JP2011162446A - Method for producing terpene hydrocarbons - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an environmentally friendly, industrially advantageous method for selectively producing terpene hydrocarbons such as α-terpinene. <P>SOLUTION: The method for producing terpene hydrocarbons comprises bringing limonene or a derivative thereof into contact with zeolite at ≥40°C in an organic solvent in an inert gas atmosphere, thereby selectively producing the terpene hydrocarbons represented by formula (2) (wherein R<SP>1</SP>is hydrogen atom, alkyl group or alkoxy group; R<SP>2</SP>is hydrogen atom, alkyl group or alkoxy group; and the hydrogen atoms in the alkyl group and the alkoxy group are optionally substituted). Here, the zeolite is chosen from faujasite aluminosilicate and mordenite aluminosilicate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing terpene hydrocarbons such as α-terpinene.

α-Terpinene is present in the essential oils of zelkova oil and Lamiaceae plants. This α-terpinene is known to have a venous tonic action in addition to an anti-infective action, a tissue regeneration action, an anti-inflammatory action, a stagnation-removing action, and the like. In addition, α-terpinene has a conjugated double bond in the ring, and when used as a ligand, plane asymmetry occurs, so that it is expected to be used as an asymmetric catalyst.
α-Terpinene is known to be extracted from nature or chemically synthesized. Chemical synthesis methods include, for example, a method of treating α-pinene with concentrated sulfuric acid, a method of dehydrating α-terpineol with oxalic acid, a method of treating linalool and geraniol with concentrated formic acid, and heat treating limonene with dilute sulfuric acid. And the like (for example, see Non-Patent Document 1).

  Patent Document 1 below proposes a method for producing in one step from hemiterpene alcohol using a subcritical or supercritical fluid in a high-temperature and high-pressure state as a reaction solvent, but α-terpinene is a by-product. There is a problem that.

Non-Patent Document 2 below discloses a method of bringing limonene represented by the following formula (R-1) into contact with a synthetic zeolite. In the method of Non-Patent Document 2, d-limonene is reacted in a synthetic zeolite with an aqueous solvent at 90 to 100 ° C. in an air atmosphere, and the product obtained by the method is represented by the following general formula ( These are terpene hydrocarbons represented by R-2) to (R-5), and α-terpinene is not obtained at all.

JP 2005-281265 A.

“Chemical Dictionary 6”, publisher Kyoritsu Publishing Co., Ltd., 1993, 201 pages. The Chemical Society of Japan, No. 1, 1992, 63-67.

  The present inventors have proposed various environmentally harmonious organic synthesis reactions with a low environmental load using zeolite as a catalyst. The present inventors further investigated the organic synthesis reaction with a low environmental load using zeolite as a catalyst, and converted limonene or its derivative into a specific zeolite in an organic solvent in an inert gas atmosphere in a specific temperature range. Upon contact, it was found that terpene hydrocarbons such as α-terpinene were selectively produced, and the present invention was completed.

  That is, an object of the present invention is to provide a method for selectively producing terpene hydrocarbons such as α-terpinene by an industrially advantageous method with a small environmental load.

（式中、Ｒ^１は水素原子、アルキル基又はアルコキシ基を示し、Ｒ^２は水素原子、アルキル基又はアルコキシ基を示す。前記アルキル基及びアルコキシ基は水素原子が置換されていてもよい。）で表されるリモネン又はその誘導体を、不活性ガス雰囲気下に、有機溶媒中でファージャサイト型アルミノシリケート又はモルデナイト型アルミノシリケートから選ばれるゼオライトと４０℃以上で接触させて下記一般式（２）

（式中、Ｒ^１及びＲ^２は前記と同義。）で表されるテルペン炭化水素類を選択的に生成させることを特徴するテルペン炭化水素類の製造方法を提供することにより前記目的を達成したものである。 The present invention relates to the following general formula (1)

(In the formula, R ¹ represents a hydrogen atom, an alkyl group or an alkoxy group, and R ² represents a hydrogen atom, an alkyl group or an alkoxy group. The alkyl group and alkoxy group may be substituted with a hydrogen atom.) The following general formula (2) is obtained by contacting a limonene represented by the formula (1) or a derivative thereof with a zeolite selected from a faujasite type aluminosilicate or a mordenite type aluminosilicate in an organic solvent in an inert gas atmosphere.

(In the formula, R ¹ and R ² are as defined above.) The above object was achieved by providing a method for producing terpene hydrocarbons, which is characterized by selectively producing terpene hydrocarbons. Is.

  According to the present invention, terpene hydrocarbons such as α-terpinene can be selectively produced by contacting with zeolite as a catalyst. This is an industrially advantageous method and has a low environmental impact.

（式中、Ｒ^１は水素原子、アルキル基又はアルコキシ基を示し、Ｒ^２は水素原子、アルキル基又はアルコキシ基を示す。前記アルキル基及びアルコキシ基は水素原子が置換されていてもよい。）で表されるリモネン又はその誘導体を、有機溶媒中でファージャサイト型アルミノシリケート又はモルデナイト型アルミノシリケートから選ばれるゼオライトと４０℃以上で接触させて下記一般式（２）

（式中、Ｒ^１及びＲ^２は前記と同義。）で表されるテルペン炭化水素類を選択的に生成させることを特徴とするものである。 Hereinafter, the present invention will be described based on preferred embodiments.
The production method of the present invention comprises the following general formula (1)

(In the formula, R ¹ represents a hydrogen atom, an alkyl group or an alkoxy group, and R ² represents a hydrogen atom, an alkyl group or an alkoxy group. The alkyl group and alkoxy group may be substituted with a hydrogen atom.) Is contacted with a zeolite selected from ferjasite type aluminosilicate or mordenite type aluminosilicate in an organic solvent at a temperature of 40 ° C. or higher, and the following general formula (2):

(Wherein R ¹ and R ² have the same meanings as described above), and the terpene hydrocarbons represented by the formula are selectively produced.

R ¹ in the general formula (1) is a hydrogen atom, an alkyl group, or an alkoxy group.
Although it does not restrict | limit especially as an alkyl group, A C1-C20 linear or branched alkyl group is preferable, More preferably, a C1-C10 linear or branched alkyl group Is preferred. Specifically, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, n-hexyl group And so on. Although it does not restrict | limit especially as an alkoxy group, For example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. are mentioned.
Among these, alkyl groups are preferred as R ^1, and more preferably a methyl group.

The alkyl group and alkoxy group may be substituted with a hydrogen atom. The type of the substituent is not particularly limited, and examples thereof include an alkyl group, an alkoxy group, and a halogen atom. Here, examples of the alkyl group and alkoxy group as the substituent include the same as the alkyl group and alkoxy group as R ¹ . Moreover, as a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, for example.

R ² in the general formula (1) represents a hydrogen atom, an alkyl group or an alkoxy group, preferably an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 2 carbon atoms. More specifically, examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, and a tert-butyl group. Examples of the alkoxy group include a methoxy group and an ethoxy group.
Among these, as R ² , a methyl group is particularly preferable.

In addition, the alkyl group or alkoxy group of R ² may be substituted with a hydrogen atom. The type of the substituent is not particularly limited, and examples thereof include a halogen atom. Here, examples of the halogen atom include those similar to the halogen atom as the substituent for R ¹ .

R ¹ in the general formula (2) is a group corresponding to R ¹ in the general formula (1), and the type of the group is the same as the group of R ¹ described above. R ² in the general formula (2) is a group corresponding to R ² in the general formula (1), and the type of the group is the same as the group of R ² described above.

  Examples of the limonene represented by the general formula (1) or a derivative thereof used in the present invention include d-limonene, 1-limonene, d / 1-limonene and the like. Among these, d-limonene or a derivative thereof is preferable, and d-limonene is more preferable.

When the limonene represented by the general formula (1) or a derivative thereof is in the d form, an (R) -form α-terpinene represented by the general formula (2) or a terpene hydrocarbon that is a derivative thereof can be obtained. I can do it.
When the limonene represented by the general formula (1) or a derivative thereof is in the l form, the (S) -form α-terpinene represented by the general formula (2) or a terpene hydrocarbon which is a derivative thereof can be obtained. I can do it.
When the limonene represented by the general formula (1) or a derivative thereof is d / l, a racemic α-terpinene represented by the general formula (2) or a terpene hydrocarbon which is a derivative thereof can be obtained. .
When R ² in the general formula (2) is other than a methyl group or a hydrogen atom, the carbon atom to which R ² is bonded is an asymmetric carbon, and the asymmetric carbon is an (R) isomer. (S) body may be sufficient.

  The zeolite used as the catalyst in the present invention is a faujasite type aluminosilicate and / or a mordenite type aluminosilicate (hereinafter sometimes abbreviated as zeolite).

  The ferjasite type aluminosilicate is not limited to a synthetic product but may be a natural product. From the viewpoint of quality, an X-type or Y-type crystalline zeolite is preferably used. These may be partially substituted with alkali metals or alkaline earth metals, but unsubstituted ones, that is, acidic (H type) faujasite type aluminosilicates are more preferably used. Such aluminosilicates may be crystalline or amorphous.

  The mordenite-type aluminosilicate is not limited to a synthetic product but may be a natural product, but synthetic zeolite is preferably used in terms of quality. These may be partially substituted with alkali metal or alkaline earth metal, but unsubstituted one, that is, acidic (H type) mordenite type aluminosilicate is more preferably used. Such an aluminosilicate may be crystalline or amorphous.

  The zeolite used as the catalyst in the present invention is preferably an activated zeolite obtained by burning off organic substances present in the zeolite by heat treatment or the like before use in the reaction. For example, the heat treatment may be performed at 500 ° C. for 1 hour or longer, preferably about 2 to 24 hours, more preferably about 5 hours.

  Note that when the zeolite is reused, the heat treatment may be performed again.

  The amount of zeolite added is not particularly limited, but is 1 to 100 parts by weight, preferably 1 to 20 parts by weight, more preferably 1 part by weight of limonene or a derivative thereof represented by the general formula (1) as a raw material. Is preferably 5 to 20 parts by mass.

  The reaction is represented by the general formula (1) by, for example, dissolving the limonene represented by the general formula (1) as a raw material or a derivative thereof in a solvent, adding zeolite as a powder to the solution, and stirring. A method of contacting limonene or a derivative thereof with zeolite is applicable. In such a reaction, the zeolite is preferably added to a solution in which the raw material is dissolved. Alternatively, the reaction may be carried out by filling a column with zeolite, sending a solution of limonene represented by the general formula (1) or a derivative thereof as a raw material to the column with a pump, and circulating the solution through the column.

  The solvent for dissolving the limonene represented by the general formula (1) or a derivative thereof as a raw material can dissolve the compound represented by the general formula (1), and the compound represented by the general formula (1) A solvent inert to the reaction product is used. For example, n-hexane, cyclohexane, toluene, benzene, acetone, dichloromethane and the like can be mentioned. Of these, cyclohexane is preferably used.

  The reaction is performed in an inert gas atmosphere. The inert gas atmosphere is not particularly limited as long as it does not impair the effects of the present invention. For example, a nitrogen gas atmosphere is preferable. In the present invention, by reacting in an inert gas atmosphere, the selectivity of the target terpene hydrocarbons represented by the general formula (2) is enhanced, and the limonene represented by the general formula (1) remaining unreacted. Alternatively, the number of derivatives thereof can be reduced, and the reaction can be performed efficiently.

  The inert gas used is a terpene hydrocarbon represented by the desired general formula (2) when a calcium chloride tube or an organic solvent such as cyclohexane is used to completely remove moisture. It is preferable from the viewpoint that a product with higher selectivity can be obtained.

In the production method of the present invention, the contact between the limonene represented by the general formula (1) or a derivative thereof and the zeolite is performed at 40 ° C. or higher.
The reason why the contact temperature in the present invention is in the above range is that if the contact temperature is less than 40 ° C., the selectivity of the terpene hydrocarbons represented by the general formula (2) is low, and it remains unreacted. This is because the amount of limonene or a derivative thereof represented by the general formula (1) increases.
In the present invention, it is particularly preferable that the contact between limonene represented by the general formula (1) or a derivative thereof and zeolite is performed at 40 to 80 ° C. because the reaction can be efficiently performed.

  In addition, the reaction is preferably performed in the dark, and by doing so, side reactions during the reaction can be suppressed. The reaction in the dark means that the reaction vessel is blocked from light and allowed to react.

  Although reaction time will not be restrict | limited especially if reaction advances, In many cases, it is 10 minutes or more, Preferably it is about 30 minutes-36 hours. The completion of the reaction can be judged by gas chromatography, for example.

  After completion of the reaction, the zeolite is solid-liquid separated and recovered from the reaction solution by filtration by a conventional method, and the terpene hydrocarbons represented by the general formula (2) are contained by distilling the solvent from the filtrate under reduced pressure. The product is recovered. If necessary, the recovered zeolite is extracted with an organic solvent, the solvent is removed from the extract, and together with the product obtained from the filtrate, the terpene carbonization represented by the general formula (2) is used. A product containing hydrogens may be used. The organic solvent that can be used in the extraction treatment is not particularly limited as long as it can dissolve the reaction product and is inert to the compound. For example, n-hexane, cyclohexane , Toluene, acetone, dichloromethane and the like.

  In addition, as a method for separating the desired terpene hydrocarbons represented by the general formula (2) from by-products, for example, a method of separating by distillation, a method of separating by column chromatography using silica gel or the like, or HPLC And the like can be used.

  EXAMPLES Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited to a following example.

Example 1
Acidified mordenite type aluminosilicate (trade name: JRC-Z-HM20 manufactured by Tosoh Corporation) was activated by heating in air at 500 ° C. for 15 hours using an electric furnace, then cooled to 200 ° C., and then reduced in pressure with a desiccator. The activated zeolite was prepared by returning to room temperature.
Separately, 0.1116 g of d-limonene was added to a 50 ml volumetric flask, and then cyclohexane was added to 50 ml to prepare a cyclohexane solution in which d-limonene was dissolved.
49 ml of the cyclohexane solution in which d-limonene was dissolved as described above was transferred to a flask whose outer surface was covered with aluminum foil, and 2.047 g of the active zeolite prepared above was added thereto, and nitrogen was passed through water. The reaction was carried out with stirring at a temperature of 46 ° C. for 12 hours while bubbling gas through the flask.
After completion of the reaction, the zeolite was separated by filtration, the filtrate was analyzed by gas chromatography mass spectrometry (GC-MS), the components in the filtrate were identified, and the product was quantified by GC. From these results, it was confirmed that the obtained product contained the compounds represented by the following (P2) to (P5) and other compounds in addition to d-limonene (P1).
The ratio of the obtained product is shown in Table 1.

(Example 2)
The reaction was performed in the same manner as in Example 1 except that nitrogen gas passed through the reaction was passed through a cyclohexane solution.
Further, after completion of the reaction, the zeolite was separated by filtration, and the filtrate was analyzed in the same manner as in Example 1. The ratio of the obtained product is shown in Table 1.

(Example 3)
Zeolite activation was carried out in air at 500 ° C. for 7 hours, and nitrogen gas aerated during the reaction was passed through a calcium chloride tube and further passed through a cyclohexane solution. The reaction was performed in the same manner.
Further, after completion of the reaction, the zeolite was separated by filtration, and the filtrate was analyzed in the same manner as in Example 1. The ratio of the obtained product is shown in Table 1.

Example 4
Zeolite activation was carried out in air at 500 ° C. for 5 hours, and nitrogen gas aerated during the reaction was passed through a calcium chloride tube and further passed through a cyclohexane solution. The reaction was performed in the same manner.
Further, after completion of the reaction, the zeolite was separated by filtration, and the filtrate was analyzed in the same manner as in Example 1. The ratio of the obtained product is shown in Table 1.

(Example 5)
Zeolite activation was performed in air at 500 ° C. for 2 hours, and nitrogen gas aerated during the reaction was passed through a calcium chloride tube and further passed through a cyclohexane solution. The reaction was performed in the same manner.
Further, after completion of the reaction, the zeolite was separated by filtration, and the filtrate was analyzed in the same manner as in Example 1. The ratio of the obtained product is shown in Table 1.

(Comparative Example 1)
The reaction was conducted in the same manner as in Example 3 except that the reaction temperature was 35 ° C.
Further, after completion of the reaction, the zeolite was separated by filtration, and the filtrate was analyzed in the same manner as in Example 1. The ratio of the obtained product is shown in Table 1.

(Comparative Example 2)
The reaction was performed in the same manner as in Example 3 except that air through which water was passed was used as the nitrogen gas vented during the reaction.
Further, after completion of the reaction, the zeolite was separated by filtration, and the filtrate was analyzed in the same manner as in Example 1. The ratio of the obtained product is shown in Table 1.

注１）「窒素^（１」は、水中を通過させた窒素ガスを示す。「窒素^（２」は、シクロヘキサン溶液中を通過させた窒素ガスを示す。「窒素^（３」は、塩化カルシウム管を通過させた後、更にシクロヘキサン溶液中を通過させた窒素ガスを示す。「空気^（４」は、水中を通過させた空気を示す。
注２）「基質^１）」は、原料として用いたｄ−リモネンを示す。
注３）「ろ液の各成分の比率^１）」は、ＧＣ分析でのピーク面積の比を示す。

Note 1) “Nitrogen ⁽¹ ”) indicates nitrogen gas passed through water. “Nitrogen ⁽² ”) indicates nitrogen gas passed through cyclohexane solution. “Nitrogen ⁽³ ”) indicates calcium chloride tube. Nitrogen gas that has been further passed through the cyclohexane solution after passing through, “air ⁽⁴ ”) indicates air that has passed through water.
Note 2) “Substrate ¹⁾ ” indicates d-limonene used as a raw material.
Note 3) “Ratio of each component of the filtrate ¹⁾ ” indicates the ratio of peak areas in GC analysis.

  From the results in Table 1, it can be seen that the target α-terpinene (P1) is produced as a main component in addition to the starting material d-limonene in the reaction solution after completion of the reaction. In contrast, α-terpinene (P1) is also produced in the comparative example, but the selectivity to α-terpinene (P1) is lower than in the examples, and unreacted raw materials are also present. It can be seen that many remain.

  According to the present invention, terpene hydrocarbons such as α-terpinene can be selectively produced simply by contacting with zeolite as a catalyst. It is industrially advantageous and has a low environmental impact.

Claims (3)

The following general formula (1)

(In the formula, R ¹ represents a hydrogen atom, an alkyl group or an alkoxy group, and R ² represents a hydrogen atom, an alkyl group or an alkoxy group. The alkyl group and alkoxy group may be substituted with a hydrogen atom.) The following general formula (2) is obtained by contacting a limonene represented by the formula (1) or a derivative thereof with a zeolite selected from a faujasite type aluminosilicate or a mordenite type aluminosilicate in an organic solvent in an inert gas atmosphere.

(Wherein R ¹ and R ² are as defined above), a method for producing terpene hydrocarbons which is selectively produced.   The method for producing terpene hydrocarbons according to claim 1, wherein the zeolite is an acidic mordenite-type aluminosilicate.   The method for producing terpene hydrocarbons according to claim 1 or 2, wherein the compound represented by the general formula (1) is limonene, and the terpene hydrocarbons to be selectively produced are α-terpinenes. .