JPH0733756A - Production of lactones - Google Patents

Abstract

PURPOSE:To provide a method for producing lactones from a saturated or an unsaturated dicarboxylic acid anhydride in high yield under mild conditions. CONSTITUTION:Maleic anhydride is hydrogenated in a liquid-phase homogeneous system to produce gamma-butyrolactone. In the process, a tertiary alcohol is added to carry out the reaction in the presence of a ruthenium compound and a bis(diarylphosphino)ferrocene.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing lactones, and more particularly to a method for producing γ-butyrolactone which is a compound useful as a raw material for synthesis of solvents, pyrrolidones and the like.

[0002]

2. Description of the Related Art Hitherto, many proposals have been made regarding a method for producing a lactone by hydrogenating an anhydride of a saturated and / or unsaturated dicarboxylic acid in a liquid phase homogeneous system.

For example, US Pat. No. 3,957,827 describes a method for hydrogenating succinic anhydride using RuCl ₂ (PPh ₃ ) ₃ as a catalyst. In U.S. Pat. No. 4,485,246, RuCl ₂ (PPh ₃ ) ₃ is used as a catalyst, and an organic amine compound is allowed to coexist with it.
Techniques for reducing reaction time are described. Further, Japanese Patent Application Laid-Open No. 64-25771 describes a method of allowing an organic acid to coexist in Ru (acac) ₃ and trioctylphosphine in a hydrogenation reaction of succinic anhydride.

[0004]

It is known that when a ruthenium compound is used as a catalyst in a liquid phase homogeneous system, the reaction proceeds under relatively mild conditions, but the ruthenium compound has a low catalytic activity. There is a drawback that the reaction takes a long time. In the method of coexisting an organic amine compound described in US Pat. No. 4,485,246, RuCl ₂ (P
Hydrochloric acid generated from Ph ₃ ) ₃ and an organic amine compound form a hydrochloride, which makes it impossible to carry out the reaction in a homogeneous system. In addition, Ru (ac
It is described that the method of allowing an organic acid to coexist in ac) ₃ and trioctylphosphine significantly reduces the yield when maleic anhydride is used as a raw material.

The object of the present invention is to produce lactones, particularly γ-butyrolactone, with high activity and high yield under relatively mild conditions when hydrogenating a saturated and / or unsaturated dicarboxylic acid anhydride as a raw material. To provide a method.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that hydrogenation by adding a tertiary alcohol in the presence of a ruthenium compound and an organic phosphine compound. The inventors have found that the activity is improved and have completed the present invention.

That is, the present invention is to hydrogenate an anhydride of a saturated and / or unsaturated dicarboxylic acid in a liquid phase homogeneous system in the presence of a ruthenium compound and an organic phosphine compound.
The present invention relates to a method for producing lactones, which comprises adding a tertiary alcohol and hydrogenating. The present invention will be described in detail below.

In the present invention, an anhydride of saturated and / or unsaturated dicarboxylic acid is used as a raw material. Saturation and /
The type of the unsaturated dicarboxylic acid anhydride is not particularly limited, but a dicarboxylic acid anhydride having 4 to 10 carbon atoms can be preferably used. Specific examples include maleic anhydride, succinic anhydride, itaconic anhydride, citraconic anhydride, methylsuccinic anhydride, glutaric anhydride and the like. Of these, maleic anhydride and succinic anhydride are more preferably used. Further, the saturated or unsaturated dicarboxylic acid anhydride as a raw material may be mixed in any ratio as long as the hydrogenation products are the same.

In the present invention, a ruthenium compound is used as a catalyst. The ruthenium compound is not particularly limited, but various ruthenium inorganic compounds, organic compounds or complex compounds can be used. Specifically, inorganic acid salts such as ruthenium chloride, ruthenium bromide, ruthenium iodide, ruthenium nitrate, organic acid salts such as ruthenium acetate, chelate compounds such as tris (acetylacetone) ruthenium,
Organics such as dichlorotris (triphenylphosphine) ruthenium, chlorotris (triphenylphosphine) hydridoruthenium, dichlorotetrakis (triphenylphosphine) ruthenium, dichlorodicarbonylbis (triphenylphosphine) ruthenium, tricarbonylbis (triphenylphosphine) ruthenium Examples include phosphine complex compounds.

Further, chlorohydridocarbonyl tris (triphenylphosphine) ruthenium, bis (tri-
n-butylphosphine) tricarbonyl ruthenium and other organic phosphine complex compounds, dipotassium tetracarbonyl ruthenate, pentacarbonyl ruthenium, dibromotricarbonyl ruthenium, dodecacarbonyl triruthenium, tetrahydrido decacarbonyl ruthenium,
Examples thereof include carbonyl complex compounds such as tetracarbonyldihydridoruthenium, octadecacarbonylhexaruthenate dicesium, and undecacarbonylhydridotriruthenate tetraphenylphosphonium. The amount of the ruthenium compound used is 0.00001 to 100 mol, preferably 0.001 to 10 mol, as ruthenium in 1 liter of the reaction solution.

In the present invention, an organic phosphine compound is used together with the ruthenium compound. Some ruthenium compounds coordinate with an organic phosphine compound to form a ruthenium complex and others exchange ligands, but there is no problem. For example, a desired ruthenium organic phosphine complex may be synthesized and used in the reaction solution, if necessary, or a ruthenium compound and an organic phosphine compound may be previously reacted by a known method to synthesize a ruthenium organic phosphine complex. You can use it as well. Of course, it goes without saying that the ruthenium compound and the organic phosphine compound may simply coexist in the reaction system.

The organic phosphine compound used in the present invention is not particularly limited as long as phosphine is contained in the molecule, and various aliphatic or aromatic organic phosphine compounds can be used. Specifically, as an organic monophosphine having one phosphine in the molecule, tri (n-
Butylphosphine), tri (t-butylphosphine),
Trialkylphosphines such as tri (n-octylphosphine) and tricyclohexylphosphine, triarylphosphines such as triphenylphosphine, tritolylphosphine and tri (methoxytolyl) phosphine, dimethylphenylphosphine, diethylphenylphosphine, ethyldiphenylphosphine And other alkylarylphosphines.

As the organic diphosphine having two phosphines in the molecule, bisdiarylphosphino such as 1,1'-bis (diphenylphosphino) ferrocene and 1,1'-bis (ditolylphosphino) ferrocene. Ferrocenes can be mentioned. Preferred is 1,1'-bis (diphenylphosphino) ferrocene. These organic phosphine compounds can be used alone or in combination of two or more.

The amount of the organic phosphine compound used in the present invention is 0.1 to 100 mol, preferably 0.5 to 50 mol, based on 1 mol of the ruthenium catalyst. If it is less than 0.1 mol, a sufficient addition effect is not exhibited, and if it exceeds 100 mol, the activity may be significantly reduced.

Further, in the present invention, the reaction is carried out by adding a tertiary alcohol to the reaction system. As a tertiary alcohol,
For example, tertiary butyl alcohol, tertiary amyl alcohol, 2-ethyl-2-butanol, triethylcarbinol, 1,1-dimethylbenzyl alcohol, 1-methyl-1-phenylbenzyl alcohol, dimethylphenylcarbinol, diphenylmethylcarbinol. , Triphenylcarbinol, 3-ethyl-5,
5-dimethyl 3-hexanol etc. are mentioned. Preferably, tertiary butyl alcohol, tertiary amyl alcohol, 1,1-dimethylbenzyl alcohol, 1-methyl-1-phenylbenzyl alcohol, triethylcarbinol, triphenylcarbinol, 3
-Ethyl-5,5-dimethyl-3-hexanol.

The amount of tertiary alcohol used is saturated and / or
Alternatively, it is used in an amount of 0.05 to 100 mol, preferably 0.1 to 50 mol, based on the anhydride of unsaturated dicarboxylic acid.

The solvent used in the present invention is not particularly limited as long as it does not react with the substrate, is inactive in the hydrogenation reaction, and does not react with the product lactone.
For example, ethers such as diethyl ether, dimethoxyethane, diglyme, triglyme, tetraglyme, tetrahydrofuran and dioxane, aliphatic hydrocarbons such as n-hexane and cyclohexane, aromatic hydrocarbons such as benzene, toluene, ethylbenzene, cumene and diisopropylbenzene. , Lactones such as γ-butyrolactone, 2
-Pyrrolidone, N-methylpyrrolidone and other amides,
Examples thereof include ureas such as N, N, N ', N'-tetramethylurea and N, N'-dimethylimidazolidione. The amount of this solvent used is not particularly limited as long as the raw materials are dissolved at the reaction temperature.

The reaction according to the method of the present invention is carried out under heating and hydrogen pressure. The reaction method is not particularly limited, and may be a flow system, a batch system or a semi-batch system.

The reaction temperature is usually 50 to 250 ° C, preferably 120 to 230 ° C. If the temperature is higher than this, side reaction products tend to increase, and conversely, if the temperature is lower than this, there is a disadvantage in the reaction rate. The pressure of hydrogen is usually 10 to 200 kg / cm ² G, preferably 1
5-120 kg / cm ² G is selected. At a higher pressure than this, it is unnecessary in terms of equipment and economically, and at a lower pressure than this, the reaction rate becomes slow, which is disadvantageous.

The reaction time varies depending on the setting method of temperature, pressure, amount of catalyst and the like or the reaction method, so that it is difficult to determine the range unconditionally, but in the batch system and the semi-batch system, it is usually 1 to 30 hours. , Preferably 1 to 10 hours. The reaction time may be longer than 30 hours, but the reaction proceeds sufficiently within this range. On the other hand, if it is less than 1 hour, a high conversion rate may not be obtained. Further, in the continuous reaction, the residence time may be 0.1 to 10 hours.

[0021]

[Examples] Hereinafter, the present reaction will be described in more detail with reference to Examples, but the present reaction is not limited to these Examples.

Example 1 0.98 g (10 mmol) of maleic anhydride and 29 mg of dichlorotris (triphenylphosphine) ruthenium were added to a 100 ml stainless steel autoclave.
03 mmol), 1,1'-bis (diphenylphosphino) ferrocene 33 mg (0.06 mmol), tertiary butyl alcohol 0.92 g (12.4 mmo)
l) and 10 g of tetraglyme were charged, the system was sufficiently replaced with hydrogen, and then hydrogen was injected under pressure to 50 kg / cm ² G. The temperature was raised to 200 ° C. with heating and stirring, and a hydrogenation reaction was performed for 2 hours.

After completion of the reaction, the autoclave was cooled to room temperature, and subsequently, hydrogen was purged and the reaction liquid was taken out. As a result of analyzing the reaction liquid by gas chromatography, γ-
The yield of butyrolactone was 71.8 mol% based on the maleic anhydride as a raw material.

Comparative Example 1 The reaction was performed in the same manner as in Example 1 except that tertiary butyl alcohol was not used. As a result of analyzing the reaction solution, the yield of γ-butyrolactone was 49.3 mol% with respect to the maleic anhydride as a raw material.

Examples 2 to 6 Reactions and analyzes were carried out in the same manner as in Example 1 except that various alcohols were used instead of tertiary butyl alcohol. The results are shown in Table 1.

[0026]

[Table 1]

Examples 7 to 9 The reaction was carried out in the same manner as in Example 1 except that tertiary amyl alcohol was used instead of tertiary butyl alcohol and the amount used was changed. The results are shown in Table 2.

[0028]

[Table 2]

Example 10 1.0 g of succinic anhydride was used in place of maleic anhydride (1
0 mmol) was used and the reaction was carried out in the same manner as in Example 2 except that the reaction temperature was 180 ° C. As a result of analyzing the reaction liquid, the yield of γ-butyrolactone was 71.7 mol% based on the raw material succinic anhydride.

Comparative Examples 2 to 6 Tertiary butyl alcohol was added to other alcohols (10
The reaction was performed in the same manner as in Example 1 except that the amount was changed to mmol). The results are shown in Table 3.

[0031]

[Table 3]

[0032]

According to the present invention, when hydrogenating a saturated and / or unsaturated dicarboxylic acid anhydride as a raw material in a liquid phase homogeneous system, a tertiary alcohol is added to the reaction system in the presence of a ruthenium compound and an organic phosphine compound. The lactones can be produced with high activity and high yield by adding.

[0033]

Claims (3)

[Claims] 1. When hydrogenating an anhydride of a saturated and / or unsaturated dicarboxylic acid in a liquid phase homogeneous system in the presence of a ruthenium compound and an organic phosphine compound, a tertiary alcohol is used.
The method for producing lactones is characterized in that the lactone is added and hydrogenated. 2. The saturated and / or unsaturated dicarboxylic acid anhydride is an anhydride of succinic acid and / or maleic acid,
The method for producing a lactone according to claim 1, wherein the lactone is γ-butyrolactone. 3. The method for producing a lactone according to claim 1, wherein the organic phosphine compound is bis (diarylphosphino) ferrocene.