] / [total weight of X component]
As a result, the distribution rate of pentacyclopentadecanedicarbaldehyde was 52.2%, and the distribution rate of monoaldehyde was 94.9%. The efficiency of this extraction process can be measured by the partition coefficient (Kp) of compound [X] and is defined as follows.
Kp = [concentration of X in the extraction solvent] / [concentration of X in the hydroformylation solvent]
As a result, the distribution coefficient Kp of pentacyclopentadecanedicarbaldehyde was 4.21, and the distribution coefficient Kp of monoaldehyde was 0.25.

[Hydrogenation] After adding 20 g of Raney nickel catalyst and 200 g of 2-propanol to a 2 L autoclave 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 to 1.5 MPa, and then the temperature was raised. After the autoclave internal temperature reached 130 ° C., hydrogen was further introduced to adjust the internal pressure to 4.0 MPa. Next, a solution obtained by mixing 200 g of 2-propanol with 488.2 g of an ethylene glycol solution containing pentacyclopentadecanedicarbaldehyde and monoaldehyde obtained by the extraction operation was fed into the autoclave over 2 hours, followed by reaction for 2 hours. Went. At this time, the reaction was carried out while replenishing hydrogen successively so that the total pressure in the autoclave was 4.0 MPa. After the reaction, the autoclave was cooled and released, and the catalyst components were precipitated from the contents and filtered to obtain a reaction solution containing diol. From this reaction solution, 2-propanol and ethylene glycol, which are solvents, were distilled off with a rotary evaporator to obtain a crude diol production solution.

[Distillation Purification] In this crude diol production solution, 1300 ppm of monoaldehyde was present with respect to pentacyclopentadecanedimethanol. 100 g of the crude diol production solution was charged into a simple distillation apparatus, and an equimolar amount of 1,3-bis (aminomethyl) cyclohexane was added to the monoaldehyde. The temperature at the bottom of the distillation apparatus and the degree of vacuum were gradually changed to distill off a part of the ethylene glycol solvent and a small amount of low-boiling by-products, unreacted 1,3-bisaminomethyl-cyclohexane and pentacyclopentadecane dimethanol ( 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 point product remaining in the distillation kettle was 1.3% with respect to the obtained pentacyclopentadecanedimethanol.

Example 1
The distillation purification operation of Reference Example 2 was performed by adding tris- (2,4-di-t-butylphenyl) phosphite instead of 1,3-bis (aminomethyl) cyclohexane. 100 g of a crude diol product containing 1300 ppm of monoaldehyde with respect to pentacyclopentadecane dimethanol is charged into a simple distillation apparatus, and tris- (2,4-di-t-butylphenyl) phosphite with twice the molar amount of monoaldehyde is charged. Was added. The temperature at the bottom of the distillation unit and the degree of vacuum were gradually changed to distill off part of the ethylene glycol solvent and a small amount of low-boiling by-product, pentacyclopentadecane dimethanol (the pentacyclopentadecane dimethanol contained in this initial distillation is 4.3% of the total amount of pentacyclopentadecanedimethanol). 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 120 ppm. The amount of the high boiling point product remaining in the distillation kettle was 1.7% with respect to the obtained pentacyclopentadecane dimethanol, and unreacted tris- (2,4-di-t-butylphenyl) phosphite was distilled. Remained in the kettle.

Claims (3)

  Using dialdehyde as a starting material, phosphite that can be separated from the diol by distillation is added to a crude reaction product containing a diol obtained by carrying out a reduction reaction in the presence of a hydrogenation catalyst and hydrogen. A process for producing a diol, characterized in that the diol is tricyclodecane dimethanol and / or pentacyclopentadecane dimethanol, and the phosphite is a phosphite having 6 or more carbon atoms.   The phosphite is triethyl phosphite, tripropyl phosphite, tributyl phosphite, tricyclohexyl phosphite, triphenyl phosphite, tris (2-tert-butylphenyl) phosphite, tris (3-methyl-6-tert-butyl) Phenyl) phosphite, Tris (3-methoxy-6-tert-butylphenyl) phosphite, Tris (2,4-di-tert-butylphenyl) phosphite, Di (2-tert-butylphenyl) tert-butylphos The production method according to claim 1, which is phyto or trinaphthyl phosphite.   The process according to claim 1, wherein the phosphite is tris- (2,4-di-t-butylphenyl) phosphite.