JP2015209403A - Alicyclic triketone compound having bis-spironorbornane structure, and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alicyclic triketone compound useful as an intermediate of medicine, an intermediate material for industrial products, and an additive; and to provide a method for producing the same.SOLUTION: Problems are solved through: the synthesis of an alicyclic triketone compound having a bis-spironorbornane structure represented by the following general formula (1); the identification of a product; the review of a production method; and the analysis of an intermediate. In the formula, one of Rand Ris ketone and the other thereof is -H; one of Rand Ris ketone and the other thereof is -H; Rand Rare each independently the one selected from the group consisting of a hydrogen atom, 1-10C alkyl group, and a fluorine atom; and n is an integer of 2 to 5.

Description

  The present invention relates to an alicyclic triketone compound which is a compound useful as an intermediate raw material and additive for pharmaceutical intermediates and industrial products, and a method for producing the same.

  An alicyclic diketone compound or an alicyclic triketone compound is a compound useful as an intermediate material and additive for pharmaceutical intermediates and industrial products by utilizing the reactivity of the C═O group. Diversification is desired. For example, an efficient method for producing 2,2-bis (4-oxocyclohexyl) propane, which is useful as an intermediate for antioxidants, heat stabilizers, and the like, and derivatives thereof has been developed. (Patent Documents 1 to 3)

JP-A-4-59742 Japanese Patent Laid-Open No. 11-158108 JP 11-199539 A JP 2011-162479 A

  An object of the present invention is mainly to provide an alicyclic triketone compound having a bisspironorbornane structure and a method for producing the same.

  As a result of intensive studies to achieve the above object, the present inventors have used a norbornene compound represented by the following general formula (2) as a starting material, and this is a bisspiro represented by the following general formula (3). It is found that an alicyclic triketone compound having a bisspironorbornane structure represented by the following general formula (1) can be provided by converting it to an alicyclic diol compound having a norbornane structure and then oxidizing the compound. The invention has been completed.

（Ｒ^１、Ｒ^２の何れか一方がケトン、他方が−Ｈ、Ｒ^３、Ｒ^４の何れか一方がケトン、他方が−Ｈであり、Ｒ^５、Ｒ^６はそれぞれ独立に、水素原子、炭素数１〜１０のアルキル基及びフッ素原子よりなる群から選択される１種を示し、ｎは２〜５の整数である） That is, the first of the present invention relates to an alicyclic triketone compound having a bisspironorbornane structure represented by the following formula (1).

(One of R ¹ and R ² is a ketone, the other is —H, R ³ , and R ⁴ are ketones and the other is —H, and R ⁵ and R ⁶ are each independently a hydrogen atom, 1 type selected from the group consisting of an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n is an integer of 2 to 5)

  That is, the second of the present invention relates to the first alicyclic triketone compound of the present invention, wherein in the general formula (1), n is 2 or 3.

  That is, the third of the present invention relates to the first alicyclic triketone compound of the present invention, wherein n is 2 in the general formula (1).

（Ｒ^１、Ｒ^２はそれぞれ独立に、水素原子、炭素数１〜１０のアルキル基及びフッ素原子よりなる群から選択される１種を示し、ｎは２〜５の整数を示す。）

（Ｒ^１、Ｒ^２のいずれか一方は−ＯＨ、他方は−Ｈであり、Ｒ^３、Ｒ^４のいずれか一方は−ＯＨ、他方は−Ｈであり、Ｒ^５、Ｒ^６はそれぞれ独立に、水素原子、炭素数１〜１０のアルキル基及びフッ素原子よりなる群から選択される１種を示し、ｎは２〜５の整数を示す。）

（Ｒ^１、Ｒ^２の何れか一方がケトン、他方が−Ｈ、Ｒ^３、Ｒ^４の何れか一方がケトン、他方が−Ｈであり、Ｒ^５、Ｒ^６はそれぞれ独立に、水素原子、炭素数１〜１０のアルキル基及びフッ素原子よりなる群から選択される１種を示し、ｎは２〜５の整数である） That is, the fourth aspect of the present invention uses a norbornene compound represented by the following general formula (2) as a raw material to produce an alicyclic diol compound having a bisspironorbornane structure represented by the following general formula (3). Next, by oxidizing the hydroxyl group, an alicyclic triketone compound having a bisspirononorbornane structure represented by the following general formula (1) is produced, which is represented by the following general formula (1). The present invention relates to a method for producing an alicyclic triketone compound.

(R ¹ and R ² each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n represents an integer of 2 to 5)

(One of R ¹ and R ² is —OH, the other is —H, one of R ³ and R ⁴ is —OH, the other is —H, and R ⁵ and R ⁶ are each independently , A hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n represents an integer of 2 to 5.)

(One of R ¹ and R ² is a ketone, the other is —H, R ³ , and R ⁴ are ketones and the other is —H, and R ⁵ and R ⁶ are each independently a hydrogen atom, 1 type selected from the group consisting of an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n is an integer of 2 to 5)

  That is, a fifth aspect of the present invention relates to the fourth method for producing an alicyclic triketone compound according to the present invention, wherein n is 2 or 3 in the general formula (1).

  That is, the fifth aspect of the present invention relates to the fourth method for producing an alicyclic triketone compound according to the present invention, wherein n is 2 in the general formula (1).

  According to the present invention, an alicyclic triketone compound having a bisspironorbornane structure, a production method thereof, and a reaction intermediate are provided. The compound is useful as an intermediate material and additive for pharmaceutical intermediates and industrial products.

2 is a chart showing an IR spectrum of an alicyclic diol compound of general formula (6) obtained in Example 1. FIG. 2 is a chart showing a ¹ H-NMR spectrum of an alicyclic diol compound of the general formula (6) obtained in Example 1. FIG. 2 is a chart showing an FD-MS spectrum of an alicyclic diol compound of the general formula (6) obtained in Example 1. FIG. 2 is a chart showing an IR spectrum of an alicyclic triketone compound of the general formula (7) obtained in Example 1. 2 is a chart showing a ¹ H-NMR (CDCl ₃ ) spectrum of an alicyclic triketone compound of the general formula (7) obtained in Example 1. FIG. 2 is a chart showing an FD-MS spectrum of an alicyclic triketone compound of the general formula (7) obtained in Example 1. FIG.

(Structure of the alicyclic triketone compound of the present invention)
The alicyclic triketone compound according to the present invention is an alicyclic triketone compound represented by the following general formula (1).

（Ｒ^１、Ｒ^２の何れか一方がケトン、他方が−Ｈ；Ｒ^３、Ｒ^４の何れか一方がケトン、他方が−Ｈであり、Ｒ^５、Ｒ^６はそれぞれ独立に、水素原子、炭素数１〜１０のアルキル基及びフッ素原子よりなる群から選択される１種を示し、ｎは２〜５の整数である）

(One of R ¹ and R ² is a ketone, the other is -H; one of R ³ and R ⁴ is a ketone, and the other is -H, and R ⁵ and R ⁶ are each independently a hydrogen atom, 1 type selected from the group consisting of an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n is an integer of 2 to 5)

  The alicyclic triketone compound according to the present invention has, as a basic structure, a bisspironorbornane structure having a norbornane ring at the symmetrical position of cycloalkanone, strong symmetry, and no free-rotating carbon-carbon bond. It is characterized by having. To date, there are no known production examples of alicyclic triketone compounds having the basic structure.

  The general formula (1) collectively represents a plurality of isomers generated from the conformational relationship between the cycloalkanone ring and the norbornane ring and between the norbornane ring and the carbonyl group.

（ｎ＝２または３、Ｒ^１＝Ｒ^２＝−Ｈ） (Method for producing alicyclic triketone compound of the present invention)
The production of the alicyclic triketone compound according to the present invention is carried out by using a bisspironorbornene compound having a structure corresponding thereto, that is, a bisspirononorbornene compound represented by the general formula (2) as a raw material, and the unsaturated compound in the compound. It is preferable to produce it through chemical modification of the bond. The manufacturing method of the following general formula (2) is disclosed in Patent Document 4 (paragraphs [0119] to [0132]) by the present applicant.

(N = 2 or 3, R ¹ = R ² = −H)

The compound having a bisspirornorbornene structure produced by the production method disclosed in Patent Document 4 (see also the examples below) can be used as it is without isolation, After separation and purification, it may be used in subsequent reactions.
A compound having a bisspirononorbornene structure having cycloheptanone or cyclooctanone as a skeleton can be synthesized in the same manner as described above.

  Hereinafter, a method for producing the alicyclic triketone compound according to the present invention from the above bisspironorbornene compound will be described.

  The synthesis of the alicyclic triketone compound according to the present invention is preferably obtained by obtaining a diol compound from the corresponding bisspirononorbornene compound as a raw material and oxidizing the hydroxyl group.

(Method for producing alicyclic diol compound)
In order to produce an alicyclic diol compound, which is a synthesis intermediate of the alicyclic triketone according to the present invention, from the bisspirononorbornene compound, a carbon-carbon double bond is hydroborated to obtain a diboron compound. An alicyclic diol compound is obtained by performing an oxidation reaction using a known method. Among known oxidation methods, a method using a combination of inorganic bases and hydrogen peroxide is simple and preferable.

  Hydroboration can be carried out using a borane complex. The borane complex may be appropriately selected from known complexes. From the viewpoint of yield, a borane / tetrahydrofuran complex is preferable.

  Examples of inorganic bases used in the oxidation reaction include sodium hydroxide, potassium hydroxide, lithium hydroxide, calcium hydroxide, barium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate, and lithium carbonate. And inorganic bases such as sodium hydrogen carbonate, potassium hydrogen carbonate, and lithium hydrogen carbonate. Among these, it is preferable to use sodium hydroxide, potassium hydroxide, or lithium hydroxide from the viewpoint of reaction yield, reaction temperature, simplicity of operation, economy, and the like.

  A commercially available hydrogen peroxide solution can be used as it is. The amount of hydrogen peroxide to be used is preferably in the range of 1 to 5 times mol, more preferably in the range of 1 to 2 times mol for the carbon-carbon unsaturated bond in the bisspirononorbornene compound of the raw material compound. More preferred. When the amount is less than 1 mol, the reaction does not proceed sufficiently. When the amount exceeds 5 mol, side reactions such as oxidation of the produced alicyclic diol compound proceed and the yield tends to decrease.

  The reaction temperature for hydroboration of the bisspirononorbornene compound is preferably in the range of −80 to 80 ° C., more preferably in the range of −20 to 50 ° C. When the temperature is lower than -80 ° C, the reaction rate is extremely low and the reaction efficiency is poor. When the temperature is higher than 80 ° C, decomposition of raw materials and products may occur.

  The reaction temperature for the oxidation of the alicyclic diboron compound is preferably in the range of 20 to 100 ° C. When the temperature is lower than 20 ° C, the reaction rate is extremely low and the reaction efficiency is poor. When the temperature is higher than 100 ° C, the raw materials and products may be decomposed.

(Method for producing alicyclic triketone compound)
Subsequently, the obtained alicyclic diol compound is oxidized to obtain the alicyclic triketone compound according to the present invention. This reaction is an oxidation reaction of a secondary alcohol to a ketone, and a known reaction can be used. As a known method, an oxidation method using chromic acid (Jones oxidation, Sallet oxidation, Collins oxidation, PCC oxidation, PDC oxidation), an oxidation method using dimethyl sulfoxide (swarnation), a hypervalent iodine compound was used. And des-martin oxidation. Particularly preferred is Dess-Martin oxidation.

  The alicyclic triketone compound having a bisspironorbornane structure according to the present invention is useful as a pharmaceutical intermediate, an intermediate material for industrial products, an additive, and the like.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

  In addition, in the following, identification of the molecular structure of the compound obtained in each Example is performed using an IR spectrophotometer (manufactured by JASCO Corporation, trade names: FT / IR-460, FT / IR-4100), NMR spectroscopy. IR machine (product name: UNITY INOVA-600 and JEOL Ltd. JNM-Lambda500) and FD-MS mass spectrometer (product of JEOL Ltd., product name: JMS-700V) , NMR, and FD-MS spectra were measured.

(Synthesis of raw material "cyclopentanone type bisspironorbornene")
(Synthesis Example 1)
<First step>
First, 30.86 g (378.5 mmol) of dimethylamine hydrochloride was added to a 1 L three-necked flask. Next, 12.3 g (385 mmol) of paraformaldehyde, 23.9 g (385 mmol) of ethylene glycol, and 12.95 g (154 mmol) of cyclopentanone were further added to the three-necked flask. Next, after adding 16.2 g (165 mmol) of methylcyclohexane to the three-necked flask, 0.4 g of 35 mass% hydrochloric acid (HCl: 3.85 mmol) was added to obtain a first mixed solution. The acid (HCl) content in the first mixed solution is 0.025 molar equivalent (3.85 [mol amount of HCl] / 154 [cyclopentanone] based on the ketone group in cyclopentanone. Molar amount] = 0.025).

で表されるマンニッヒ塩基を含有する反応液を得た。 Next, the inside of the three-necked flask was purged with nitrogen, the temperature in the three-necked flask was set at 85 ° C. at normal pressure (0.1 MPa), and the first mixed solution was heated and stirred for 8 hours to obtain the following chemical formula (5) :

The reaction liquid containing the Mannich base represented by this was obtained.

<Second step>
Next, after cooling the reaction solution in the three-necked flask to 50 ° C., methanol (250 ml) and 4.17 g of a 50 mass% dimethylamine aqueous solution (dimethylamine: 46) with respect to the reaction solution in the three-necked flask. 0.2 mmol) and 30.5 g (461.5 mmol) of cyclopentadiene were added to obtain a second mixed solution. Next, the inside of the three-necked flask is replaced with nitrogen, the temperature in the three-necked flask is set to 65 ° C. at normal pressure (0.1 MPa), and the second mixed solution is heated and stirred at 65 ° C. for 5 hours to form a compound. I let you.

  Next, the second mixed liquid in the three-necked flask was concentrated by azeotropic distillation of methylcyclohexane and methanol, and 100 mL of the liquid was removed from the second mixed liquid. By removing 100 mL of such liquid, most of methylcyclohexane (75% by mass with respect to the total amount of methylcyclohexane in the second mixed solution before concentration) was removed from the second mixed solution. Next, after the said 2nd liquid mixture after methylcyclohexane removal was cooled on -20 degreeC temperature conditions for 12 hours, the crystal | crystallization was deposited, Then, it filtered under reduced pressure and the crystal | crystallization was obtained. The crystal thus obtained was washed three times with 20 mL of -20 ° C. methanol, and then evaporated to remove the methanol to obtain 17.4 g (yield 47) of the product. %)Obtained.

で表される５−ノルボルネン−２−スピロ−２’−シクロペンタノン−５’−スピロ−２’’−５’’−ノルボルネンであることが確認された。 In order to confirm the structure of the compound thus obtained, IR and NMR ( ¹ H-NMR and ¹³ C-NMR) measurements were performed. The following chemical formula (5):

It was confirmed that it was 5-norbornene-2-spiro-2′-cyclopentanone-5′-spiro-2 ″ -5 ″ -norbornene represented by

で表わされるノルボルネン化合物（４．８ｇ、２０．０ｍｍｏｌ）を仕込んで混合液を得た後、前記容器を密閉して内部の雰囲気を窒素置換した。次に、前記容器を氷浴で冷却しながらボラン‐テトラヒドロフランコンプレックス（０．９ｍｏｌ／Ｌ、４９ｍＬ、４４ｍｍｏｌ）を加え、２０℃の温度条件で前記混合液を２時間攪拌して反応液を得た。次いで、前記容器を氷浴で冷却しながら水酸化ナトリウム溶液（２ｍｏｌ／Ｌ、１５ｍＬ、３０ｍｍｏｌ）及び３０質量％過酸化水素水（１５ｍＬ）を加え、６０℃の温度条件で３時間撹拌して反応液を得た。その後、ジエチルエーテル（５０ｍＬ）を加え、飽和食塩水（５０ｍＬ）で２回洗浄した。有機層に無水硫酸ナトリウムを加え、乾燥させたのち濾液をエバポレーターで濃縮して有機溶媒を留去して生成物を得た（収量５．２８ｇ、収率９５．５％）。 Example 1
(Synthesis of alicyclic diol)
In a 200 mL two-necked flask, tetrahydrofuran (100 mL) and the following chemical formula (5):

Was added to obtain a mixed solution, and the vessel was sealed and the atmosphere inside was replaced with nitrogen. Next, while cooling the vessel in an ice bath, borane-tetrahydrofuran complex (0.9 mol / L, 49 mL, 44 mmol) was added, and the mixture was stirred at 20 ° C. for 2 hours to obtain a reaction solution. . Next, sodium hydroxide solution (2 mol / L, 15 mL, 30 mmol) and 30% by mass hydrogen peroxide (15 mL) were added while cooling the vessel in an ice bath, and the mixture was stirred for 3 hours at 60 ° C. for reaction. A liquid was obtained. Thereafter, diethyl ether (50 mL) was added, and the mixture was washed twice with saturated brine (50 mL). After adding anhydrous sodium sulfate to the organic layer and drying, the filtrate was concentrated with an evaporator and the organic solvent was distilled off to obtain the product (yield 5.28 g, yield 95.5%).

（Ｒ^１、Ｒ^２のいずれか一方は−ＯＨ、他方は−Ｈであり、Ｒ^３、Ｒ^４のいずれか一方は−ＯＨ、他方は−Ｈである。）
で表される脂環式ジオール（目的化合物の合成中間体）であることが確認された。 In order to confirm the structure of the compound contained in the product thus obtained, IR, NMR, and FD-MS measurements were performed. As a result of such measurement, FIG. 1 shows an IR spectrum, FIG. 2 shows a ¹ H-NMR (CD ₃ OD) spectrum, and FIG. 3 shows a spectrum of FD-MS measurement. As is clear from the results shown in FIGS. 1 to 3, the compound obtained in Example 1 is represented by the following general formula (6):

(One of R ¹ and R ² is —OH, the other is —H, one of R ³ and R ⁴ is —OH, and the other is —H.)
It was confirmed that it is an alicyclic diol represented by the formula (a synthetic intermediate of the target compound).

（Ｒ^１、Ｒ^２のいずれか一方は−ＯＨ、他方は−Ｈであり、Ｒ^３、Ｒ^４のいずれか一方は−ＯＨ、他方は−Ｈである。）
で表わされる脂環式ジオール （１４０．２ｍｇ、０．５０ｍｍｏｌ）及びデス−マーチンペルヨージナン（４６７．２ｍｇ、１．１ｍｍｏｌ）を仕込んで混合液を得た後、２０℃の温度条件で前記混合液を１時間攪拌して反応液を得た。次に、ジエチルエーテル（１０ｍＬ）、飽和重曹水（１０ｍＬ）、亜硫酸ナトリウム（７００ｍｇ）を加えて過剰量のデス−マーチンペルヨージナンを分解した。次いで、飽和重曹水（１０ｍＬ）及び水（１０ｍＬ）で有機層を洗浄した。その後、無水硫酸ナトリウムを加え、乾燥させたのち濾液をエバポレーターで濃縮して有機溶媒を留去して生成物を得た。 (Synthesis of alicyclic triketone)
In a 50 mL flask, methylene chloride (10 mL), the following general formula (6) obtained by the above reaction:

(One of R ¹ and R ² is —OH, the other is —H, one of R ³ and R ⁴ is —OH, and the other is —H.)
And a Dess-Martin periodinane (467.2 mg, 1.1 mmol) was added to obtain a mixed solution, and then the mixture was mixed at a temperature of 20 ° C. The solution was stirred for 1 hour to obtain a reaction solution. Next, diethyl ether (10 mL), saturated aqueous sodium hydrogen carbonate (10 mL), and sodium sulfite (700 mg) were added to decompose an excessive amount of Dess-Martin periodinane. Then, the organic layer was washed with saturated aqueous sodium hydrogen carbonate (10 mL) and water (10 mL). Thereafter, anhydrous sodium sulfate was added and dried, and then the filtrate was concentrated with an evaporator to distill off the organic solvent to obtain a product.

（Ｒ^１、Ｒ^２のいずれかはケトン、他方は−Ｈであり、Ｒ^３、Ｒ^４のいずれかはケトン、他方は−Ｈである。）
で表される脂環式トリケトン（目的化合物）であることが確認された。 In order to confirm the structure of the compound contained in the product thus obtained, IR, NMR, and FD-MS measurements were performed. As a result of such measurement, FIG. 4 shows an IR spectrum, FIG. 5 shows a ¹ H-NMR (CDCl ₃ ) spectrum, and FIG. 6 shows a spectrum of FD-MS measurement. As is clear from the results shown in FIGS. 4 to 6, the compound obtained in Example 1 is represented by the following general formula (7):

(One of R ¹ and R ² is a ketone, the other is —H, one of R ³ and R ⁴ is a ketone, and the other is —H.)
It was confirmed that it is an alicyclic triketone (target compound) represented by:

(Synthesis of cyclohexanone type bisspironorbornene):
It was synthesized according to Example 2 described in Patent Document 4 (paragraphs [0126] to [0132]) (yield 56%).

(Synthesis of alicyclic triketone compound):
Using the cyclohexanone type bisspironorbornene as a raw material, an alicyclic triketone having a cyclohexanone type bisspironorbornane structure is synthesized in the same manner as described above, and the product is represented by the chemical formula (8) by IR, NMR, and MS spectra. It can confirm that it is an alicyclic triketone compound structure represented by this.

（Ｒ^１、Ｒ^２のいずれか一方はケトン、他方は−Ｈであり、Ｒ^３、Ｒ^４のいずれか一方はケトン、他方は−Ｈである。）

(One of R ¹ and R ² is a ketone, the other is —H, one of R ³ and R ⁴ is a ketone, and the other is —H.)

(Synthesis of other alicyclic triketone compounds):
In the general formula (1), when the cycloalkanone ring is n = 4 (cycloheptanone ring) or 5 (cyclooctanone ring), the cycloheptanone type or cyclooctanone type is the same as the above method. An alicyclic triketone compound is synthesized through a diol compound having the bisspirononorbornane structure using the compound having the bisspirononorbornene structure.

  The alicyclic triketone compound having a bisspironorbornane structure according to the present invention is useful as a pharmaceutical intermediate, an intermediate material for industrial products, an additive, and the like.

Claims (6)

An alicyclic triketone compound represented by the following general formula (1).

(One of R ¹ and R ² is a ketone, the other is —H, R ³ , and R ⁴ are ketones and the other is —H, and R ⁵ and R ⁶ are each independently a hydrogen atom, 1 type selected from the group consisting of an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n is an integer of 2 to 5)   The alicyclic triketone compound according to claim 1, wherein n is 2 or 3 in the general formula (1).   The alicyclic triketone compound according to claim 1, wherein n = 2 in the general formula represented by the general formula (1). By using an alicyclic compound represented by the following general formula (2) as a raw material, an alicyclic diol compound represented by the following general formula (3) is produced, and then by oxidizing the hydroxyl group, The manufacturing method of the alicyclic triketone compound represented by the following general formula (1) characterized by manufacturing the alicyclic triketone compound represented by General formula (1).

(R ¹ and R ² each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n represents an integer of 2 to 5)

(One of R ¹ and R ² is —OH, the other is —H, one of R ³ and R ⁴ is —OH, the other is —H, and R ⁵ and R ⁶ are each independently , A hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n represents an integer of 2 to 5.)

(One of R ¹ and R ² is a ketone, the other is —H, R ³ , and R ⁴ are ketones and the other is —H, and R ⁵ and R ⁶ are each independently a hydrogen atom, 1 type selected from the group consisting of an alkyl group having 1 to 10 carbon atoms and a fluorine atom, and n is an integer of 2 to 5)   In the said General formula (1), n is 2 or 3, The manufacturing method of the alicyclic triketone compound of Claim 4 characterized by the above-mentioned.   In the said General formula (1), n is 2, The manufacturing method of the alicyclic triketone compound of Claim 4 characterized by the above-mentioned.

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