JP6859761B2 - Method for producing lactone compound - Google Patents

Description

The present invention relates to a method for producing a lactone compound.

Several methods have been proposed as methods for producing a lactone compound having an unsaturated bond. (For example, Patent Document 1, Patent Document 2, Non-Patent Document 1, Non-Patent Document 2).
Patent Document 1 and Non-Patent Document 1 disclose a method for reacting trans-2-butene 1,4-diol with triethyl orthoacetate under an acid catalyst. Patent Document 2 discloses a method for reacting 3- (2-hydroxyethyl) -butyrolactone under an acid catalyst. Non-Patent Document 2 discloses a method in which 1,4-diacetoxycyclopenta-2-ene is hydrolyzed under a lipase catalyst and then reacted with triethyl orthoacetate under an acid catalyst.

Japanese Unexamined Patent Publication No. 50-111061 U.S. Pat. No. 4,837,346

Chemistry Letters, 1974, 3,741-742 Journal of the Chemical Society, Chemical Communications, 1986, 16, 1298-1299

However, the methods described in Patent Document 1 and Non-Patent Document 1 use trans-2-butene 1,4-diol, which is difficult to obtain, as a raw material, and easily available cis-2-butene-1, The yield of 4-diol is low. The method described in Patent Document 2 uses 3- (2-hydroxyethyl) -butyrolactone as a raw material, but it is not suitable for industrial production because it cannot be obtained at low cost. Further, in the method described in Non-Patent Document 2, the acetoxy group is first hydrolyzed in an aqueous solvent, and then the obtained alcohol is further reacted with triethyl orthoacetate. Not suitable.
Therefore, an object of the present invention is to provide a method capable of efficiently producing a lactone compound in a short process from an inexpensive and easily available raw material.

式（１）中、Ｒ^１及びＲ^２は炭素数１〜２０の炭化水素基を表し、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７及びＲ^８は水素または置換基を有していてもよい炭素数１〜２０の炭化水素基を表し、これらの炭化水素基は、不飽和結合を有していても、エーテル結合を有していてもよい。シス体、トランス体、シス−トランス異性体混合物のいずれでもよい。

式（２）中、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７及びＲ^８は水素または置換基を有していてもよい炭素数１〜２０の炭化水素基を表し、不飽和結合を有していても、エーテル結合を有していてもよい。 The present invention is a method for producing a lactone compound represented by the following formula (2) by reacting a diester compound represented by the following formula (1) with an orthocarboxylic acid ester in the presence of a Lewis acid catalyst. ..

In formula (1), R ¹ and R ² represent hydrocarbon groups having 1 to 20 carbon atoms, and R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ have hydrogen or substituents. It represents a hydrocarbon group having 1 to 20 carbon atoms, and these hydrocarbon groups may have an unsaturated bond or an ether bond. It may be a cis form, a trans form, or a mixture of cis-trans isomers.

In formula (2), R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ represent hydrogen or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent and are unsaturated bonds. Or may have an ether bond.

According to the present invention, a lactone compound can be efficiently produced in a single step.

The method for producing the lactone compound according to the present invention will be described in detail below.
(1) Diester compound The diester compound used in the present invention is a compound represented by the formula (1).
In formula (1), R ¹ and R ² represent hydrocarbon groups having 1 to 20 carbon atoms. If R ¹ and R ² are hydrocarbon groups, their types and structures are not limited. In formula (1), R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ represent hydrogen or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. If R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are hydrogen or hydrocarbon groups, their types and structures are not limited. These hydrocarbon groups may have a linear, branched, and ring structure, may have an unsaturated bond, or may have an ether bond.

The purity of the diester compound used in the present invention is not particularly limited, but is preferably 50% by mass or more, more preferably 70% by mass or more, and further preferably 85% by mass or more. It is preferably 90% by mass or more, and most preferably 95% by mass or more. By using a diester compound having a purity of 50% by mass or more, the amount of the lactone compound produced per reaction volume can be increased.

The diester compound may be a cis compound, a trans isomer, or a mixture of cis-trans isomers, and the isomer ratio thereof is not particularly limited, but it is preferable that the diester compound contains 50% or more of the trans isomer, and 70% or more. More preferably, it is most preferably 85% or more. By increasing the content of the trans compound, the lactone compound can be produced more easily.
Examples of the hydrocarbon group include an alkyl group, an alkenyl group, an alkynyl group, and an aryl group.

From the viewpoint of availability of the diester compound represented by the formula (1), ^{the carbon numbers of R 1} and R ² are 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 4. Specific examples thereof include a methyl group, an ethyl group and an n-butyl group. ^{Further, R 3} , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ of the diester compound represented by the formula (1) are hydrogen or hydrocarbons having 1 to 20 carbon atoms which may have a substituent. It is a group, and hydrogen is preferable from the viewpoint of availability, and the number of carbon atoms in the case of a hydrocarbon group is 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 4. Hydrogen is most preferred. Examples of the compound represented by the formula (1) include 1,4-diacetoxy-2-butene and 1,4-bis (butyryloxy) -2-butene. Since lactone compounds can be synthesized efficiently, 1,4-acetoxy-2- ^{, in which R 1} and R ² are methyl groups and R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 are hydrogen.} Butene is preferred.
As the diester compound represented by the formula (1), a commercially available one can be used, and a compound obtained by producing by a known method or the like can also be used. Further, as the compound represented by the formula (1), one kind may be used, or two or more kinds may be used in combination.

(2) Orthocarboxylic Acid Ester The purity of the orthocarboxylic acid ester used in the present invention is not particularly limited, but is preferably 50% by mass or more, more preferably 70% by mass or more. It is more preferably 85% by mass or more, particularly preferably 90% by mass or more, and most preferably 95% by mass or more. By using an orthocarboxylic acid ester compound having a purity of 50% by mass or more, the amount of the lactone compound produced per reaction volume can be increased.

The type and structure of the orthocarboxylic acid ester are not particularly limited. For example, an orthocarboxylic acid ester can be represented as "R ⁹ C (OR ¹⁰ ) (OR ¹¹ ) (OR ¹² )", with R ⁹ , R ¹⁰ , R ¹¹ and R ¹² having substituents. It represents a hydrocarbon group having 1 to 20 carbon atoms. This hydrocarbon group may have a linear, branched, and ring structure, or may have an unsaturated bond. The fact that it may have a substituent means that it may contain one or more of arbitrary bonds, functional groups, atoms, and the like. Examples of the substituent include an ester bond, a siloxane bond, an amide bond, a sulfide bond, a disulfide bond, an ether bond, a nitro group, a cyano group, a carbonyl group, a sulfonyl group, a halogen, silicon, phosphorus and the like.

Examples of the hydrocarbon group include an alkyl group, an alkenyl group, an alkynyl group, an aryl group and the like. From the viewpoint of availability of the orthocarboxylic acid ester, ^{the carbon number of R 9} is 1 to 20, more preferably 1 to 10. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group and an n-butyl group. From the viewpoint of removing by-produced alcohol, ^{the carbon numbers of R 10} , R ¹¹ and R ¹² are 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 6. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group and a phenyl group. R ¹⁰ , R ¹¹ and R ¹² may be the same or different, but are preferably the same from the viewpoint of simplifying the manufacturing process.

Specifically, examples of the orthocarboxylic acid ester include trimethyl orthoacetate, triethyl orthoacetate, tri-n-butyl orthoacetate, trimethyl orthopropionate, and the like, with trimethyl orthoacetate and triethyl orthoacetate being more preferable.
As the orthocarboxylic acid ester, a commercially available one can be used, or one obtained by manufacturing by a known method or the like can also be used. Further, the orthocarboxylic acid ester may be used alone or in combination of two or more.

(3) Catalyst In the present invention, the presence of a catalyst means that the catalyst needs to be present at least in a part of the reaction steps, and does not have to be present at all stages of the reaction step. In the present invention, the addition of a catalyst into the reaction system satisfies the requirements in the presence. For example, even if some change occurs in the catalyst in the reaction step after the catalyst is added into the reaction system, it is included in the presence of the catalyst.

The Lewis acid used as a catalyst in the production of the lactone compound is not particularly limited, but is preferably a metal compound, and the ligand is a basic, neutral, or weakly acidic metal compound. Is even more preferable. The metal element contained in the metal compound is not particularly limited, and examples thereof include tin, titanium, zirconium, and aluminum. The ligand is not particularly limited, and examples thereof include an alkyl group, an alkoxy group, a carboxy group, and acetylacetonato. By adjusting the acidity of the ligand, side reactions can be suppressed. The metal compound in which the ligand is basic, neutral, or weakly acidic is not particularly limited, but dialkyltin oxide and zirconium acetylacetonate are preferable, and dibutyltin oxide is more preferable.
As these catalysts, commercially available catalysts can be used, or those produced by a known method or the like can be used. Further, these catalysts may be used alone or in combination of two or more.

(4) Additive In the present invention, the presence of an additive means that the additive may be present at at least a part of the reaction step, and does not have to be always present at all steps of the reaction step. .. In the present invention, if an additive is added into the reaction system, the requirement in the presence is satisfied. For example, even if any change occurs in the additive in the reaction step after the additive is added into the reaction system, it is included in the presence of the additive.
The additive used in the production of the lactone compound is not particularly limited, but Bronsted acid is preferable, carboxylic acid and phenols are more preferable, and phenols are particularly preferable.

The phenols may have a substituent in addition to the phenolic hydroxyl group. The fact that it may have a substituent means that it may contain one or more of arbitrary bonds, functional groups, atoms, and the like. As substituents, for example, alkyl group, alkenyl group, alkynyl group, aryl group, alcoholic hydroxyl group, ester bond, siloxane bond, amide bond, sulfide bond, disulfide bond, ether bond, nitro group, cyano group, carbonyl group, sulfonyl Groups, halogens, silicon, phosphorus and the like can be mentioned. The position of the substituent is also not particularly limited.
Specifically, as phenols, monohydric phenols such as phenol, 2-methoxyphenol, 3-methoxyphenol, 4-methoxyphenol, orthocresol, metacresol, paracresol, 1-naphthol and 2-naphthol, and catechol. , Divalent phenols such as resorcinol and hydroquinone.

By carrying out the reaction in the presence of an additive, the production rate of the lactone compound is improved, and by-products (1,3-dioxacyclohepta-5-ene analog) derived from the cis diester compound are produced. It can be suppressed. Phenols to be used as additives can be appropriately selected depending on the cis-trans isomer ratio of the diester compound to be used and the purity required for the lactone compound, but from the viewpoint of the production rate of the lactone compound, phenol and hydroquinone can be selected. 1-naphthol and 2-naphthol are preferable from the viewpoint of suppressing by-products.
As these additives, commercially available ones can be used, and those obtained by manufacturing by a known method or the like can also be used. Further, these additives may be used alone or in combination of two or more.

(5) Conditions for Producing a Lactone Compound The amount of the orthocarboxylic acid ester used in the present invention is not particularly limited as long as the lactone compound can be efficiently obtained, but is 0.1 mol per 1 mol of the diester compound. It can be 20 mol or more, preferably 0.5 mol or more and 10 mol or less, more preferably 0.8 mol or more and 5 mol or less, further preferably 0.9 mol or more and 2 mol or less, and 1 mol or more and 1. 5 mol or less is particularly preferable. By setting the amount of the orthocarboxylic acid ester used to 0.1 mol or more and 20 mol or less with respect to 1 mol of the diester compound, the amount of the lactone compound produced per reaction volume can be increased.

The amount of the catalyst used in the present invention is not particularly limited as long as the lactone compound can be obtained efficiently and efficiently, but can be 0.000001 mol or more and 4 mol or less with respect to 1 mol of the diester compound. , 0.00001 mol or more and 1 mol or less is preferable, 0.00005 mol or more and 0.5 mol or less is more preferable, 0.0001 mol or more and 0.2 mol or less is further preferable, 0.0005 mol or more and 0.05 mol or less. Is particularly preferable, and 0.001 mol or more and 0.01 mol or less is most preferable. By setting the amount of the catalyst used to 0.000001 mol or more with respect to 1 mol of the diester compound, it is possible to effectively suppress the decrease in catalytic activity due to impurities. By setting the amount of the catalyst used to 4 mol or less with respect to 1 mol of the diester compound, the load on the post-treatment step after the reaction can be reduced and the economic efficiency can be improved.
Further, the catalyst may be in a state of being dissolved in the reaction solution or in a state of not being dissolved, but it is preferably in a state of being dissolved. When the catalyst is dissolved in the reaction solution, the production rate of the lactone compound can be improved.

When an additive is used in the present invention, the amount of the additive used is not particularly limited as long as the lactone compound can be obtained efficiently and efficiently, but 0.000001 mol with respect to 1 mol of the diester compound. It can be 4 mol or more, preferably 0.00001 mol or more and 1 mol or less, more preferably 0.00005 mol or more and 0.5 mol or less, further preferably 0.0001 mol or more and 0.2 mol or less, and 0. 0005 mol or more and 0.1 mol or less are particularly preferable, and 0.001 mol or more and 0.05 mol or less are most preferable. By setting the amount of the additive to be 0.000001 mol or more with respect to 1 mol of the diester compound, it is possible to effectively suppress the decrease in the effect of the additive due to impurities and efficiently obtain the lactone compound. By setting the amount of the additive used to 4 mol or less with respect to 1 mol of the diester compound, the load on the post-treatment step after the reaction can be reduced and the economic efficiency can be improved.
Further, the additive may be in a state of being dissolved in the reaction solution or in a state of not being dissolved, but it is preferably in a state of being dissolved. When the additive is dissolved in the reaction solution, the production rate and selectivity of the lactone compound can be improved.

When reacting the diester compound with the orthocarboxylic acid ester, a solvent may be used, but it is preferable not to use a solvent from the viewpoint of productivity. When a solvent is used, the type thereof is not particularly limited, but a large difference in boiling point from the lactone compound is preferable from the viewpoint of separation. Examples of the solvent include hydrocarbon solvents such as hexane, toluene, xylene and mesityrene, ether solvents such as diethyl ether and tetrahydrofuran, ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate and butyl acetate, and dimethylformamide. And amide-based solvents such as dimethylacetamide, sulfur-based solvents such as dimethylsulfoxide, alcohol-based solvents such as n-butanol and n-pentanol, and the like. These may be used alone or in combination of two or more. The amount of the solvent used is not limited and can be appropriately selected.

The reaction temperature is not particularly limited, but can be 60 ° C. or higher and 250 ° C. or lower, more preferably 100 ° C. or higher and 230 ° C. or lower, further preferably 120 ° C. or higher and 200 ° C. or lower, 140 ° C. or higher. It is particularly preferable that the temperature is ℃ or more and 180 ℃ or less. By setting the reaction temperature to 60 ° C. or higher, the reaction can proceed smoothly. By setting the reaction temperature to 250 ° C. or lower, coloring of the reaction solution and side reactions can be suppressed. The reaction temperature does not have to be constant and may be changed within a preferable range.

The reaction time is not particularly limited, and can be appropriately selected depending on the scale and conditions of the reaction. For example, the reaction time after adding the diester compound can be 0.5 hours or more and 80 hours or less, preferably 1 hour or more and 40 hours or less, and more preferably 3 hours or more and 20 hours or less. By setting the reaction time to 0.5 hours or more, the reaction can proceed smoothly. By setting the reaction time to 80 hours or less, coloring of the reaction solution and side reactions can be suppressed.

The pressure at the time of reaction is not particularly limited, and may be a reduced pressure state, an atmospheric pressure state, or a pressurized state.
The method of introducing the raw materials into the reaction vessel is not particularly limited, but all of them may be introduced at once, may be introduced in stages, may be introduced continuously, or these methods. The introduction method may be a combination of.
The reaction conditions in the method for producing the lactone compound are not particularly limited, and the reaction conditions can be appropriately changed in the reaction step.

The form of the reaction vessel for carrying out the reaction is not particularly limited, and a batch type tank type reactor, a continuous type tank type reactor, a continuous type tube type reactor and the like can be used.
The atmosphere during the reaction, purification of the product, storage of the solution containing the product and the purified lactone compound is not particularly limited. From the viewpoint of preventing ignition and coloring, an inert gas atmosphere may be used, and from the viewpoint of preventing polymerization of raw materials and products, an oxygen-containing gas atmosphere may be used.

The lactone compound obtained in the present invention can be purified as needed. The purification method is not particularly limited, and a known method can be used. Examples of the purification method include liquid separation, distillation, crystallization, filtration, chromatography and the like. These may be carried out individually or in combination of two or more kinds.
The distillation method is not particularly limited, and examples thereof include simple distillation, precision distillation, and thin film distillation. Distillation may be carried out under reduced pressure, atmospheric pressure, or pressurized pressure, but is preferably carried out under reduced pressure.

(6) Lactone compound, storage method and use thereof The lactone compound obtained in the present invention is a compound represented by the formula (2). R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ in formula (2) are synonymous with those in formula (1).

The storage container for the lactone compound obtained in the present invention is not particularly limited, and examples thereof include a glass container, a resin container, a metal storage tank, a drum can, and a lorry.
The lactone compound obtained in the present invention is not particularly limited, but may be used, for example, in food additives, cosmetic additives, pharmaceutical raw materials, fragrances, synthetic resin raw materials, resin additives, paints, various materials, and the like. it can.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples, and is arbitrarily modified and carried out without departing from the gist of the present invention. be able to.
In the examples, the analysis of the lactone compound and the like was performed by gas chromatography.
In the examples, 1,4-diacetoxy-2-butene (cis-trans mixture) has a purity of 97% by mass manufactured by Mitsubishi Chemical Corporation, and the isomer ratio is trans: cis = 87:13, and the formula ( ^{R 1} and R ² in 1) were methyl groups, and R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ were hydrogen. The trimethyl orthoacetate used was manufactured by Tokyo Chemical Industry Co., Ltd. and had a purity of 99% by mass. The 2-butene-1,4-diol (cis-trans mixture) used was manufactured by Tokyo Chemical Industry Co., Ltd. and had a purity of 98% by mass and an isomer ratio of trans: cis = 73:27. As cis-1,4-diacetoxy-2-butene, one manufactured by Tokyo Chemical Industry Co., Ltd. with a purity of 99% by mass was used. As the cis-butene-1,4-diol, one having a purity of 98% by mass manufactured by Tokyo Chemical Industry Co., Ltd. was used.

<Example 1>
In a 50 mL SUS autoclave, 3.00 g (16.9 mmol) of 1,4-diacetoxy-2-butene (cis-trans mixture), 3.14 g (26.1 mmol) of trimethyl orthoacetate, and 0.217 g of dibutyltin oxide as a catalyst. (0.871 mmol) and 0.148 g (0.871 mmol) of diphenyl ether as an internal standard substance were sequentially added, and the mixture was stirred at a bath temperature of 170 ° C. under pressure for 2 hours.
As a result, the amount of 3-vinyl-butyrolactone in the obtained reaction solution was 1.19 g (10.6 mmol), and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) was obtained. The rate was 63%.

これらの実施例から、種々のルイス酸触媒で、効率的に３−ビニル−ブチロラクトンが得られることがわかった。 <Examples 2 to 6 and Comparative Examples 1 to 4>
The same operation as in Example 1 was carried out except that 0.217 g (0.871 mmol) of dibutyltin oxide was used as the catalyst, and the catalyst species and the amount of catalyst (charged amount) shown in Table 1 were used. Table 1 also shows the amount of 3-vinyl-butyrolactone produced in the obtained reaction solution and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). In addition, "VBL" in the table indicates 3-vinyl-butyrolactone.

From these examples, it was found that 3-vinyl-butyrolactone can be efficiently obtained with various Lewis acid catalysts.

<Comparative example 5>
Instead of using 3.00 g (16.9 mmol) of 1,4-diacetoxy-2-butene (cis-trans mixture) as a raw material, 1.52 g (cis-trans mixture) of 2-butene-1,4-diol (cis-trans mixture) The same operation as in Comparative Example 1 was carried out except that 16.9 mmol) was used.
As a result, the amount of 3-vinyl-butyrolactone in the obtained reaction solution was 1.12 g (10.0 mmol), and the yield of 3-vinyl-butyrolactone with respect to 2-butene-1,4-diol (cis-trans mixture) was obtained. The rate was 59%.
From this comparative example, it was found that the reactivity of 1,4-diacetoxy-2-butene and 2-butene-1,4-diol was significantly different, and the present application could not be easily derived even with reference to the prior art.

これらの実施例から、１，４−ジアセトキシ−２−ブテン（シス−トランス混合物）に対して種々のモル比の触媒を用いても、３−ビニル−ブチロラクトンが効率的に得られることがわかった。 <Examples 7 to 9>
The same operation as in Example 1 was carried out except that the amount of dibutyltin oxide used as a catalyst was changed to the amount shown in Table 2. Table 2 also shows the amount of 3-vinyl-butyrolactone produced in the obtained reaction solution and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). In addition, "VBL" in the table indicates 3-vinyl-butyrolactone.

From these examples, it was found that 3-vinyl-butyrolactone can be efficiently obtained even when catalysts having various molar ratios to 1,4-diacetoxy-2-butene (cis-trans mixture) are used. ..

これらの実施例から、種々の反応温度において、３−ビニル−ブチロラクトンが効率的に得られることがわかった。 <Examples 10 to 15>
The same operation as in Example 8 was performed except that the bath temperature was changed from 170 ° C. to the temperature shown in Table 3. Table 3 also shows the amount of 3-vinyl-butyrolactone produced in the obtained reaction solution and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). In addition, "VBL" in the table indicates 3-vinyl-butyrolactone.

From these examples, it was found that 3-vinyl-butyrolactone can be efficiently obtained at various reaction temperatures.

<Example 16>
3.00 g (16.9 mmol) of 1,4-diacetoxy-2-butene (cis-trans mixture), 3.14 g (26.1 mmol) of trimethyl orthoacetate, 0.022 g of dibutyltin oxide as a catalyst in a 50 mL SUS autoclave. (0.087 mmol) and 0.148 g (0.871 mmol) of diphenyl ether as an internal standard substance were sequentially added, and the mixture was stirred at a bath temperature of 180 ° C. under pressure for 4 hours.
As a result, the amount of 3-vinyl-butyrolactone in the reaction solution 1 hour after the start of heating was 0.91 g (8.1 mmol), which was 3-vinyl- against 1,4-diacetoxy-2-butene (cis-trans mixture). The yield of butyrolactone was 48%.
The amount of 3-vinyl-butyrolactone in the reaction solution 4 hours after the start of heating was 1.63 g (14.5 mmol), and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) was obtained. The rate was 86%. The compound represented by the following formula (3) is 0.034 g (0.24 mmol), and the yield of the compound represented by the formula (3) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). Was 1.4%. The compound represented by the following formula (4) is 0.096 g (0.52 mmol), and the yield of the compound represented by the formula (4) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). Was 3.1%. The compound represented by the following formula (5) is 0.067 g (0.47 mmol), and the yield of the compound represented by the formula (5) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). Was 2.8%.

これらの実施例から、添加剤としてブレンステッド酸を加えると、３−ビニル−ブチロラクトンの生成速度が向上するだけでなく、式（５）で表される化合物の生成を抑制できることがわかった。 <Example 17>
The same operation as in Example 16 was carried out except that 0.096 g (0.871 mmol) of hydroquinone was added as an additive and the reaction was carried out.
As a result, the amount of 3-vinyl-butyrolactone in the reaction solution 1 hour after the start of heating was 1.60 g (14.3 mmol), which was 3-vinyl- against 1,4-diacetoxy-2-butene (cis-trans mixture). The yield of butyrolactone was 85%.
The amount of 3-vinyl-butyrolactone in the reaction solution 4 hours after the start of heating was 1.70 g (15.2 mmol), and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) was obtained. The rate was 90%. The compound represented by the formula (3) is 0.060 g (0.42 mmol), and the yield of the compound represented by the formula (3) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) is It was 2.5%. The compound represented by the formula (4) is 0.068 g (0.37 mmol), and the yield of the compound represented by the formula (4) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) is It was 2.2%. The compound represented by the formula (5) is 0.015 g (0.10 mmol), and the yield of the compound represented by the formula (5) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) is It was 0.6%.
Table 4 shows the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) and the formula (3) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). Yield of the compound to be obtained, yield of the compound represented by the formula (4) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture), 1,4-diacetoxy-2-butene (cis-trans mixture). ), The yield of the compound represented by the formula (5) is described. In addition, "VBL" in the table indicates 3-vinyl-butyrolactone.

From these examples, it was found that the addition of Bronsted acid as an additive not only improves the production rate of 3-vinyl-butyrolactone, but also suppresses the production of the compound represented by the formula (5).

<Example 18>
3.00 g (16.9 mmol) of 1,4-diacetoxy-2-butene (cis-trans mixture), 3.14 g (26.1 mmol) of trimethyl orthoacetate, 0.022 g of dibutyltin oxide as a catalyst in a 50 mL SUS autoclave. (0.087 mmol) and 0.148 g (0.871 mmol) of diphenyl ether as an internal standard substance were sequentially added, and the mixture was stirred at a bath temperature of 170 ° C. under pressure for 4 hours.
As a result, the amount of 3-vinyl-butyrolactone in the reaction solution 1 hour after the start of heating was 0.78 g (6.9 mmol), which was 3-vinyl- against 1,4-diacetoxy-2-butene (cis-trans mixture). The yield of butyrolactone was 41%.
The amount of 3-vinyl-butyrolactone in the reaction solution 4 hours after the start of heating was 1.44 g (12.8 mmol), and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) was obtained. The rate was 76%. The compound represented by the following formula (5) is 0.085 g (0.59 mmol), and the yield of the compound represented by the formula (5) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). Was 3.5%.

これらの実施例から、添加剤として種々のブレンステッド酸が、３−ビニル−ブチロラクトンの生成速度向上と、式（５）で表される化合物の抑制の効果があることがわかった。 <Examples 19 to 23>
The same operation as in Example 18 was carried out except that the additive species shown in Table 5 and the additive amount (charged amount) were further added and reacted. Yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture), compound represented by formula (5) with respect to 1,4-diacetoxy-2-butene (cis-trans mixture). The yields of the above are also shown in Table 5. In addition, "VBL" in the table indicates 3-vinyl-butyrolactone.

From these examples, it was found that various Bronsted acids as additives have the effect of improving the production rate of 3-vinyl-butyrolactone and suppressing the compound represented by the formula (5).

<Example 24>
In a 50 mL SUS autoclave, 3.00 g (17.2 mmol) of cis-1,4-diacetoxy-2-butene, 3.14 g (26.1 mmol) of trimethyl orthoacetate, and 0.217 g (0.871 mmol) of dibutyltin oxide as a catalyst. ), 0.096 g (0.871 mmol) of hydroquinone as an additive, and 0.148 g (0.871 mmol) of diphenyl ether as an internal standard substance were sequentially added, and the mixture was stirred at a bath temperature of 170 ° C. under pressure for 4 hours.
As a result, the amount of 3-vinyl-butyrolactone in the obtained reaction solution was 1.19 g (10.6 mmol), and the yield of 3-vinyl-butyrolactone with respect to cis-1,4-diacetoxy-2-butene was 62%. Met.
From this example, it was found that a lactone compound can be efficiently obtained even when a cis diester compound is used.

<Comparative example 5>
Instead of using 3.00 g (17.2 mmol) of cis-1,4-diacetoxy-2-butene as a raw material, 1.55 g (17.2 mmol) of cis-2-butene-1,4-diol was used. Performed the same operation as in Example 24.
As a result, the amount of 3-vinyl-butyrolactone in the obtained reaction solution was 0.62 g (5.5 mmol), and the yield of 3-vinyl-butyrolactone with respect to cis-2-butene-1,4-diol was 32%. Met.
From this comparative example, it was found that the use of a diester compound as a raw material has a remarkable effect when producing a lactone compound using an easily available cis compound.

<Example 25>
10.0 g (56.3 mmol) of 1,4-diacetoxy-2-butene (cis-trans mixture), 10.5 g (87.1 mmol) of trimethyl orthoacetate, in a 50 mL glass three-necked flask equipped with a manual reflux tube. 0.072 g (0.29 mmol) of dibutyltin oxide was added as a catalyst, 0.320 g (2.90 mmol) of hydroquinone was added as an additive, and 0.494 g (2.90 mmol) of diphenyl ether was sequentially added as an internal standard substance. The mixture was stirred at 106 to 137 ° C. under normal pressure for 7 hours. During that time, the light boiling point component was distilled off while switching to total reflux when the column top temperature was 80 ° C. or higher and total distillation when the column top temperature was less than 80 ° C.
As a result, the amount of 3-vinyl-butyrolactone in the obtained reaction solution was 5.26 g (46.9 mmol), and the yield of 3-vinyl-butyrolactone with respect to 1,4-diacetoxy-2-butene (cis-trans mixture) was obtained. The rate was 83%.
From this example, it was found that 3-vinyl-butyrolactone can be efficiently obtained even under normal pressure.

Although the present invention has been described above with reference to the embodiments and examples, the present invention is not limited to the above embodiments and examples. Various changes that can be understood by those skilled in the art can be made within the scope of the present invention in terms of the structure and details of the present invention.

Claims (8)

The diester compound represented by the following formula (1) is reacted with one or more selected from trimethyl orthoacetate, triethyl orthoacetate and tri-n-butyl orthoacetate in the presence of a Lewis acid catalyst, and the following formula (2) ) Is a method for producing a lactone compound.

(In the formula, R ¹ and R ² represent hydrocarbon groups having 1 to 20 carbon atoms, and R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ have hydrogen or a substituent. It represents a good hydrocarbon group having 1 to 20 carbon atoms, and these hydrocarbon groups may have an unsaturated bond or an ether bond.)

(In the formula, R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ represent hydrogen or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent and have an unsaturated bond. It may have an ether bond.) The method for producing a lactone compound according to claim 1, wherein the Lewis acid is a metal compound. The method for producing a lactone compound according to claim 1 or 2, wherein the ligand of the Lewis acid is an alkyl group, an alkoxy group, a carboxy group or acetylacetone. The method for producing a lactone compound according to any one of claims 1 to 3, wherein the Lewis acid is dialkyltin oxide. The method for producing a lactone compound according to any one of claims 1 to 4, wherein R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ^{8 of the diester compound are hydrogen.} The method for producing a lactone compound according to any one of claims 1 to 5, ^{wherein R 1} and R ² of the diester compound are methyl groups. The method for producing a lactone compound according to any one of claims 1 to 6 , wherein a Bronsted acid is further coexisted as an additive in addition to the Lewis acid. The method for producing a lactone compound according to claim 7 , wherein the Bronsted acid is a phenol.