Process for producing dimethylol compound having norbornane skeleton

Abstract

A method for producing a target compound represented by the following formula (1), wherein a mixed solution containing a raw material compound represented by the following formula (2) and a solvent is supplied to a hydrogenation reduction in the presence of a catalyst having hydrogenation ability in a process (A), and water is removed from the reaction system in the process (A), in the formula (1), R represents H, CH3, or C2H5, and in the formula (2), R represents H, CH3, or C2H5, and R1 represents CH3, C2H5, C3H7, or C4H9.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for producing a dimethylol compound having a norbornane skeleton. BACKGROUND

[0002] It is known that dimethylol compounds having a norbornane skeleton exhibit excellent characteristics when used as an adhesive or a resin raw material. As a method for producing dimethylol compounds having a norbornane skeleton, for example, it is described in Patent Literature 1 that dimethylol compounds having a norbornane skeleton are obtained by performing hydrogenation of a corresponding ester compound.

[0003] With respect to a method for producing an aliphatic alcohol by hydrogenating an aliphatic ester compound, many methods have been proposed since the 1930s. For example, as a catalyst for a hydrogenation reaction, a copper-based catalyst containing copper oxide is mainly known, and in the presence of this catalyst, by reacting an ester compound with hydrogen, a hydrogenation reaction can be performed. The activation conditions of these catalysts are determined in consideration of the use form, the use method, the reaction mode, and the like. For example, in the case of adopting a fixed bed reaction mode, in the reduction activation of a shaped catalyst, a gas phase reduction method is adopted, and in Patent Literature 2, in order to avoid local overheating caused by rapid catalyst reduction, it is desired to carefully perform catalyst reduction at a prescribed temperature under the flow of an inert gas having a hydrogen concentration of several percent to several tens of percent.

[0004] On the other hand, in the case of adopting a suspended bed reaction mode, the catalyst form is a powder, and in Patent Literature 3, in the case of activating the catalyst, either of a liquid phase reduction method performed in a gas phase reduction method or a solvent such as a hydrocarbon can be used.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: International Publication No. 2015 / 147242

[0008] Patent Literature 2: Japanese Patent Application Laid-Open No. 61-161146

[0009] Patent Literature 3: Japanese Patent Application Laid-Open No. 1-305042 SUMMARY

[0010] PROBLEMS TO BE SOLVED BY THE INVENTION

[0011] In the case of performing the hydrogenation reaction in a fixed bed reaction system as in Patent Literature 2, the time required for reduction of the catalyst is 4 to 14 days, and the productivity of the aliphatic alcohol is problematic. In addition, in the case of a run-up disorder or a decrease in the activity of the catalyst, there is a concern that the ester compound is mixed in the reaction liquid. In particular, in the case where the target compound is a dimethylol compound having a norbornane skeleton, both the target compound and the intermediate are highly viscous and have a high boiling point, and thus it is difficult to separate them by simple distillation or thin film distillation. On the other hand, in order to separate the above-mentioned target compound (dimethylol compound) by distillation purification with a high number of stages, the yield of the product deteriorates, and thus there is room for improvement from the viewpoint of economy.

[0012] In addition, in the case of performing the hydrogenation reaction in a suspended bed reaction system as in Patent Literature 3, a catalyst using copper oxide and zinc oxide exhibits very high activity even under a low temperature and low pressure reaction condition, but in this technique, there is a concern that a large amount of the intermediate is mixed in the target compound, and the separation thereof is not easy as described above.

[0013] In addition, in Patent Literature 1, it is described that, after the ester compound of the substrate, the solvent, and the catalyst are added, the catalyst activation and the hydrogenation reaction are performed by one pot method, and the reaction temperature is 215°C, the reaction pressure is 10 MPa, the reaction time is 8 hours, and the conditions are mild. However, according to the research by the present inventors, it was confirmed that a significant amount of the intermediate was mixed in the obtained reaction liquid. Furthermore, if the generated target compound is used as a raw material for a polymer in a state where the intermediate is mixed in the above-mentioned amount, the intermediate has a tendency to hinder the reaction to the polymer. Therefore, as in the case of Patent Literature 2, in order to separate the target compound from the intermediate, distillation purification with a high number of stages is required, the yield of the product deteriorates, and thus there is room for improvement from the viewpoint of economy.

[0014] Note that, it is also possible to consider that the reaction time is extended, and the low molecular alcohol produced by the ester decomposition is discarded together with hydrogen gas in order to increase the hydrogen gas concentration in the gas phase, thereby increasing the purity of the target compound, but it is difficult to say that this is the best production method due to the productivity, the loss of hydrogen gas, and the like.

[0015] The present application was completed in view of the above-mentioned problems, and an object thereof is to provide a production method of a dimethylol compound having a norbornane skeleton, which can efficiently perform a hydrogenation reaction and can reduce the amount of mixed intermediate.

[0016] Technical solution to solve the problems

[0017] The present inventors and the like found that, in the production of a dimethylol compound having a norbornane skeleton, by removing water produced as a byproduct from the reaction system at the time of performing the hydrogenation reaction, the above-mentioned problems can be solved, and thus the present application was completed.

[0018] That is, the present application is as described below.

[0019] [1] A production method of a target compound represented by the following formula (1), wherein a mixed solution containing a raw material compound represented by the following formula (2) and a solvent is supplied to a hydrogenation reduction in a process (A) in the presence of a catalyst having a hydrogenation ability,

[0020] In the above process (A), water is removed from the reaction system,

[0021]

[0022] (In the above formula (1), R represents H, CH3, or C2H5.)

[0023]

[0024] (In the above formula (2), R represents H, CH3, or C2H5, and R1 represents CH3, C2H5, C3H7, or C4H9.)

[0025] [2] The production method according to [1], wherein the moisture content of the mixed solution measured after the removal of the water is 4500 ppm or less.

[0026] [3] The production method according to [1] or [2], wherein in the process (A), activation of the catalyst is performed at a first temperature and a first pressure, and after the activation, hydrogenation of the raw material compound is performed at a second temperature and a second pressure.

[0027] [4] The production method according to [3], wherein the water is removed before the hydrogenation.

[0028] [5] The production method according to [3] or [4], wherein the first temperature is 100°C or higher and 170°C or lower, the first pressure is 0.5 MPa or higher and 5 MPa or lower, the second temperature exceeds 170°C and is 250°C or lower, and the second pressure exceeds 5 MPa and is 20 MPa or lower.

[0029] [6] The production method according to any one of [1] to [5], wherein the content of an intermediate represented by the following formula (3) in the target compound is 0.5 mass% or less,

[0030]

[0031] (In the above formula (3), R, R1, and n have the same meanings as those of the formula (2).)

[0032] Effects of the Invention

[0033] According to the present application, it is possible to provide a manufacturing method of a dimethyl alcohol compound having a norbornane skeleton, which can efficiently perform a hydrogenation reaction and can reduce the amount of incorporation of an intermediate. DETAILED DESCRIPTION

[0034] Hereinafter, a mode for carrying out the present application (hereinafter also referred to as "the present embodiment") will be described in detail. The present embodiment below is an example for illustrating the present application, and is not intended to limit the present application to the following content. The present application can be carried out with appropriate modifications within the scope of the gist thereof. Note that, in the present specification, "~" means, unless otherwise specified, a value including both the numerical values at both ends as the upper limit value and the lower limit value.

[0035] <Manufacturing method of dimethyl alcohol compound having norbornane skeleton>

[0036] The manufacturing method of the present embodiment is a method of manufacturing a target compound represented by the following formula (1) (i.e., a dimethyl alcohol compound having a norbornane skeleton represented by the above formula (1), hereinafter also simply referred to as "the target compound"), which has a step (A) of supplying a mixed solution containing a raw material compound represented by the following formula (2) and a solvent to a hydrogenation reduction in the presence of a catalyst having a hydrogenation ability, and removes water from the reaction system in the above step (A).

[0037]

[0038] (In the above formula (1), R represents H, CH3, or C2H5.)

[0039]

[0040] (In the above formula (2), R represents H, CH3, or C2H5, and R1 represents CH3, C2H5, C3H7, or C4H9.)

[0041] The manufacturing method of the present embodiment is configured as described above, and thus, when manufacturing the target compound, it is possible to efficiently perform a hydrogenation reaction and to reduce the amount of incorporation of an intermediate. The target compound can be preferably used as a coating additive, an adhesive, a resin raw material, or the like.

[0042] As a synthetic route for manufacturing the target compound, it is not limited to the following, and for example, a dicyclopentadiene or an olefin having a cyclopentadiene and a functional group can be used as a raw material, and the following synthetic route represented by formula (I) can be employed.

[0043]

[0044] (In the above formula (I), R in formulae (1) to (4) represents H, CH3, or C2H5; and R1in formulae (1) to (3) represents CH3, or C2H5, C3H7, or C4H9.)

[0045] Formula (3) in the above formula (I) represents a synthesis intermediate that can accompany the synthesis of the target compound. Hereinafter, this synthesis intermediate will also be simply referred to as "intermediate" for convenience of explanation.

[0046] [Monoenes having 14 to 19 carbon atoms represented by formula (4)]

[0047] In the present embodiment, the monoenes having 14 to 19 carbon atoms represented by formula (4) below can be produced by carrying out a Diels-Alder reaction of an olefin having a functional group and dicyclopentadiene.

[0048]

[0049] (In formula (4), R represents H, CH3, or C2H5, and R1represents CH3, C2H5, C3H7, or C4H9.)

[0050] As examples of the above olefin having a functional group for Diels-Alder reaction, there are no particular limitations, and examples that can be given include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and the like, of which methyl methacrylate, ethyl methacrylate, methyl acrylate, and ethyl acrylate are preferred.

[0051] The dicyclopentadiene used in the Diels-Alder reaction of the present embodiment is preferably high-purity dicyclopentadiene, preferably dicyclopentadiene having a low content of impurities such as butadiene and isoprene. The purity of the dicyclopentadiene is preferably 90% or more, and more preferably 95% or more. In addition, it is known that dicyclopentadiene depolymerizes under heating conditions to become cyclopentadiene (so-called monocyclopentadiene), and thus cyclopentadiene can also be used instead of dicyclopentadiene. Note that it is believed that the monoenes having 14 to 19 carbon atoms represented by formula (4) above are actually produced via monoenes having 9 to 14 carbon atoms represented by formula (5) below (first-stage Diels-Alder reaction product), and that the monoenes of formula (5) produced are present as new dienophile compounds (Dienophile) in the Diels-Alder reaction (second-stage Diels-Alder reaction) of the cyclopentadiene (Dienophile) present in the reaction system, to produce the monoenes having 14 to 19 carbon atoms represented by formula (4) above.

[0052]

[0053] (In formula (5), R represents H, CH3, or C2H5, and R1represents CH3, C2H5, C3H7, or C4H9.)

[0054] The above-mentioned 2-stage Diels-Alder reaction proceeds efficiently by virtue of the presence of cyclopentadiene in the reaction system, and thus the reaction temperature for the Diels-Alder reaction is preferably 100°C or higher, more preferably 120°C or higher, and further preferably 130°C or higher. On the other hand, in order to suppress the production of high-boiling substances as by-products, the reaction is preferably performed at a temperature of 250°C or lower. In addition, as the reaction solvent, a hydrocarbon, an alcohol, an ester, or the like can be used, and an aliphatic hydrocarbon having 6 or more carbon atoms, cyclohexane, toluene, xylene, ethylbenzene, mesitylene, propanol, butanol, or the like is preferred.

[0055] As the reaction mode for the above-mentioned Diels-Alder reaction, a variety of reaction modes such as a batch mode based on a tank reactor or the like, a semi-batch mode in which a substrate or a substrate solution is supplied to a tank reactor under reaction conditions, a continuous flow mode in which a substrate is circulated in a pipe reactor under reaction conditions, and the like can be employed.

[0056] The reaction product obtained by the above-mentioned Diels-Alder reaction (the mono-olefin having 14 to 19 carbon atoms represented by the above-mentioned formula (4)) can also be used directly as a raw material for the next hydroformylation reaction, but can also be purified by distillation, extraction, crystallization, or the like and then supplied to the next step. Note that the mono-olefin having 14 to 19 carbon atoms represented by the above-mentioned formula (4) is not limited to the substance synthesized as described above, and can also be used in the production method of the present embodiment as long as it can be obtained as a commercial product.

[0057] [Raw material compound represented by formula (2)]

[0058] The raw material compound represented by formula (2) in the above-mentioned formula (I) can be produced, for example, by subjecting the mono-olefin having 14 to 19 carbon atoms represented by formula (4) to a hydroformylation reaction in the presence of a rhodium compound and an organophosphorus compound.

[0059] The rhodium compound used in the above-mentioned hydroformylation reaction is not particularly limited, and a compound that forms a complex with an organophosphorus compound and exhibits hydroformylation activity in the presence of carbon monoxide and hydrogen can be used, for example. Rh(acac)(CO)2 (hereinafter also referred to as "Rh(acac)(CO)2"), Rh203, Rh4(CO) 12 , Rh6(CO) 16Rh(NO3)3, and the like are introduced into the reaction mixture together with the organophosphorus compound, and a rhodium metal hydride carbonyl phosphine complex having catalytic activity is formed in the reaction vessel. Alternatively, a rhodium metal hydride carbonyl phosphine complex can be prepared in advance and introduced into the reactor. In the present embodiment, it is preferable to introduce Rh(acac)(CO)2, which has reacted with the organophosphorus compound in the presence of a solvent, together with excess organophosphorus compound into the reactor as a rhodium-organophosphorus complex having catalytic activity for use in the hydroformylation reaction.

[0060] The amount of the rhodium compound used in the above hydroformylation reaction is preferably 0.1 to 60 micromoles, more preferably 0.1 to 30 micromoles, further preferably 0.2 to 20 micromoles, and still further preferably 0.5 to 10 micromoles, per 1 mole of the monoenes represented by formula (4) having 14 to 19 carbon atoms as the substrate for the hydroformylation reaction. By using the rhodium compound in an amount of less than 60 micromoles per 1 mole of the monoenes having 14 to 19 carbon atoms, the cost of the rhodium catalyst can be reduced even without providing a recycling device for the rhodium complex, and thus the economic burden associated with the recycling device can be reduced.

[0061] In the above hydroformylation reaction, as the organophosphorus compound that forms the rhodium compound and the catalyst for the hydroformylation reaction, a phosphine represented by the general formula P(-R1)(-R2)(-R3) or a phosphite represented by P(-OR1)(-OR2)(-OR3) can be used. As specific examples of R1, R2, and R3 in the above general formula, an aryl group that can be substituted with an alkyl group or an alkoxy group having 1 to 4 carbon atoms, an alicyclic alkyl group that can be substituted with an alkyl group or an alkoxy group having 1 to 4 carbon atoms, and the like can be used, and triphenylphosphine and triphenylphosphite are preferably used. The amount of the organophosphorus compound used is preferably 300 to 10,000 times the amount of rhodium atoms in the rhodium compound, more preferably 500 to 10,000 times, further preferably 700 to 5,000 times, and still further preferably 900 to 2,000 times. When the amount of the organophosphorus compound used is 300 times or more the amount of rhodium atoms, the rhodium metal hydride carbonyl phosphine complex, which is the catalytically active species, is likely to function stably, and as a result, the reaction efficiency tends to be improved. In addition, when the amount of the organophosphorus compound used is 10,000 times or less the amount of rhodium atoms, from the viewpoint of the cost of the organophosphorus compound, the economy tends to be improved.

[0062] The above hydroformylation reaction can also be carried out without using a solvent, but it is preferably carried out by using a reaction-inert solvent. As the solvent, there is no particular limitation as long as it is a solvent that dissolves the mono-olefin having 14 to 19 carbon atoms represented by formula (3), and dicyclopentadiene or cyclopentadiene, and the above rhodium compound, and the above organophosphorus compound. Specifically, there can be mentioned hydrocarbons such as aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, aliphatic esters, alicyclic esters, aromatic esters, aliphatic alcohols, alicyclic alcohols, and aromatic halides. Among them, hydrocarbons are preferred, and among the hydrocarbons, alicyclic hydrocarbons and aromatic hydrocarbons are preferred.

[0063] The temperature at which the above hydroformylation reaction is carried out is preferably from 40°C to 160°C, and more preferably from 80°C to 140°C. In the case where the reaction temperature is 40°C or higher, a sufficient reaction rate can be obtained, and the residual amount of the mono-olefin as a raw material can be suppressed. Further, by making the reaction temperature 160°C or lower, there is a tendency that the generation of by-products from the raw material mono-olefin and the reaction product can be suppressed, and the decrease in the reaction yield can be prevented.

[0064] In the case where the above hydroformylation reaction is carried out, the reaction is carried out under pressurization with carbon monoxide (hereinafter also referred to as "CO") and hydrogen (hereinafter also referred to as "H2"). The CO and H2 gases can be introduced into the reaction system independently, or can be introduced into the reaction system as a pre-prepared mixed gas. The molar ratio (= CO / H2) of the CO and H2 gases introduced into the reaction system is preferably from 0.2 to 5, more preferably from 0.5 to 2, and further preferably from 0.8 to 1.2. In the case where the molar ratio of the CO and H2 gases is within the above range, there is a tendency that the reaction activity of the hydroformylation reaction and the selectivity of the target aldehyde increase. Note that the CO and H2 gases introduced into the reaction system decrease as the reaction proceeds, and therefore if a mixed gas of CO and H2 that is pre-prepared is used, the reaction control is sometimes easy.

[0065] The reaction pressure of the above hydroformylation reaction is preferably from 1 to 12 MPa, more preferably from 1.2 to 8 MPa, and further preferably from 1.5 to 5 MPa. By making the reaction pressure 1 MPa or higher, a sufficient reaction rate can be easily obtained, and there is a tendency that the residual amount of the mono-olefin as a raw material can be suppressed. Further, by making the reaction pressure 12 MPa or lower, an expensive apparatus having excellent pressure resistance is not required, and therefore there is a tendency that it is economically advantageous. In particular, in the case where the reaction is carried out in a batch or semi-batch manner, since the CO and H2 gases are discharged and depressurized after the reaction is completed, the lower the pressure becomes, the less the CO and H2 gases are lost, and therefore there is a tendency that it is economically advantageous.

[0066] The reaction mode in the above-described hydroformylation reaction is preferably a batch reaction or a semi-batch reaction. The semi-batch reaction can be performed by adding a rhodium compound, an organophosphorus compound, and the above-described solvent into a reactor, and performing pressurization based on CO / H2 gas, warming, and the like as the above-described reaction conditions, and then supplying a mono-olefin or a solution thereof as a raw material to the reactor.

[0067] The reaction product obtained in the above-described hydroformylation reaction can also be used directly as a raw material for the next reduction reaction, and can be supplied to the next step after being purified by distillation, extraction, crystallization, or the like. Note that the raw material compound represented by the above-described formula (2) is not limited to the compound synthesized as described above, and can also be used in the production method of the present embodiment if it can be obtained as a commercial product.

[0068] [Process (A)]

[0069] The production method of the present embodiment has a process (A) in which a mixed solution containing a raw material compound represented by the above-described formula (2) and a solvent is supplied to a hydrogenation reduction in the presence of a catalyst having a hydrogenation ability (hereinafter also referred to as "hydrogenation catalyst"). In the present embodiment, in this process (A), by removing water from the reaction system, not only the target compound is obtained from the raw material compound, but also the amount of incorporation of intermediates into the target compound is reduced. This is presumed to be due to the following reasons, but is not intended to be limited to this presumption as the mechanism of action of the present embodiment. That is, it is considered that water is produced as a byproduct in the reaction system of process (A), but the hydrogenation catalyst activated by this water is deactivated. In the present embodiment, it is considered that the activity of the hydrogenation catalyst is easily maintained by removing water, and as a result, the reaction sufficiently proceeds and the amount of incorporation of intermediates is reduced.

[0070] As the hydrogenation catalyst used in process (A), there is no limitation, and for example, a catalyst containing at least one element selected from copper, chromium, iron, zinc, and aluminum can be given. Among them, a copper-based catalyst such as a Cu-Cr catalyst, a Cu-Zn catalyst, a Cu-Zn-Al catalyst, and a Cu-Fe-Al catalyst is preferred, and a Cu-Cr catalyst and a Cu-Zn-Al catalyst are more preferred.

[0071] The above-described hydrogenation catalyst can also be obtained as a commercial product, and for example, E-01X (Cu-Zn-Al catalyst; copper oxide amount 46%, zinc oxide amount 46%, aluminum oxide amount 5%) and N-203S (copper oxide amount 46.1%, chromium oxide amount 43.8%, manganese oxide amount 4.2%) manufactured by Nippon Shokubai Co., Ltd. can be given.

[0072] The amount of the hydrogenation catalyst used is not particularly limited, and is preferably 1 to 50 mass% relative to the starting compound represented by formula (2) as the substrate. When the amount of the hydrogenation catalyst is 1 mass% or more, the reaction proceeds sufficiently, and as a result, there is a tendency for the yield of the target product to increase. In addition, even when the amount of the hydrogenation catalyst is set to more than 50 mass%, there is a tendency for the effect of increasing the reaction rate corresponding to the amount of the catalyst supplied to the reaction to not be obtained, and therefore, from the viewpoint of economy, the amount is preferably set to 50 mass% or less. That is, by setting the amount of the hydrogenation catalyst to the above range, there is a tendency for the hydrogenation reaction to be able to be carried out efficiently. From the above viewpoint, the amount of the hydrogenation catalyst is more preferably 2 to 20 mass%, and further preferably 5 to 10 mass%.

[0073] In the process (A), a solvent is used. As the solvent, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, alcohols, and the like can be mentioned, but are not limited thereto. Among these, alicyclic hydrocarbons, aromatic hydrocarbons, and alcohols are preferably used as the solvent. As preferred specific examples of the above solvent, cyclohexane, toluene, xylene, methanol, ethanol, 1-propanol, cyclohexanol, 2-octanol, and the like can be mentioned.

[0074] In the present embodiment, from the viewpoint of further reducing the amount of the intermediate mixed in, the amount of the moisture of the above mixed solution measured after the removal of the water is preferably 4500 ppm or less, more preferably 4000 ppm or less, and further preferably 3000 ppm or less.

[0075] The above amount of the moisture can be measured based on the method described in the Examples described later.

[0076] Note that, taking the case where a copper-based catalyst is used as the hydrogenation catalyst as an example, the amount of the water by-produced in the reaction system can be predicted from the amount of the copper oxide in the catalyst. That is, the amount of the moisture as a theoretical value can be predicted based on the following formula.

[0077] Amount of moisture = catalyst amount (g) x copper oxide content (mass%) / 100 x 18.015 (molecular weight of water) / 79.545 (molecular weight of copper oxide)

[0078] Based on the predicted value, the amount of the water removed is preferably adjusted in such a manner that the amount of the moisture of the mixed solution becomes the above range.

[0079] In the present embodiment, from the viewpoint of further improving the reaction efficiency, it is preferable that, in the process (A), the activation of the above catalyst is carried out at a first temperature and a first pressure, and after the activation, the hydrogenation of the starting compound is carried out at a second temperature and a second pressure. Note that, as described above, it is considered that the water by-produced deactivates the activated hydrogenation catalyst, and therefore, it is preferable that the water is removed before the hydrogenation is carried out.

[0080] The activation of the hydrogenation catalyst is an operation for reducing the hydrogenation catalyst, and can be performed at a first temperature and a first pressure.

[0081] In the present embodiment, the first temperature is preferably 100°C or higher and 170°C or lower. In the case where the first temperature is 170°C or lower, there is a tendency to suppress the occurrence of side reactions and decomposition reactions. In addition, in the case where the first temperature is 100°C or higher, there is a tendency that the reduction reaction of the catalyst is completed in a moderate time. From the same viewpoint, the first temperature is more preferably 120°C or higher and 170°C or lower.

[0082] In the present embodiment, as the first pressure, it is preferably 0.5 MPa or higher and 5 MPa or lower. In the case where the first pressure is 0.5 MPa or higher, there is a tendency that a sufficient reaction rate can be obtained, and in the case where it is 5 MPa or lower, the loss of H2 gas becomes less at the time of removing water, and thus it is economically advantageous. From the same viewpoint, the first pressure is more preferably 1 MPa or higher and 3 MPa or lower, and further preferably 1.5 MPa or higher and 2 MPa or lower.

[0083] In the present embodiment, as the reaction time in the activation of the hydrogenation catalyst, it is preferably 0.2 hours or longer and 3 hours or shorter. In the case where the first reaction time is 0.2 hours or longer, there is a tendency that the reduction state of the catalyst becomes better, and in the case where it is 3 hours or shorter, there is a tendency that the reduction reaction of the catalyst can be sufficiently performed and the reaction time can be reduced.

[0084] The activation of the hydrogenation catalyst can be performed in the absence of the raw material compound, but in the present embodiment, it is preferably performed in the presence of the raw material compound from the viewpoint of reaction efficiency. In the case where the activation of the hydrogenation catalyst is performed in the presence of the raw material compound, by-product water is generated as a reduction water. As the operation for removing such water, there is no particular limitation, and for example, any one of a method of excluding water existing in the gas phase portion to the outside of the reaction system by performing several purges to the gas phase portion, a method of bubbling H2 gas or an inert gas such as N2 to the outside of the reaction system by providing a nozzle line in the mixed solution in advance. As the judgment of the completion of the treatment, a method of continuing the operation based on 2 to 3 times the amount of assumed water by providing a trap at the end of the exhaust, or a method of measuring the moisture value in the reaction solution can be used.

[0085] The hydrogenation of the raw material compound is an operation for obtaining the target compound, and can be performed at a second temperature and a second pressure.

[0086] In the present embodiment, the second temperature is preferably more than 170°C and 250°C or lower. When the second temperature is 250°C or lower, there is a tendency to suppress the occurrence of side reactions and decomposition reactions, and to obtain the target compound at a high yield. In addition, in the case where the second temperature is more than 170°C, there is a tendency that the reaction is completed in a moderate time, and there is a tendency that it is possible to avoid a decrease in productivity and a decrease in yield of the target. From the same viewpoint, the second temperature is more preferably 190°C or higher and 230°C or lower.

[0087] In the present embodiment, the second pressure is preferably more than 5 MPa and 20 MPa or lower. When the second pressure is 20 MPa or lower, there is a tendency to suppress the occurrence of side reactions and decomposition reactions, and to obtain the target compound at a high yield. In addition, in the case where the second pressure is more than 5 MPa, there is a tendency that the reaction is completed in a moderate time. From the same viewpoint, more preferably more than 5 MPa and 15 MPa or lower, and further preferably more than 5 MPa and 12 MPa or lower.

[0088] Note that, in the hydrogenation in the present embodiment, an inert gas (for example, nitrogen or argon) can also be co-present in the hydrogenation reaction.

[0089] In addition, the above-mentioned pressure refers to a value as a hydrogen partial pressure.

[0090] In the present embodiment, from the viewpoint of the properties obtained when the target compound is further processed, the content of the intermediate represented by the above-mentioned formula (3) in the target compound obtained in the process (A) in the present embodiment is preferably 0.5% by mass or lower. The content of the above-mentioned intermediate can be measured based on the method described in the Examples described later. In addition, the content of the above-mentioned intermediate can be adjusted to the above-mentioned range by the amount of water removed in the process (A).

[0091] The target compound obtained in the process (A) in the present embodiment can be purified, for example, by distillation, extraction, crystallization, or the like.

[0092] Examples

[0093] Hereinafter, the present embodiment will be described in more detail by way of Examples, but the present embodiment is not limited to these Examples.

[0094] <Analysis Method>

[0095] (1) Measurement conditions of gas chromatographic analysis

[0096] Analysis device: Capillary gas chromatograph GC-2010 Plus manufactured by Shimadzu Corporation

[0097] Analysis column 1: InertCap1 (30 m, 0.32 mm I.D., film thickness 0.25 μm) manufactured by GL Science, Inc.

[0098] Column oven temperature 1: 60°C (0.5 minutes) -15°C / minute -280°C (4 minutes)

[0099] Detector 1: FID, temperature 280°C

[0100] Internal standard substance: p-xylene

[0101] Analysis column 2: InertCap WAX (30 m, 0.32 mm I.D., film thickness 0.25 μm) manufactured by GL Science, Inc.

[0102] Column oven temperature 2: 60°C (0.5 minutes) -20°C / minute -250°C (20 minutes)

[0103] Detector 2: FID, temperature 250°C

[0104] (2) GC-MS measurement conditions

[0105] Analysis device: GCMS-QP 2010 Plus manufactured by Shimadzu Corporation

[0106] Ionization voltage: 70 V

[0107] Analysis column: DB-1 (30 m, 0.32 mm I.D., film thickness 1.00 μm) manufactured by Agilent Technologies

[0108] Column oven temperature: 60°C (0.5 minutes) -15°C / minute -280°C (4 minutes)

[0109] (3) Moisture measurement conditions

[0110] Analysis device: coulometric KF moisture meter 899 Coulometer manufactured by Metrohm

[0111] (4) Weight average molecular weight

[0112] Gel permeation chromatography (GPC) was used, tetrahydrofuran was used as the developing solvent, and a standard polystyrene having a known molecular weight (molecular weight distribution = 1) was used to make a standard curve. Based on this standard curve, the retention time from the GPC was calculated. The above GPC measurement was specifically performed under the following conditions.

[0113] Device: HLC-8320 GPC manufactured by Tosoh Corporation

[0114] Column: Guard column: TSKguard column Super MPZ-HZ-M x 1

[0115] Analytical column: TSKgel Super Multipore HZ-M x 3

[0116] Solvent: Tetrahydrofuran

[0117] Injection amount: 10 μL

[0118] Sample concentration: 0.2 w / v% tetrahydrofuran solution

[0119] Solvent flow rate: 0.35 ml / min

[0120] Measurement temperature: 40°C

[0121] Detector: RI

[0122] (5) Glass transition temperature

[0123] Differential scanning calorimeter (DSC) was used. That is, DSC 7000X manufactured by Hitachi High-Technologies Corporation was used as the device, and measurement was performed at a temperature increase and decrease rate of 10°C / min.

[0124] Example 1

[0125] The target compound was synthesized by the route shown in the following Formula (la).

[0126]

[0127] (Obtaining of mono-olefin)

[0128] Into a 500 mL stainless steel reactor, 215 g of methyl acrylate (2.50 mol) and 165 g of dicyclopentadiene (1.25 mol) were charged, and a reaction was performed at 220°C for 2 hours. A reaction liquid containing 152 g of mono-olefin represented by Formula (4a) was obtained, and after purification by distillation, a part of it was supplied to the reaction in the later stage.

[0129] (Obtaining of aldehyde)

[0130] Hydroformylation of the mono-olefin represented by formula (4a) was carried out using a 500 mL stainless steel reactor. To the reactor were added 100 g of the distillatively purified mono-olefin represented by formula (4a), 96 g of 2-octanol (manufactured by Koso Synthetic Industry), 213 mg of triphenylphosphite (manufactured by Wako Pure Chemical Industries) (1500 mol ppm with respect to the mono-olefin), and 355 μg of Rh(acac)(CO)2(manufactured by N.E. Chemcat) (3 mol ppm with respect to the mono-olefin). After three replacements of the atmosphere in the reactor with nitrogen and CO / H2mixed gas, respectively, the system was pressurized with CO / H2mixed gas, and the reaction was carried out at 100°C under 2 MPa for 3 hours.

[0131] After the completion of the reaction, the reaction solution was subjected to gas chromatography and GC-MS analysis, and as a result, 112.6 g of the reaction solution containing the starting compound represented by formula (2a) having a molecular weight of 248 was obtained as the main product (substrate conversion rate 100% (= (input mono-olefin - residual input mono-olefin) / input mono-olefin) x 100%), and the aldehyde yield was 99.5% (= main product / input mono-olefin x 100%).

[0132] Next, the starting compound represented by formula (2a) was subjected to distillative purification, and a part of the purified product was supplied to the reaction in the subsequent step.

[0133] (Reduction of the catalyst and dehydration of the reduction water)

[0134] To a 300 mL stainless steel reactor equipped with a nitrogen bubbling nozzle were added 91.6 g of the distillatively purified starting compound represented by formula (2a), 15.0 g of Cu-Zn-Al catalyst (manufactured by Nippon Kagaku Zoki Mfg. Co., Ltd.: E-01X), and 199.4 g of 2-octanol (manufactured by Koso Synthetic Industry). After three replacements of the atmosphere in the reactor with nitrogen and H2gas, respectively, the system was pressurized with H2gas, and the reduction of the catalyst was carried out at 140°C under 2 MPa for 1 hour. After a trap was installed on the exhaust line, the pressure was reduced to 0 MPa while maintaining the temperature at 140°C, and then a small amount of nitrogen was caused to flow from the nitrogen bubbling nozzle to remove the reduction water in the reaction solution. The amount of the trap was 5.05 g, of which the water content was 1.41 g. In addition, the water concentration in the reaction solution was 2743 ppm.

[0135] (Production of dimethyl alcohol by hydrogenation reaction)

[0136] Next, after three replacements of the atmosphere in the reactor with H2gas, the system was pressurized with H2gas, and the hydrogenation reaction was carried out at 215°C under 9.5 MPa. During the reaction, sampling was carried out every 5 hours.

[0137] The sample solution was diluted with acetone, and the catalyst was filtered with a membrane filter having a pore size of 0.2 μm. The resulting solution was subjected to gas chromatography analysis and GC-MS analysis, and the target compound represented by formula (la) having a molecular weight of 222 and the ester compound (intermediate) represented by formula (3a) having a molecular weight of 250 were quantitatively analyzed as main products. Note that the quantitative analysis was performed using analysis column 2 (InertCap WAX). The intermediate represented by formula (3a) was 0.36% (= intermediate represented by formula (3a) / (all components other than 2-octanol and acetone) x 100) after 15 hours.

[0138] After the reaction, the reaction solution was subjected to gas chromatography analysis using analysis column 1 (InertCap 1), and it was confirmed that the reaction solution contained 79.1 g of the target compound represented by formula (la) (substrate conversion rate 100% (= (input raw material compound - residual raw material compound) / input raw material compound) x 100%)), and the yield of the target compound was 96.5% (= target compound / input raw material compound x 100%).

[0139] Further, the reaction solution was subjected to single distillation purification using a 300 mL three-necked flask equipped with a thermometer, a nozzle for N2 bubbling, and a stirrer (note that the number of distillation stages was one, the distillation temperature was 170 to 180°C, and the vacuum degree was 2 torr). After the purification, the reaction solution was subjected to gas chromatography analysis using analysis column 1 (InertCap 1), and it was confirmed that the main fraction containing the target compound represented by formula (la) was 72.8 g, the dimethyl alcohol purity was 99.2% (= target compound represented by formula (la) / (all components other than acetone) x 100), and the distillation yield was 92.0% (= target compound obtained / input target compound x 100%). In addition, the intermediate represented by formula (3a) was 0.35% (= intermediate represented by formula (3a) / (all components other than 2-octanol and acetone) x 100) using analysis column 2 (InertCap WAX).

[0140] Next, the obtained main fraction 23.53 g (0.106 mol as the target compound), diphenyl carbonate 23.02 g (0.107 mol), and sodium bicarbonate 0.07 mg (0.8 μmol) were put into a 300 mL reactor equipped with a stirrer and a distillation device, and an ester exchange reaction was performed under a nitrogen atmosphere to obtain a polycarbonate resin. The weight average molecular weight (Mw) of the obtained polycarbonate resin was 8,000, and the glass transition temperature (Tg) was 110°C.

[0141] <Comparative Example 1>

[0142] The reaction was carried out by the same procedure as in Example 1 except that the water was not removed from the reaction liquid. The intermediate represented by formula (3a) was 1.00% after 25 hours.

[0143] After the reaction, the reaction liquid was subjected to gas chromatography analysis using an analytical column 1 (InertCap 1) to confirm that the reaction liquid contained 77.5 g of the target compound represented by formula (1a) (substrate conversion rate 100% (= (input raw material compound - residual raw material compound) / input raw material compound) x 100%) and the dimethyl alcohol yield was 94.5% (= target compound / input raw material compound x 100%).

[0144] Further, the reaction liquid was subjected to single distillation purification using a 300 mL three-necked flask equipped with a thermometer, a nozzle for N2 bubbling, and a stirrer (distillation number of stages 1 stage, distillation temperature 170 to 180°C, vacuum degree 2 torr). After the purification, the reaction liquid was subjected to gas chromatography analysis using an analytical column 1 (InertCap 1) to confirm that the main fraction contained 69.0 g of the target compound represented by formula (1a) (purity 98.9% (= target compound represented by formula (1a) / (all components other than acetone) x 100%)) and the distillation yield was 89.0% (= target compound obtained / input target compound x 100%). In addition, the analysis was carried out using an analytical column 2 (InertCap WAX) to confirm that the intermediate represented by formula (3a) was 0.98% (= intermediate represented by formula (3a) / (all components other than 2-octanol and acetone) x 100%).

[0145] Since the dehydration operation was not performed, the intermediate represented by formula (3a) was mixed in the product at more than 0.5% due to the low reduction effect of the intermediate.

[0146] Next, instead of the main fraction obtained in Example 1, the same amount of the main fraction obtained as described above was used, and the ester exchange reaction was carried out in the same manner as in Example 1 to obtain a polycarbonate resin. The weight average molecular weight (Mw) of the obtained polycarbonate resin was 6,800 and the glass transition temperature (Tg) was 105°C.

[0147] <Example 2>

[0148] The hydrogenation catalyst was changed to 9.16 g, and the reaction was carried out by the same procedure as in Example 1 except that. The amount was 3.01 g, of which the water content was 0.85 g. In addition, the water concentration in the reaction liquid was 2585 ppm. In addition, the intermediate represented by formula (3a) after 25 hours in the hydrogenation reaction was 0.44%.

[0149] After the reaction, the reaction solution was subjected to gas chromatography analysis using an analytical column 1 (InertCap 1) to confirm that the reaction solution containing 78.7 g of the target compound represented by formula (la) was obtained (substrate conversion rate 100% (= (input raw material compound - residual raw material compound) / input raw material compound) x 100%), and the dimethyl alcohol yield was 96.0% (= main product / input aldehyde x 100%).

[0150] Further, the reaction solution was subjected to single distillation purification using a 300 mL three-necked flask equipped with a thermometer, a N2 bubbling nozzle, and a stirrer (distillation number of stages 1 stage, distillation temperature 170 to 180°C, vacuum degree 2 torr). After the purification, the reaction solution was subjected to gas chromatography analysis using an analytical column 1 (InertCap 1) to confirm that 71.6 g of a main fraction containing the target compound represented by formula (la) was obtained, the dimethyl alcohol purity was 99.1% (= target compound represented by formula (la) / (all components other than acetone) x 100), and the distillation yield was 91.0% (= target compound obtained / input target compound x 100%). In addition, the analysis using an analytical column 2 (InertCap WAX) was performed to be 0.43% (= intermediate represented by formula (3a) / (all components other than 2-octanol and acetone) x 100).

[0151] Due to the dehydration operation, even if the catalyst is reduced, the intermediate represented by formula (3a) is reduced at a high rate, and the intermediate in the product is less than 0.5%.

[0152] Next, instead of the main fraction obtained in Example 1, the same amount of the main fraction obtained as described above was used, and the ester exchange reaction was performed in the same manner as in Example 1, except that, to obtain a polycarbonate resin. The weight average molecular weight (Mw) of the obtained polycarbonate resin was 7,850, and the glass transition temperature (Tg) was 109°C.

[0153] <Example 3>

[0154] Instead of providing a N2 bubbling nozzle, the gas phase portion was purged 4 times with 0.5 MPa → 0 MPa, and the reaction was performed in the same manner as in Example 2, except that, and the amount was 1.08 g, of which the water content was 0.34 g. In addition, the water concentration in the reaction solution was 4354 ppm. In addition, the ester compound represented by formula (3a) after 25 hours of the hydrogenation reaction was 0.48%.

[0155] After the reaction, the reaction solution was subjected to gas chromatography analysis using an analytical column 1 (InertCap 1), and it was confirmed that the reaction solution containing 78.7 g of the target compound represented by formula (1a) (substrate conversion rate 100% (= (input raw material compound - residual raw material compound) / input raw material compound) x 100%) and the dimethylol yield 95.0% (= target compound / input raw material compound x 100%) were obtained.

[0156] Further, the reaction solution was subjected to single distillation purification using a 300 mL three-necked flask equipped with a thermometer, a nozzle for N2 bubbling, and a stirrer (distillation number of stages 1 stage, distillation temperature 170 to 180°C, vacuum degree 2 torr). After the purification, the reaction solution was subjected to gas chromatography analysis using an analytical column 1 (InertCap 1), and it was confirmed that the main fraction containing the target compound represented by formula (1a) 71.5 g, the dimethylol purity 99.0% (= target compound represented by formula (1a) / (all components other than acetone) x 100), and the distillation yield 90.0% (= target compound obtained / input target compound x 100) were obtained. In addition, the reaction solution was subjected to gas chromatography analysis using an analytical column 2 (InertCap WAX), and it was confirmed that the intermediate represented by formula (3a) was 0.46% (= intermediate represented by formula (3a) / (all components other than 2-octanol and acetone) x 100).

[0157] The dehydration operation was performed so that the water concentration in the reaction solution was 4500 ppm or less, and thus the intermediate represented by formula (3a) was reduced with high efficiency, and the intermediate in the product was less than 0.5%.

[0158] Next, instead of the main fraction obtained in Example 1, the same amount of the main fraction obtained as described above was used, and otherwise, the ester exchange reaction was performed in the same manner as in Example 1, and a polycarbonate resin was obtained. The weight average molecular weight (Mw) of the obtained polycarbonate resin was 7,800, and the glass transition temperature (Tg) was 109°C.

[0159] The results of the reaction conditions and the reaction results of Examples 1 to 3 and Comparative Example 1 are shown in Table 1.

[0160] [Table 1]

[0161]

[0162] This application is based on Japanese Patent Application (Japanese Patent Application No. 2021-067254) filed on April 12, 2021, which is hereby incorporated by reference herein in its entirety.

[0163] Industrial applicability

[0164] According to the production method of the present application, a dimethylol compound having a norbornane skeleton, which is useful as a coating additive, an adhesive, a resin raw material, or the like, can be produced in an industrially advantageous manner.

Claims

1. A production method of a target compound represented by the following formula (1), wherein, ###0001### the production method has a step (A) of supplying a mixed solution containing a raw material compound represented by the following formula (2) and a solvent to a hydrogen reduction in the presence of a catalyst having a hydrogenation ability, ###0002### in the step (A), water is removed from a reaction system, and a water content of the mixed solution measured after the removal of the water is 4500 ppm or less, in the formula (1), R represents H, CH3, or C2H5, in the formula (2), R represents H, CH3, or C2H5, and R1 represents CH3, C2H5, C3H7, or C4H9.

2. The production method according to claim 1, wherein, in the step (A), activation of the catalyst is performed at a first temperature and a first pressure, and hydrogenation of the raw material compound is performed at a second temperature and a second pressure after the activation.

3. The production method according to claim 2, wherein, the water is removed before the hydrogenation.

4. The production method according to claim 2, wherein, the first temperature is 100°C or higher and 170°C or lower, and the first pressure is 0.5 MPa or higher and 5 MPa or lower, the second temperature exceeds 170°C and is 250°C or lower, and the second pressure exceeds 5 MPa and is 20 MPa or lower.

5. The production method according to any one of claims 1 to 4, wherein, a content of an intermediate represented by the following formula (3) in the target compound is 0.5 mass% or less, ###0003### in the formula (3), R, R1, and n have the same meanings as those in the formula (2). ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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