JP2006062975A - Method for producing 9,10-dihydrophenanthrene - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing 9,10-dihydrophenanthrene industrially advantageous in productivity, cost and the like. <P>SOLUTION: The method for producing 9,10-dihydrophenanthrene comprises a process for hydrogenating phenanthrene in the presence of a hydrogenation catalyst, a process for separating 9,10-dihydrophenanthrene obtained by the hydrogenation and a process for regenerating phenanthrene by dehydrogenating the residue after the separation in the presence of the dehydrogenation catalyst. The regenerated phenanthrene is reused as a raw material of the hydrogenation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for industrially producing 9,10-dihydrophenanthrene. Specifically, the present invention relates to a method for producing 9,10-dihydrophenanthrene, which can effectively use by-products generated during production.

For example, 9,10-dihydrophenanthrene is used as a raw material for obtaining 9,10-dihydrophenanthrene-2,7-dicarboxylic acid ester, which is a raw material for heat-resistant polymers and liquid crystal polymers. It is known as a compound useful for industrial use.
Conventionally, as a method for producing 9,10-dihydrophenanthrene, a method is known in which phenanthrene is hydrogenated in the presence of a hydrogenation catalyst (see, for example, Patent Document 1).
JP-A-1-238545

  However, when phenanthrene is hydrogenated in the presence of a hydrogenation catalyst, for example, in addition to the target 9,10-dihydrophenanthrene, for example, 1,2,3,4-tetrahydrophenanthrene (hereinafter “ THP "), 1,2,3,4,4a, 9,10,10a-octahydrophenanthrene (hereinafter abbreviated as" aOHP "), 1,2,3,4,5,6, Many by-products such as 7,8-octahydrophenanthrene (hereinafter abbreviated as “OHP”) are produced. The amount of by-products other than these 9,10-dihydrophenanthrenes is considerably large, and the separation and purification of these by-products from 9,10-dihydrophenanthrene is extremely difficult. When trying to produce 10-dihydrophenanthrene, there was a problem that the yield was very low and the productivity was very poor. Specifically, conventionally, as a method for isolating 9,10-dihydrophenanthrene from a reaction solution obtained after hydrogenating phenanthrene, generally, the reaction solution is fractionated, and among the obtained fractions, A method of subjecting a fraction containing 9,10-dihydrophenanthrene to crystallization is employed, but in this method, by-products are strictly excluded to obtain high-purity 9,10-dihydrophenanthrene. In order to achieve this, a fraction containing 9,10-dihydrophenanthrene, but also containing by-products, must be discarded without being crystallized. Most of them were to be discarded.

In Patent Document 1, an attempt is made to increase the selectivity of the hydrogenation reaction by using a specific hydrogenation catalyst and to improve the yield of 9,10-dihydrophenanthrene, which is the target product. However, it is practically difficult to completely suppress the formation of by-products, and considering the separation and purification of 9,10-dihydrophenanthrene from the obtained reaction solution, it is industrially It could not be said that the production method was sufficiently satisfactory in terms of points. In addition, since the method disclosed in Patent Document 1 requires a special hydrogenation catalyst, it may be difficult to employ industrially in terms of availability and cost.
Therefore, the problem to be solved by the present invention is to provide a method for producing 9,10-dihydrophenanthrene, which is industrially excellent in productivity and cost.

  The present inventor has intensively studied to solve the above problems. As a result, paying attention to the fact that most of the by-products generated in the phenanthrene hydrogenation reaction are phenanthrene hydrides, the residual produced when 9,10-dihydrophenanthrene is separated and purified from the obtained reaction solution. (For example, when 9,10-dihydrophenanthrene is separated by crystallization after fractionating the reaction solution, all fractions that have not been subjected to crystallization or obtained after crystallization are obtained. The mother liquor was considered to be reused without being discarded. Then, after separating 9,10-dihydrophenanthrene, which is the target product, from the reaction solution, the phenanthrene, which is the raw material, can be easily obtained by dehydrogenating the residue that is normally discarded. The hydride other than the by-product 9,10-dihydrophenanthrene is hydrogenated in any form (that is, any of THP, aOHP, OHP, etc.). And the same phenanthrene was obtained by dehydrogenation, and the present invention was completed.

  That is, the method for producing 9,10-dihydrophenanthrene according to the present invention comprises a step of hydrogenating phenanthrene in the presence of a hydrogenation catalyst, and a reaction solution obtained by the hydrogenation from 9,10-dihydrophenanthrene. Separating the nanthrene, and regenerating phenanthrene by dehydrogenating the separated residue in the presence of a dehydrogenation catalyst, and regenerating the regenerated phenanthrene. Reuse as raw material.

  According to the present invention, it is possible to provide a method for producing 9,10-dihydrophenanthrene, which is industrially excellent in productivity and cost.

Hereinafter, the method for producing 9,10-dihydrophenanthrene according to the present invention will be described in detail. However, the scope of the present invention is not limited to these descriptions, and the scope of the present invention is not limited to the following examples. Changes can be made as appropriate without departing from the above.
The production method of the present invention comprises a step of hydrogenating phenanthrene in the presence of a hydrogenation catalyst (hereinafter also referred to as “hydrogenation step”), and a 9,10-dihydrosilane from a reaction solution obtained by the hydrogenation. A step of separating phenanthrene (hereinafter also referred to as “separation step”), and a step of regenerating phenanthrene by dehydrogenating the residue after separation in the presence of a dehydrogenation catalyst. (Hereinafter also referred to as “regeneration step”), and the regenerated phenanthrene is reused as a raw material for the hydrogenation.

  The hydrogenation step is a step of performing a hydrogenation reaction using phenanthrene as a raw material to synthesize 9,10-dihydrophenanthrene as a target product. In the hydrogenation step, a considerable amount of by-products are usually produced in addition to the target 9,10-dihydrophenanthrene. By-products mainly include hydrides such as THP, aOHP, and OHP. In the hydrogenation step, the reaction yield of 9,10-dihydrophenanthrene, which is the target product, varies depending on the reaction method used and other conditions, but is usually about 43 to 90%. According to the invention, the hydride produced as a by-product is regenerated into phenanthrene and reused as a new raw material, so that the conversion rate of the raw material as a whole manufacturing process is not impaired, and industrially Can maintain good productivity.

It does not specifically limit as a method of the hydrogenation reaction in a hydrogenation process, A well-known method is employable. For example, the phenanthrene and the hydrogenation catalyst may be reacted at a high temperature under pressure of hydrogen in a solvent.
The hydrogenation catalyst that can be used in the hydrogenation step is not particularly limited, and may be appropriately selected from known hydrogenation catalysts in consideration of availability, cost, and the like. In order to efficiently generate dihydrophenanthrene, from the viewpoint of reaction selectivity, for example, a copper chromium catalyst, a Raney nickel catalyst and the like are preferably mentioned, and a copper chromium catalyst is particularly preferable. These catalysts (especially copper chromium catalyst) may contain zinc, manganese, barium and the like as a co-catalyst. Only 1 type may be used for a hydrogenation catalyst and it may use 2 or more types together.

The amount of the hydrogenation catalyst used is not particularly limited. For example, it is preferably 0.05 to 200% by weight, more preferably 1 to 100% by weight, based on the phenanthrene used as a raw material. .
Although it does not specifically limit as a solvent which can be used in a hydrogenation process, For example, ethanol, n-propyl alcohol, methylcyclohexane, etc. are used preferably. Only 1 type may be used for a solvent and it may use 2 or more types together.
Although the usage-amount of the said solvent is not specifically limited, For example, it is preferable that a solvent shall be 100 mL or less with respect to 1 g of phenanthrene used as a raw material.

The reaction temperature and reaction time in the hydrogenation reaction are not particularly limited. For example, the reaction temperature is preferably 100 to 250 ° C., and the reaction time is preferably 10 to 50 hours. Moreover, the hydrogen pressure in the hydrogenation reaction is not particularly limited, but is preferably set to 0.2 to 30 MPa, for example.
The separation step is a step of separating and isolating the target 9,10-dihydrophenanthrene from the reaction solution obtained in the hydrogenation step. The specific means for separating 9,10-dihydrophenanthrene is not particularly limited. For example, the reaction solution is fractionated and crystallized from a part of the fraction (fraction) by 9,10- A preferred means is to obtain dihydrophenanthrene.

  The fractionation is a means for distilling the reaction liquid and separating it by the difference in boiling points. When fractional distillation is performed, the fraction is divided into as many fractions as possible, and 9, Collecting fractions mainly containing 10-dihydrophenanthrene is preferably used for crystallization in order to increase the purity of 9,10-dihydrophenanthrene obtained by strictly eliminating by-products. In order to obtain 9,10-dihydrophenanthrene having a high purity, a fraction mainly containing by-products but fractionally containing 9,10-dihydrophenanthrene is used for crystallization. However, in the present invention, phenanthrene is regenerated from all fractions not subjected to crystallization, including fractions mainly composed of by-products. Therefore, the conversion rate of the raw material as a whole manufacturing process is not impaired, and good productivity can be maintained industrially.

The conditions for performing the fractional distillation are not particularly limited, and known conditions can be employed. For example, it may be distilled under conditions of 0.1 to 50 mmHg (0.013 to 6.7 kPa) and a tower temperature of 100 to 300 ° C. The apparatus that can be used for fractional distillation is not particularly limited, and a known distillation apparatus may be used. For example, a precision distillation column or the like is preferably used.
Conditions for performing the crystallization are not particularly limited, and known conditions can be employed. For example, recrystallization may be performed using n-hexane, methanol or the like as a solvent. In addition, after 9,10-dihydrophenanthrene is precipitated as a crystal by crystallization, it may be filtered, washed, dried, etc. as necessary.

  The regeneration step is a step of regenerating 9,10-dihydrophenanthrene by dehydrogenating the residue after separation obtained in the separation step in the presence of a dehydrogenation catalyst. Here, the residue after the separation is a product derived when 9,10-dihydrophenanthrene is separated from the reaction solution in the separation step, for example, as described above as a preferable means in the separation step. In the case where 9,10-dihydrophenanthrene is separated by crystallization after fractional distillation, the residue after the separation is all fractionated liquids (distilled fractions) not subjected to the crystallization. ) And the mother liquor obtained after the crystallization. Specifically, the residue contains the above-mentioned by-product, that is, a hydride other than the target product of the production method of the present invention. In particular, at least one selected from THP, aOHP, and OHP is included. It is normal to include. In the present invention, phenanthrene is produced (regenerated) by dehydrogenating the residue containing the hydride as a by-product, and the hydride contained in the residue is obtained by the dehydrogenation. Regardless of its type, it is played back to the same phenanthrene. In addition, in the residue, 9,10-dihydrophenanthrene which is the target product may partially remain or phenanthrene which is an unreacted raw material may be contained. The material may be subjected to dehydrogenation.

The method for the dehydrogenation reaction is not particularly limited, and a known method can be employed. For example, the residue and the dehydrogenation catalyst may be reacted at a high temperature. Note that the concentration of the hydride contained in the residue can be adjusted by, for example, concentrating the residue in advance before being subjected to the dehydrogenation reaction.
There is no limitation in particular as a dehydrogenation catalyst which can be used in a reproduction | regeneration process, A well-known dehydrogenation catalyst can be used. For example, palladium carbon, platinum alumina and the like are preferably used. Only 1 type may be used for a dehydrogenation catalyst and it may use 2 or more types together.
The amount of the dehydrogenation catalyst used is not particularly limited. For example, all components contained in the residue subjected to the dehydrogenation reaction are components other than the solvent (residue obtained by removing only the solvent from the residue). On the other hand, it is preferably 0.1 to 50% by weight, more preferably 1 to 20% by weight.

The reaction temperature and reaction time in the dehydrogenation reaction are not particularly limited. For example, the reaction temperature is preferably 150 to 300 ° C., and the reaction time is preferably 10 to 150 hours.
The method for recovering the phenanthrene produced by the dehydrogenation reaction is not particularly limited, and a known method can be employed. For example, the dehydrogenation catalyst may be filtered and then recrystallized.

Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to these examples.
[Example 1]
A 150-L shaking autoclave was charged with 10 kg of phenanthrene, 3 kg of copper-chromium catalyst, and 65 L of n-propyl alcohol, and subjected to a hydrogenation reaction for 15 hours while shaking at 150 ° C. under hydrogen pressure (4 to 6 MPa). The catalyst was removed from the reaction solution. When the reaction solution was analyzed by gas chromatography, the area ratio of each component was as follows.

9,10-dihydrophenanthrene (DHP): 89.0%
aOHP: 0.4%
OHP: 1.3%
THP: 6.0%
Phenanthrene (PHT): 2.8%
Other: 0.5%
Next, a 2190 g portion of the reaction solution obtained by removing the catalyst was placed in a 5 L glass four-necked flask equipped with a thermometer and a precision distillation tower (height 70 cm, inner diameter 2 cm). Was filled with a filler ("Helipak" manufactured by Reciprocating Glass Manufacturing Co., Ltd.) with a height of 30 cm and an inner diameter of 2 cm. Then, under reduced pressure at 15 mmHg (2 kPa), fractional distillation was performed at a tower bottom temperature of 185 to 195 ° C. and a tower top temperature of 167 to 173 ° C., and the distilled fraction was collected in 10 fractions (distilled off). No. 1, No. 2, No. 3,. When the gas chromatography analysis (GC) was performed on each fraction, the area ratio of each component was as shown in Table 1.

Next, in Table 1, No. 3-No. The mixture of fractions 8 was added with 2015.4 mL of n-hexane and crystallized at 1 to 5 ° C. for 10 hours, and the resulting crystals were filtered to obtain 1620.3 g of wet crystals (purity 99.1). %). To this wet crystal, 2015.4 mL of methanol was added and crystallized at 1 to 3 ° C. for 10 hours. The formed crystal was filtered and then dried at 25 ° C. for 50 hours under reduced pressure to obtain a white crystal having a purity of 99.3. % Of purified 9,10-dihydrophenanthrene 1266.9 g (purification yield 63.0%).
On the other hand, no. 3-No. 55.0 g of all fractions other than 8 (fractions No. 1, No. 2, No. 9, and No. 10), and when obtaining the wet crystals and purified 9,10-dihydrophenanthrene A total of 3374 g of the mother liquor obtained at the time of obtaining was mixed, and 337 g was taken from the mixture (the residue after 9,10-dihydrophenanthrene separation) and concentrated to 81.1 g. 10 g from the concentrated mixture was put into a 100 mL glass flask, 800 mg of 7.5 wt% palladium carbon was added, and the mixture was stirred at 200 ° C. for 99 hours to perform a dehydrogenation reaction. To the resulting reaction solution, 40 mL of n-propyl alcohol was added and heated to 80 ° C., and palladium carbon was removed under heating. When this reaction liquid was analyzed by gas chromatography, the area ratio of phenanthrene (PHT) was 98.9%. Subsequently, the reaction liquid from which palladium carbon was removed from the obtained reaction liquid was concentrated to 10.8 g, and recrystallization was performed by adding 50 mL of n-propyl alcohol to the concentrate to thereby obtain 8.8 g of regenerated phenanthrene. Was recovered.

Next, a hydrogenation reaction was performed using the recovered regenerated phenanthrene. That is, 6.25 g of regenerated phenanthrene, 0.313 g of copper chrome catalyst and 100 mL of n-propyl alcohol were charged into a 120 mL stirring type autoclave, and the hydrogenation reaction was performed for 22 hours while stirring at 150 ° C. under hydrogen pressure (4 to 6 MPa). After the reaction, the catalyst was removed from the resulting reaction solution. When the reaction solution was analyzed by gas chromatography, the area ratio of each component was as follows.
9,10-dihydrophenanthrene (DHP): 83.1%
aOHP: 0.3%
OHP: 1.6%
THP: 11.7%
Phenanthrene (PHT): 2.7%
Other: 0.6%
[Example 2]
In carrying out the phenanthrene hydrogenation reaction, two batches of hydrogenation reaction were carried out in the same manner as in Example 1 except that the reaction time was changed to 20 hours and 11 hours. After the reaction, the obtained two batches of reaction liquid were mixed, and the catalyst was removed from the mixed reaction liquid. When this mixed reaction liquid was analyzed by gas chromatography, the area ratio of each component was as follows.

9,10-dihydrophenanthrene (DHP): 88.8%
aOHP: 0.4%
OHP: 1.6%
THP: 5.3%
Phenanthrene (PHT): 3.1%
Other: 0.8%
Next, 7865 g of the mixed reaction solution obtained by removing the catalyst is placed in a 10 L distillation can equipped with a thermometer and a precision distillation column (height 90 cm, inner diameter 5 cm). ("Helipak" manufactured by Mutual Rika Glass Co., Ltd.) was filled at a height of 50 cm and an inner diameter of 5 cm. Then, under reduced pressure at 15 mmHg (2 kPa), fractional distillation was performed at a tower bottom temperature of 184 to 195 ° C. and a tower top temperature of 167 to 170 ° C., and the distilled fraction was collected in three fractions (distilled off). No. 1, No. 2, No. 3 were numbered in order from the beginning). When gas chromatography analysis (GC) was performed on each fraction, the area ratio of each component was as shown in Table 2.

  The remaining part of the mixed reaction solution obtained by removing the catalyst is also divided into four parts, each of which is fractionated in the same manner as described above, and the fraction distilled off each time is divided into three fractions. (No. 1, No. 2, No. 3 were numbered in order from the beginning of evaporation). And No. obtained by each time. 1, no. 2, no. 3 fractions were mixed for each number, and each fraction was subjected to gas chromatography analysis (GC). The area ratio of each component was as shown in Table 3.

Next, No. in Table 2 Then, 1.7 L of n-hexane was added to 7.3 kg of the fraction 2, crystallized at 6-9 ° C. for 10 hours, and the resulting crystals were filtered while being washed with 3.8 L of cooled methanol, then at 25 ° C. It was dried under reduced pressure for 70 hours to obtain 4.4 kg of purified 9,10-dihydrophenanthrene having a purity of 99.6% as white crystals (purification yield 60.3%).
On the other hand, no. 436.5 g of all fractions other than No. 2 (No. 1 and No. 3 fractions) and 6.9 kg of all the mother liquor obtained when obtaining the purified 9,10-dihydrophenanthrene. And the mixture (residue after 9,10-dihydrophenanthrene separation) was concentrated to 3.33 kg. 1.2 kg of the concentrated mixture was taken in a 2 L reactor, 0.12 kg of 7.5 wt% platinum alumina was added, and the mixture was stirred at 240 ° C. for 92 hours to carry out a dehydrogenation reaction. 4.8 L of n-propyl alcohol was added to the obtained reaction liquid and heated to 80 ° C., and platinum alumina was removed under heating. When this reaction liquid was analyzed by gas chromatography, the area ratio of phenanthrene (PHT) was 98.7%. Subsequently, the reaction liquid from which platinum alumina was removed from the obtained reaction liquid was concentrated to 1.27 kg, and 6 L of n-propyl alcohol was added to this concentrate to perform recrystallization, whereby 1.08 kg of regenerated phenanthrene was obtained. Was recovered.

Next, a hydrogenation reaction was performed using the recovered regenerated phenanthrene. Specifically, 100 g of regenerated phenanthrene, 5 g of copper chrome catalyst, and 600 mL of n-propyl alcohol were charged into a 2 L stirring autoclave, and the hydrogenation reaction was performed for 22 hours with stirring at 150 ° C. under hydrogen pressure (4 to 6 MPa). The catalyst was removed from the resulting reaction solution. When the reaction solution was analyzed by gas chromatography, the area ratio of each component was as follows.
9,10-dihydrophenanthrene (DHP): 86.0%
aOHP: 0.3%
OHP: 1.0%
THP: 5.9%
Phenanthrene (PHT): 6.0%
Other: 0.8%

  The method for producing 9,10-dihydrophenanthrene according to the present invention provides, for example, 9,10-dihydrophenanthrene-2,7-dicarboxylic acid ester which is a raw material for heat-resistant polymers and liquid crystal polymers. It can be suitably used for the production of raw materials.

Claims (2)

  A step of hydrogenating phenanthrene in the presence of a hydrogenation catalyst, a step of separating 9,10-dihydrophenanthrene from the reaction solution obtained by the hydrogenation, and dehydrogenating the residue after the separation And regenerating phenanthrene by dehydrogenation in the presence of a hydrogenation catalyst, wherein the regenerated phenanthrene is reused as a raw material for the hydrogenation, and a method for producing 9,10-dihydrophenanthrene.   In the 9,10-dihydrophenanthrene separation step, the reaction solution is fractionated, and 9,10-dihydrophenanthrene is obtained by crystallization from a fraction of the fraction, and the dehydrogenation is performed. The method for producing 9,10-dihydrophenanthrene according to claim 1, wherein the residue to be subjected to crystallization comprises all the fractionated liquids not subjected to crystallization and the mother liquor obtained after the crystallization. .