JPH0248541A - Production of terpene alcohol - Google Patents

Abstract

PURPOSE:To obtain the subject compound useful as a synthetic perfumery or its intermediate from a stably available raw material with single step in high yield at an extremely low cost by isomerizing and/or hydrogenating terpinolene-4,8-epoxide in the presence of a copper catalyst. CONSTITUTION:Limonen-4-ol and/or terpinen-4-ol which are monoterpene alcohols which distributed in natural essential oil can be produced at a low cost without using particular apparatuses and water-washing process generating waste-water by isomerizing and/or hydrogenating terpinolene-4,8-epoxide preferably at 70-230 deg.C in the presence of a copper catalyst, preferably Raney copper or copper oxide, especially a copper oxide containing chromium oxide and/or zinc oxide, especially preferably said copper catalyst supported on a carrier, and necessary in the presence of hydrogen gas.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing terpene alcohol, and more particularly, to a method for producing terpene alcohol from terpyrune-4,8-epoxide by isomerization and/or hydrogenation reaction. That is, it relates to a method for producing limonen-4-ol and/or terpinen-4-ol.

[Conventional technology]

Limonen-4-ol (p-mentha-1,8 diene-4
-ol) and terpinen-4-ol (p-menth-1-en-4-ol) are monoterpene alcohols that widely exist in natural essential oils, and are industrially useful compounds as synthetic fragrances or intermediates thereof. It is.

Conventionally, methods for producing the terpene alcohol include: (1) A method for producing terpinen-4-ol from 1,4-cineole using an intramolecular elimination reaction (prior art l, for example, Japanese Patent Laid-Open No. 174738/1983) , JP-A-61-2
60033, JP-A-62-84034), ■ A method of synthesizing limonen-4-ol from terpinolene through a photooxidation reaction, and further hydrogenating it to terpinen-4-ol (Prior Art 2, U.S. Pat. 3,505,41
(Specification No. 2), ■ Limonen-4-ol is synthesized from terpyrine-4.8-epoxide through three steps of amination, oxidation, and hydrolysis (or thermal decomposition), and this is further hydrogenated to produce terpinene-4-ol. Method for manufacturing oar (prior art 3, e.g. U.S. Pat. No. 3,609.197, U.S. Pat. No. 3,676)
．． 504 specification), ■ A method for producing terpinen-4-ol by reducing terpyrune-4,8-epoxide using metallic sodium or lithium aluminum hydride (Prior art 4, Jo
urnal ofScientific and
Industria ■ Re5earch, Vol, 42. Feb
ruary1983, P82-86), ■ A method of isomerizing terpyrune-4,8-epoxide using an alumina catalyst to obtain limonene-4-ol (Prior Art 5, JP-A-62-145034), or A method for isomerizing 4,8-epoxide using p-1-luenesulfonic acid as a catalyst to obtain limonen-4-ol (Prior Art 6, West German Patent No. 2,151)
, No. 492), etc. are known.

(Problems to be Solved by the Invention) However, the method for producing terpinen-4-ol from 1,4-cineole using an intramolecular elimination reaction in Prior Art 1 does not allow for the production of terpinen-4-ol from 1,4-cineole as a raw material. Since pine oil is a byproduct of producing pine oil from pinene, it is unstable in terms of securing raw materials.

In addition, this elimination reaction requires an alkali metal (lithium or sodium) in at least an equimolar amount to the raw material, and these alkali metals cannot be reused, and a large amount of waste water is generated at the same time. It is disadvantageous in terms of raw materials and manufacturing processes, such as the need for a wastewater treatment process.

Further, the method using photo-oxidation reaction of Prior Art 2 requires expensive special equipment and requires a large amount of electric power for the reaction, resulting in high manufacturing costs.

Furthermore, the 3- or 4-step method of Prior Art 3 has a low overall yield and uses a wide variety of non-reusable auxiliary materials.
Since it is used in large quantities and requires many complicated steps, it is not only disadvantageous in the manufacturing process, but also increases the manufacturing cost.

Furthermore, the method of reducing terpyrune-4,8 epoxide using sodium metal or lithium aluminum hydride of Prior Art 4 requires a small amount (equivalent molar amount of sodium metal or lithium aluminum hydride to the raw material), and the manufacturing cost is low. Not only is it expensive, but it also generates a large amount of waste water, which is disadvantageous in terms of the manufacturing process.

Furthermore, in the method of prior art 5 in which terpinen-4,8-epoxide is isomerized using an alumina catalyst, the catalytic activity of the alumina catalyst used is not stable and there are problems with reproducibility. For production, it is necessary to add an additional step of hydrogenation of limonen-4-ol.

Furthermore, the method of isomerizing terpyrune-4.8 epoxide using p-toluenesulfonic acid as a catalyst in Prior Art 6 requires a water washing step to remove the catalyst, and also generates wastewater at the same time, so a separate wastewater treatment step is required. It requires complicated processes such as

Moreover, with the above conventional technology, Terpyrun-4,
There is no known method for producing terpinen-4-ol from 8-epoxide in a single step using a catalyst.

The present invention was made against the background of the above-mentioned problems of the prior art, and uses terpyrune-4,8-epoxide, which is a raw material that does not require special equipment, does not generate waste water, and can be stably supplied. The aim is to obtain the corresponding terpene alcohols, namely limonen-4-ol and/or terpinen-4-ol, in a single step and in high yield and at low cost.

[Means to solve the problem]

The present invention provides a method for producing terpene alcohol by subjecting terpinolene-4,8-epoxide to isomerization and/or hydrogenation reaction (hereinafter sometimes simply referred to as "reaction") using a copper catalyst. be.

Terpyrune-4,8-epoxide used in the present invention can be easily obtained by epoxidizing terpinolene (1,4(8)-p-menthadene) using an organic peracid, hydrogen peroxide, or an organic peroxide. (See, for example, US Pat. No. 3,609,197).

This terpinolene is a monocyclic monoterpene hydrocarbon having two double bonds at the 1- and 4.8-positions, and is produced, for example, by isomerization of d-limonene, which is abundantly obtained from orange oil, and is also a natural product. It can also be obtained from pinene, which is abundant as When this terpinolene is epoxidized, the double bond at the 4.8-position reacts preferentially, so that highly pure terpylene-4,8-epoxide can be easily obtained in high yield.

Next, examples of the copper catalyst used in the present invention include copper metals and copper compounds, especially copper oxides.

Among these, examples of the copper metal include Raney copper.

In addition, examples of copper oxides include copper oxide (Cub), cuprous oxide (CuzO), and hydrated copper oxide (4CuO.H2C).
and mixtures thereof. However, in the case of copper oxides, they have low catalytic activity and poor reactivity when used alone, so in order to increase the catalytic activity to a practical level, these oxides containing carriers, chromium and/or
Alternatively, those containing zinc oxide are preferably used.

That is, the copper oxide is (a) a copper oxide containing a carrier, (b) a copper oxide containing a chromium oxide and/or a zinc oxide, or (c) a copper oxide containing a carrier. chromium oxide and/or
Or those containing zinc oxide.

Here, examples of the carrier include, but are not limited to, diatom, silica, alumina (aluminum oxide), titania (titanium oxide), zirconia (CM-zirconium), and mixtures thereof.

As the copper oxide containing the carrier (a), for example, C
Examples include uO-diatomaceous, CuO-silica, CuO-alumina, and the like.

In addition, (b) the copper oxide containing chromium oxide and/or zinc oxide is Cu0CrtOx (
copper oxide-chromium oxide), CuO-Zn0 (copper oxide-zinc oxide), Cu OCr Z O3-ZnO (copper oxide-
Examples include chromium oxide-zinc oxide).

Furthermore, examples of the copper oxide containing the carrier (c) containing chromium oxide and/or zinc oxide include, for example, Cu OCr 20z-diatomite, CuO
Examples include ZnO-diatomaceous, Cu0-Cr2O2-silica, and the like.

Note that a co-catalyst may be included in the copper catalyst used in the present invention for the purpose of stabilizing and sustaining the catalytic activity.

Examples of this promoter include alkali metals (lithium,
Examples include, but are not limited to, sodium, potassium, etc.) and alkaline earth metals (magnesium, calcium, strontium, barium, etc.).

In this copper catalyst, copper oxide contains chromium oxide and/or
Or when zinc oxide is used in combination, the former/latter (weight ratio) is 9515 to 10/90, preferably 80/'2
It is about 0 to 30/70.

In addition, when the catalyst used in the present invention (w4 oxide, and optionally chromium oxide and/or zinc oxide) is supported on a carrier, the catalyst/support (weight ratio) is as follows:
It is about 80/20 to 30/70.

The copper catalyst used in the present invention can be prepared, for example, by the following method, but is not limited thereto.

That is, while stirring the carrier and pure water well at room temperature,
Add a copper nitrate aqueous solution to this (after mixing, neutralize by gradually adding a sodium carbonate aqueous solution, filter the obtained precipitate, further wash with water, dry at 110°C for several hours, and By firing in an electric furnace at 300 to 500°C for about 3 hours, a copper oxide catalyst having a carrier can be obtained.

Further, the shape of the copper catalyst is not particularly limited, and may be in any shape such as powder, particles, or pellets.

In the reaction of the present invention, a powder is used when the reaction is carried out in a suspended state, and a pellet is used when the reaction is carried out in a fixed bed type, but there are no particular limitations. .

In the present invention, the amount of the catalyst used varies depending on its shape, catalyst composition, and reaction conditions, but is usually 0.05 to 0.05 to
50% by weight, preferably 0, 1 to 30% by weight, more preferably 0.2 to 20% by weight, and 0.05% by weight
If it is less than 50%, the isomerization reaction and/or hydrogenation reaction to terpene alcohol will be too slow, which is undesirable. On the other hand, if it exceeds 50%, not only will the reaction rate not increase proportionally,
This is not preferable because the cost of the catalyst increases.

Further, the catalyst used in the present invention may be used as it is, or may be used after being reduced in advance with hydrogen gas at a temperature of 100 to 300° C. for a certain period of time, for example, 1 to 10 hours.

The reaction in the present invention is carried out under an inert gas stream or in the presence of hydrogen gas.

That is, when the reaction is carried out under an inert gas stream, the reaction can be allowed to proceed by reducing the catalyst in advance.

Further, when the catalyst is used as it is without being reduced, the reaction is difficult to proceed under an inert gas flow, so the reaction can be easily proceeded by carrying out the reaction in the presence of hydrogen gas.

In addition, when the reaction is carried out under an inert gas stream, limonen-4-ol, which is an isomerization reaction product, is mainly produced, so in order to produce terpinen-4-ol, it is necessary to , limonene-4 produced by introducing hydrogen gas
Terpinen-4-ol can be easily obtained by further hydrogenating -ol. Here, nitrogen gas is usually used as the inert gas from the viewpoint of ease of extraction and cost.

Furthermore, when the reaction is carried out in the presence of hydrogen gas, not only an isomerization reaction but also a hydrogenation reaction occurs depending on the pressure conditions of the hydrogen gas.

The pressure of this hydrogen gas varies depending on the reaction temperature, but is usually 0.1 to 0.1 look/cd, preferably 0.2 to 5
If it is less than 0 kg/cd, the isomerization reaction and/or hydrogenation reaction is too slow, while if it is more than 100 kg/cj, terpinolene-4,8-
There are many side reactions such as epoxide dehydration and decomposition reactions, which reduces the yield of the target terpene alcohol.

Furthermore, as mentioned above, an advantage of the present invention is that either limonen-4-ol or terpinen-4-ol can be selectively obtained in a single step using the catalyst used in the present invention. This becomes possible by changing the pressure conditions of hydrogen gas.

That is, under low hydrogen pressure, terpinolene-4.8-
Epoxide isomerization mainly occurs, with limonene-4-
Mainly produced by oars.

On the other hand, under high hydrogen pressure, terpyrune-48-epoxide is directly hydrogenated or isomerized to limonen-4-ol, and then limonen-4-ol is further hydrogenated to form terpinen-4-ol. Mainly generated.

The hydrogen pressure of the isomerization reaction that mainly produces limonen-4-ol varies depending on the type of catalyst, the shape of the catalyst, the reaction temperature, the type of reaction solvent described later, etc., but is usually 0.
1-10 kg/cffl, preferably 0. 2~7k
g/eel, and if it is less than 1 kg/c+J, the isomerization reaction rate is slow, while if it exceeds 10 kg/cI, the double bond at position 8.9 of the limonen-4-ol produced will be hydrogenated. As a result, the production of terpinen-4-ol becomes significant.

In addition, the hydrogen pressure in the hydrogenation reaction that mainly produces terpinen-4-ol is usually over 10 kg/Ci.
kg/cal or less, preferably 15 to 50 kgZd.

In addition, in order to produce only limonen-4-ol, it is also possible to adopt a method in which the catalyst is reduced in advance as described above and then the reaction is carried out under an inert gas stream.

In addition, as a method for obtaining only terpinen-4-ol, terpinolene-4,8-epoxide is first reacted under low hydrogen pressure to produce limonen-4-ol, and then hydrogenated at high hydrogen pressure to further hydrogenate. Terpinene-4-
Or may be generated.

Thus, according to the method of the present invention, any desired terpene alcohol can be obtained in a single step in the same reaction.

When carrying out the isomerization and/or hydrogenation reaction of the present invention, a reaction solvent such as a hydrocarbon can be used, but it is not necessary to use this reaction solvent.

Examples of the reaction solvent include aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as hexane, heptane, and octane; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and cyclooctane; methanol, ethanol, n-propanol, isopropanol, n-butanol, 5ec-butanol, L
- Saturated lower alcohols such as butanol and isobutanol; and glycols such as ethylene glycol, propylene glycol and butanediol.

When a reaction solvent is used in the present invention, the amount of reaction solvent used is usually O to 0 to terpyrune-4,8-epoxide.
The ratio is 30 times by weight, preferably 0 to 10 times by weight, and if it exceeds 30 times by weight, the reaction rate will be slow and the amount of by-products will increase, resulting in a yield of the target terpene alcohol (ii!
This is not preferable because not only the selectivity (selectivity) is lowered but also the cost of the solvent is increased.

The isomerization and/or hydrogenation reactions in the present invention are carried out in a liquid phase. The reaction temperature at that time varies depending on the composition and amount of the catalyst used, but is usually 70-230°C.
°C, preferably 90 to 190 °C. Below 70 °C, the reaction rate is too slow; while above 230 °C, side reactions such as dehydration and decomposition increase, resulting in a decrease in the yield (selectivity) of the target terpene alcohol. ) is undesirable because it decreases.

In addition, the reaction time of isomerization and/or hydrogenation in the present invention is not particularly limited, and varies depending on the composition and amount of the catalyst used, the reaction temperature, and the reaction format.
From the viewpoint of operability and economy, the time is usually 0.5 to 50 hours, preferably 1 to 30 hours.

When carrying out the isomerization and/or hydrogenation reaction of the present invention, the reaction format may be either Hutch reaction or continuous reaction, and the reactor used may be a stirred tank, a packed column, or a combination of a stirred tank and a packed column. It can be in any format.

For example, when using a powdered catalyst, a stirred tank format is preferably used, in which terpinolene-4°8-epoxide and the catalyst are charged, as well as a solvent if necessary, and the mixture is heated at a predetermined temperature and under a predetermined hydrogen pressure. The reaction is carried out by stirring.

Furthermore, when a particulate or pelleted catalyst is used, a packed column format or a combination of a stirring tank and a packed column is preferably used. In the case of this packed column type, for example, terpinolene-4.8-
By passing a mixture of epoxide and optionally a solvent together with hydrogen gas, or if a stirred tank and a packed tower are used together, the packed tower is filled with a predetermined amount of catalyst and the terpinole is pumped from the stirred tank. - 4,8-Epoxide is introduced into a packed column, passed through the packed column under a predetermined hydrogen pressure and at a predetermined temperature, and the reactant is returned to a stirring tank, thereby continuously circulating the packed column. The reaction can be carried out by

At this time, the catalyst may be reduced in advance as described above and the reaction may be carried out under an inert gas stream. After the reaction is completed, if the reaction is carried out in suspension, the reaction product is separated into solid and liquid by means such as filtration or precipitation, or if the reaction is carried out in a fixed bed, the reaction product is It is recovered as is without solid-liquid separation.

The reaction product obtained by the reaction of the present invention contains impurities such as hydrocarbons and oxygen-containing compounds such as alcohol in addition to the target terpene alcohol, so it is usually purified by cleaning. , high purity terpene alcohol can be obtained. however,
When using a reaction solvent, it is necessary to collect the reaction solvent in advance prior to rectification. Moreover, the unreacted terpinolene-4,8-epoxide recovered by the rectification at this time can be reused as a reaction raw material.

[Effect]

According to the present invention, the epoxide present between the 4-8 positions of terpinolene-4,8-epoxide undergoes an isomerization and/or hydrogenation reaction using a copper catalyst, and an OH bond is formed at the 4-position, and an OH bond is formed at the 8-9 position. Either isomerization occurs to selectively form a double bond at the 4-position, hydrogenation occurs to selectively form an OH bond at the 4-position, or isomerization occurs at the 4-position, followed by isomerization at the 8-position. The double bond at position ˜9 is selectively hydrogenated, so that the terpene alcohols, namely limonen-4-ol and/or terpinen-4-ol, are obtained in high yield and in a single step.

Thus, during this reaction, terpene alcohol can be obtained at low cost without producing waste water or requiring expensive equipment.

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples. In the examples, unless otherwise specified, parts and percentages are based on weight.

Example 1 In a stainless steel autoclave equipped with a stirrer, a thermometer, and a hydrogen gas inlet tube, 60 parts of terpyrune-4,8-epoxide (purity 98.8% by gas chromatography) and powdered copper oxide-diatomaceous earth catalyst 5C were placed. −1(Cu
b/ (diatomaceous earth + barium) (weight ratio) = 2/1.
[manufactured by Sakai Kagaku Kogyo ■] and 60 parts of ethanol were charged, and after replacing the inside of the system with nitrogen gas, hydrogen gas was introduced to set the pressure to 5 kg/cnl.

Next, the mixture was heated while being stirred, and the reaction was carried out at 140° C. for 9 hours while being stirred.

As a result of sampling the reaction product liquid and analyzing it by capillary gas chromatography, it was found that Terpyrun-4.8
- Epoxide conversion was 99.3%, product selectivity was 72.6% for limonene-4-ol, terpinene-4-ol
4-all is 9. It was 1%. Further, as by-products, 9.4% of hydrocarbons and 8.9% of oxygen-containing compounds were produced. Furthermore, the reaction temperature was 140°C, and the hydrogen pressure was 30°C.
The reaction was carried out for 9 hours at kg/cnl. During this time, hydrogen gas was absorbed by the reaction, so hydrogen gas was added to keep the pressure constant.

As a result of the same analysis, the reaction product liquid was found to be terpinolene-4.
, 8-epoxide was 100%, and the product selectivity was 79.9% for terpinen-4-ol, 13.8% for by-product hydrocarbons, and 6.8% for oxygenated compounds. 3
%, and the presence of limonen-4-ol was not observed.

The reaction product liquid thus obtained was separated and removed by filtration to remove the catalyst, further desolventized, and then rectified under reduced pressure to obtain a fraction with a boiling point of 75 to 78°C/4**Hg.
7 parts (yield=76.1%) were obtained. As a result of analyzing this fraction by capillary gas chromatography,
It contained 96.3□% of terpinen-4ol.

Examples 2 to 5 Reactions were carried out in the same manner as in Example 1, except that the amounts charged and reaction conditions were changed as shown in Table 1. Table 1 shows the conversion rate of terpyrune=4.8-epoxide and the selectivity of the product in the reaction product solution at that time.

Table 1 Note) In Example 3, the reaction was carried out under the reaction conditions (2), and then the reaction was roughly carried out under the conditions (2).

I did it. As a result, the conversion rate of terpyrune-4,8-epoxide was 91.5%, and the selectivity of the product was 91.5%.
68.2% 4-ol, 6% terpinen-4-ol
．． 0%, by-product hydrocarbons were 11.4%, and oxygen-containing compounds were 14.4%.

Examples 8 to 11 In Example 1, the reaction was carried out in the same manner as in Example 1, except that the catalyst shown in Table 2 was used in powder form and the amount of charge and reaction conditions were changed as shown in Table 3. was carried out. The results are shown in Table 3.

Example 6 Into the same reaction apparatus as in Example 1, 1.2 parts of the catalyst 5C-1 used in Example 1 and 120 parts of ethanol were charged, and the hydrogen pressure was 10 kg/cnl.

After stirring at 130°C for 5 hours, the mixture was cooled to room temperature. Next, 60 parts of terpinolene-4,8-epoxide was added, and after purging the system with nitrogen gas, the mixture was stirred at 140° C. for 16 hours under sealed conditions.

As a result of sampling the reaction product liquid and analyzing it by capillary gas chromatography, it was found that Terpyrun-4,8
- Epoxide conversion was 84.2%, product selectivity was 77.8% for limonene-4-ol, terpinene-4-ol
-1.2% of all, 7.9% of by-product hydrocarbons
, oxygen-containing compounds were 13.1%.

Example 7 In Example 1, the amount of terpyrune-4,8-epoxide charged was 130 parts, no solvent was used, the hydrogen pressure was 5 kg/ctA, and the reaction temperature was 115°C.
Table 3: Examples 12 to 13 The reaction was the same as in Example 1, except that the solvent shown in Table 4 was used instead of ethanol in Example 1, and the reaction conditions were as shown in Table 4. The reaction was carried out in the same manner as in Example 1 except for the following changes. 4th result
Shown in the table.

Table 4 Example 14 In Example 1, 3.0 parts of Raney copper was used as a catalyst, the hydrogen pressure was 5 kg/cal, and the reaction temperature was 1.
The reaction was carried out in the same manner as in Example 1 except that the temperature was 40°C and the reaction time was 15 hours.

As a result, the conversion rate of terpyrune-4.8-epoxide was 93.2%, and the product selectivity was 36.1% for limonen-4-ol and 33.8% for terpinen-4-ol.
Hydrocarbons as by-products are 10.6%, and oxygen-containing compounds are 1%.
It was 9.5%.

Comparative Example 1 In Example 1, the reaction temperature was 65°C and the hydrogen pressure was 20°C.
The reaction was carried out in the same manner as in Example 1, except that the reaction time was 20 hours.

As a result, the conversion rate of terpyrune-4,8-epoxide was 0.3%.

Comparative Example 2 In Example 1, the reaction temperature was 250°C and the reaction time was 4
．． The reaction was carried out in the same manner as in Example 1, except that the reaction time was 5 hours.

As a result, the conversion rate of terpyrune-4,8-epoxide was 100%, the product selectivity was 17.5% for limonene-4-ol, 6.7% for terpinen-4-ol, and the by-product hydrocarbon 45% for oxygen-containing compounds, 14.7% for oxygen-containing compounds
%, other polymers were produced.

〔Effect of the invention〕

According to the invention, terpinolene 4.8-
By isomerizing and/or hydrogenating the epoxide, the corresponding terpene alcohol can be prepared in a single step in high yield.
That is, limonene-4-ol and/or terpinen-4-ol can be obtained, and terpene alcohol can be produced at an extremely low cost without the need for special equipment or water washing steps as seen in the prior art.

Patent applicant Yasushi Oil Industries Co., Ltd. Agent: Patent Attorney Takashi Shirai

Claims (7)

[Claims] (1) A method for producing terpene alcohol in which terpinolene-4,8-epoxide is isomerized and/or hydrogenated using a copper catalyst. (2) The method for producing a terpene alcohol according to claim 1, wherein the copper catalyst is Raney copper. (3) The method for producing a terpene alcohol according to claim 1, wherein the copper catalyst is a copper oxide. (4) The method for producing a terpene alcohol according to claim 1, wherein the copper catalyst is a copper oxide and contains a chromium oxide and/or a zinc oxide. (5) The method for producing a terpene alcohol according to claim 1, 3 or 4, wherein the copper catalyst is supported on a carrier. (6) Isomerization and/or hydrogenation reaction temperature is 70-2
The method for producing terpene alcohol according to claim 1, wherein the temperature is 30°C. (7) The method for producing a terpene alcohol according to claim 1, wherein the isomerization and/or hydrogenation reaction is carried out in the presence of hydrogen gas.