JPS63150245A - Production of carboxylic acid ester - Google Patents

Abstract

PURPOSE:To simplify post-treatment steps, e.g. distillation step of the product, etc., efficiently, industrially and advantageously obtain the titled novel compound in high yield without forming water, by reacting a carboxylic acid anhydride with an ether in the presence of an acid catalyst. CONSTITUTION:A carboxylic acid anhydride, e.g. acetic anhydride, etc. expressed by formula I (R<1> and R<2> are H or monofunctional hydrocarbon group) or phthalic anhydride, etc., expressed by formula II (R<3> is bifunctional hydrocarbon group, etc.) is reacted with an ether expressed by formula III (R<4> and R<5> are monofunctional hydrocarbon group), e.g. ethyl ether, etc., or formula IV (R<6>-R<11> are H or hydrocarbon group), e.g. dimethyl ether, etc., if necessary, in a solvent in the presence of an acid catalyst normally at 30-350 deg. under ordinary pressure - 50atmG pressure to afford the aimed compound, e.g. compound expressed by formula V, IV, etc. BF3.O(Et)2, FeCl2, SnCl4, heteropoly acids, sulfuric acid, zirconium phosphate, etc., are used as the acid catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a carboxylic acid ester.

[Prior art and its problems] Carboxylic acid esters are usually produced by esterification (dehydration condensation) of a corresponding carboxylic acid and an alcohol. During esterification, a large amount of water is usually produced as a by-product. Since the by-produced water forms an azeotrope with the unreacted alcohol and the product ester, it has drawbacks such as difficulty in isolating the product.

[Objective of the Invention J The object of the present invention is to solve the above-mentioned problems and to produce a carboxylic acid ester which is extremely advantageous industrially by a completely new reaction that does not produce water and only produces a carboxylic ester. The purpose is to provide a manufacturing method.

[Means for Achieving the Object 1 Based on the above circumstances, the present inventors have conducted intensive research into a new and industrially advantageous method for producing carboxylic acid esters, and have surprisingly discovered that carboxylic acid anhydride They discovered a novel and efficient reaction in which only carboxylic acid esters are produced when a compound and an ether are reacted in the presence of a specific catalyst, and based on this knowledge, they completed the present invention.

That is, the present invention is a method for producing a carboxylic acid ester, which is characterized by reacting a carboxylic acid anhydride and an ether in the presence of an acid catalyst.

The method of this invention will be explained in detail below.

As the carboxylic anhydride, which is one of the reaction raw materials in the method of this invention, various carboxylic anhydrides such as chain carboxylic anhydride and cyclic carboxylic anhydride can be used, but the following are usually used. General formula (Equation [1], Equation [2])
A carboxylic acid anhydride represented by can be suitably used.

Here, in the above formula, 1lil and R2 are each,
Represents a hydrogen atom or a monovalent hydrocarbon group.

Examples of this hydrocarbon group include a saturated or unsaturated chain hydrocarbon group, a cyclic hydrocarbon group, an aromatic hydrocarbon group, and more specifically, a carbon number of 1 to 12 (hereinafter referred to as 01-C12) alkyl group, C3-
C20 preferably 05 to C10 cycloalkyl group, 0
Examples include a 2-C20 alkenyl group, a C2-C20 alkynyl group, a C6-cte, preferably 08-C12 aryl group, and a C7-C17, preferably 07-C13 aralkyl group.

However, R1 and R2 are not necessarily limited to the above-mentioned groups, and as long as they do not interfere with the reaction of the method of this invention, for example, halogen atoms, oxygen atoms,
Even if it is a monovalent substituted hydrocarbon group having a substituent containing a heteroatom such as a nitrogen atom, a phosphorus atom, a sulfur atom, or a silicon atom, or a monovalent substituted hydrocarbon group containing the above heteroatom. good.

Note that R1 and R2 may be the same group or different groups.

Here, in the above formula, R3 represents a divalent hydrocarbon group or the like.

Examples of the hydrocarbon group include saturated and unsaturated chain hydrocarbon groups, cyclic hydrocarbon groups, and aromatic hydrocarbon groups.

More specifically, this hydrocarbon group includes, for example, 0
2-CI2 fullkylene group, C3-C20, preferably C5-CIO cycloalkylene group, C2-C20 alkynylene, C2-C2G alkynylene group, 06-
C1B, preferably 06-C12 arylene group such as phenylene, C7-C17, preferably 07-C13
Examples include an aralkylene group, or a divalent hydrocarbon group in which one side is an alkyl group and the other side is an aryl group.

However, R3 is not necessarily limited to the above-mentioned groups, and as long as it does not interfere with the reaction of the method of this invention, for example, a halogen atom, an oxygen atom, a nitrogen atom, a phosphorus atom, a sulfur atom, It may be a divalent substituted hydrocarbon group having a substituent containing a heteroatom such as a silicon atom, or a divalent substituted 'saponified hydrogen group containing the above-mentioned heteroatom.

Specific examples of the carboxylic acid anhydride represented by the formula [11] are shown for the purpose of mere illustration: formic acid anhydride, acetic anhydride, propionic anhydride, acetic acid anhydride, isoacetic anhydride, valeric acid Anhydride, isovaleric anhydride, 2-methylacetic anhydride, pivalic anhydride, hexanoic anhydride, heptanoic anhydride, octanoic anhydride, decanoic anhydride, undecanoic anhydride, dodecanoic anhydride , tetradecanoic anhydride, hexadecanoic anhydride, octadecanoic anhydride,
Saturated chain carboxylic acid anhydrides such as acetic propionic anhydride, acetic butanoic anhydride, diacrylic anhydride, methacrylic anhydride, l.

2-butenoic anhydride, 3-butenoic anhydride, pentenoic anhydride, hexenoic anhydride, octenoic anhydride, decenoic anhydride, undecenoic anhydride, dodecenoic anhydride, tetradecenoic anhydride, hexadecene Acid anhydride, octadecenoic anhydride, 2-butic acid anhydride, 3- to xydic acid anhydride, octadecic acid anhydride, acetic acid acrylic anhydride,
Unsaturated chain carboxylic anhydrides such as acetic butenoic anhydride, acetic hexic anhydride, etc. Schiff is pentanecarboxylic anhydride, cyclohexanecarboxylic anhydride, methylcyclohexanecarboxylic anhydride, cyclohexylmethanecarboxylic anhydride Anhydrides of saturated or unsaturated cyclic carboxylic acids such as cyclohexanecarboxylic anhydride, cyclooctanecarboxylic anhydride, cyclohexanecarboxylic anhydride, acetic acid cyclohexane anhydride: benzoic anhydride, orthomethylbenzoic acid Anhydride, metamethylbenzoic anhydride, paramethylbenzoic anhydride, dimethylbenzoic anhydride, trimethylbenzoic anhydride, tetramethylbenzoic anhydride, pentamethylbenzoic anhydride, ethylbenzoic anhydride, propylbenzoic anhydride Butylbenzoic anhydride, hexylbenzoic anhydride, dodecylbenzoic anhydride, vinylbenzoic anhydride, propenylbenzoic anhydride, phenylbenzoic anhydride, cyclohexylbenzoic anhydride, phenylmethanecarboxylic anhydride , 1-phenylethanecarboxylic anhydride, 2-phenylethanecarboxylic anhydride, naphthalenecarboxylic anhydride, methylnaphthalenecarboxylic anhydride, acetic benzoic anhydride, acetic methylbenzoic anhydride, terephthalic diacetic anhydride Aromatic carboxylic acid anhydrides such as chloroacetic anhydride, fluoroacetic anhydride, chlorobenzoic anhydride, acetylbenzoic anhydride, and other substituted carboxylic acid anhydrides.

Among these, alkanoic acid anhydrides such as acetic anhydride and propionic anhydride; aromatic carboxylic acid anhydrides such as benzoic anhydride and methylbenzoic anhydride can be preferably used.

Specific examples of the cyclic carboxylic acid anhydride represented by the formula [21] are shown merely for the purpose of illustration and not limitation: For example, succinic anhydride, maleic anhydride, methyl phthalic anhydride, ethyl phthalic anhydride, dimethyl Phthalic anhydride, methyl-2-butene dianhydride, ethyl phthalic anhydride, pentanedic anhydride, methyl phthalic anhydride, ethyl phthalic anhydride, hexane dianhydride, phthalic anhydride, methyl phthalic anhydride, dimethyl phthalic anhydride Examples include acid anhydride, ethyl phthalic anhydride, and 1,2,4.5-benzenetetracarboxylic anhydride.

Among these, maleic anhydride, phthalic anhydride, succinic anhydride, etc. can be preferably used.

Note that these carboxylic acid anhydrides may be used alone or in combination of two or more.

The ether, which is another reaction raw material in the method of the present invention, is not particularly limited as long as it is an ether composed of an ether bond and a hydrocarbon acid. For example, the ether has the following general formula (
Examples include chain ethers and cyclic ethers such as the ethers represented by formulas [31 and 4].

R4-0-R5[3] Here, 1li4 and 1li5 each represent a monovalent hydrocarbon group. As this hydrocarbon group, the above-mentioned [1]
Of the formulas 1(I and 1li2), those corresponding to hydrocarbons can be mentioned. Note that R4 and R5 may be different groups or may be the same group.

Here, 1li6, R7, R8, R9, RIG and R11 each represent a hydrogen atom or a hydrocarbon group, and more specifically, among R1 and R2 in the formula [11],
Represents a group corresponding to a hydrogen source or a hydrocarbon group.

Note that R6 to R11 may be the same group or different groups. Further, n represents an integer of θ to 10, preferably an integer of 1 to 8.

In addition to the ether represented by the above general formula, examples of the ether include cyclic ethers such as benzofuran, dioxane, and trioxane, 1.2-'dimethoxyethane, 1.2-dimethoxyethane, and 1.3-dimethoxyethane. Examples include chain polyethers such as propane, 1,4-dimethoxybutane, and 0-ethylpolyoxyethylene, and hydrocarbon group-substituted derivatives thereof.

Specific examples of the ethers are given by way of illustration and not limitation, such as dimethyl ether, diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, diallyl ether, diallyl ether, dioctyl ether, dicyclohexyl ether, diphenyl ether, bis( 4-methyl phenyl) ether, dibenzyl ether, divinyl ether, diallyl ether, ethyl methyl ether, methyl phenyl ether, ethyl phenyl ether, ethyl vinyl ether, ethyl propyl ether, methyl propyl ether,
1,2-jethoxyethane, 1゜2-dimethoxyethane, 1,2-dumexy-1-methylethane, 1,3-dimethoxypropane, 1,4-jethoxyethane, 0-ethylpolyoxyethylene, 0-phenylpolyoxyphenylene, Chain ethers such as dimethoxybenzene and jetoxybenzene; ethylene oxide, propylene oxide,
1,2-epoxybutane, 2-butene epoxide, 2,
3-epoxybutane, styrene oxide 1.1,3-epoxypropane, 1,3-epoxybutane, tetrahydrofuran, methyloxolane, dimethyloxolane, ethyloxolane, propyloxolane, 2,5-dihydrofuran, furan, 1,3-dioxolane, 1,5-epoxypentane, 1,4-dioxane, 1,3-dioxane, 4,4-dimethyl-1,3-dioxane, 1,3
．． 5-trioxane, methyl-1,5-epoxypentane, l.

6-nipoxyhexane, 1,7-epoxyhebutane, 1
Examples include cyclic ethers such as 4-epoxycyclohexane.

Among these, dimethyl ether, diethyl ether,
Tetrahydrofuran and the like can be particularly preferably used.

Note that these ethers may be used alone or in combination of two or more.

The acid catalyst used as a catalyst in the method of the present invention includes a protic acid, an aprotic acid, an acid substance that is both a protic acid and an aprotic acid, or an acid substance containing these, and when used, a protic acid and/or Examples include acid substance precursors that can function as aprotic acids.

These acids and acid substances containing acids include organic acids, inorganic acids,
It may be any acid substance or acid substance precursor that is both an organic acid and an inorganic acid, or an acid substance or acid substance precursor containing one or more of these, and The state in which it is used or the state in which it is used may be a solid state, a gaseous state, a liquid state, a solution state, a dispersion state, or any combination thereof.

Among these various acids, acid substances or acid substance precursors, those suitable for use in the process of the present invention are presented by way of example only, and not by way of limitation, in the customary groupings.

(Group a) Periodic table Ia, Ib, IIa, Ilb, ma, I[Ib,
IVa, IVb, Va, Vb, VIa
, ■ b and ■ group metal elements or metalloid elements, halides such as phosphorus, sulfur, oxyhalides, or two or more types selected from these metal elements, metalloid elements, phosphorus, sulfur, etc. So-called Lewis acids in the narrow sense, such as complex halides and complex oxyhalides containing the elements; (Here, halogen is one or more selected from fluorine, chlorine, bromine, and iodine. ): (Group b) Non-oxygen protonic acids such as hydrohalic acid such as hydrogen dihydride, hydrogen chloride, hydrogen bromide, and hydrogen iodide: Inorganic oxygen such as sulfuric acid and phosphoric acid Acidic protonic acids; Protonic acids such as sulfonic protonic acids such as chlorosulfonic acid, fluorosulfonic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, trifluoromethanesulfonic acid; (Group 0) Crystalline aluminosilicate or aluminosilicate such as zeolite and mordenite, acidic clay minerals such as bentonite, montmorillonite, and activated clay; silica alumina,
Acidic composite oxides such as alumina boria, syria titania, isopoly acid, and heteropolyacid; strongly acidic solid oxides such as phosphorus pentoxide, sulfur trioxide, niobium oxide, and tungsten acid;
Acidic metal phosphates such as zirconium phosphate, crystalline zirconium phosphate, and anhydrous aluminum phosphate; Acidic sulfates or acidic oxysulfates such as aluminum sulfate, titanium sulfate, and zirconyl sulfate; Strongly acidic cation exchange resins ;
Examples include solid acids such as sulfuric acid, phosphoric acid, etc., supported or attached to a carrier such as silica, alumina, diatomite, and activated carbon;

Specific examples of the above (group a) include, for example, NaX,
LiX, BeXz, MgX2. BI3, B2 I4, AJLh, Ga
X3, InX, InX2, InX3, TiX
, TiX3, TiX4.5iXn, 5i2es
, 5i3Xs, 5ipX+a, 5i5X+2, GeX
, GeX2, GeX4.5nX2.5nX4. P
X3, PXs, P2X4, AsX3, AsX5
, 5bx3 , 5bXs , BiX, B
1X2, Bih, TiX2, TiX
3, TiXa, ZrX2, ZrX3
, ZrXa, VX2, VX3,
WXa, CrX2, CrX3, M
oX2, MOX3, MOX4, MO
X5, WX2. Wh, WX4. W
Xs, WXa, MnX2, N! Ix
3, NllX4, ReX3, R[!
X4, ReX5, FeX2, FeX3
, COx2, CoX:+, GoXn
, NiX2, RuX, RuX2
, RIIX3 , RuX1+ , RuX:+
, Ir13, PtX2, PtX4
, PdXz, 08X3, GuX, C
uX2, AuX, AuX2, ZnXz
, CdX2. Hg2X 2, HgX2
, 5nOX2, POX3, GrOXn
, MOOX4, NaI4. Re0X3(ko;-
TE and X represent one or more selected from F, C1, Br, and I. ), etc.

In addition, these Lewis acids, protonic acids, solid acids, etc. can be used as ether complexes, amine complexes, ammine complexes, phosphine complexes, nitrile complexes, carbonyl complexes, and olefin complexes, as long as they can function as acid catalysts during the above reaction. , as various complexes such as aqua complexes, or as ammonium complexes, phosphonium salts, salts such as onium salts such as oxonium salts, solutions of water, alcohols, ketones, nitriles, halogenated hydrocarbons, esters, ethers, etc. It is also possible to use it as

Furthermore, these acids, acid substances, or acid substance precursors may be used as necessary before being used in the reaction.

It can be used after being subjected to activation treatments such as heat treatment and dehydration treatment. Among these, solid oxide-based solid acid catalysts are usually desirably activated by this heat dehydration treatment before being used in the reaction. .

The solid acid catalyst such as the solid acid mentioned above is not particularly limited in its shape, and may be piece-shaped (spherical),
Used in various shapes such as pellets, rods, strips, plates, granules, powder, fine powder, ultrafine particles, fibers, hollow systems, tubes, cylinders, crosses, and monoliths. It can be used in fixed layer method, distribution layer method,
It can be used in various ways, such as in a moving bed or in a suspended state.

Among these various acid catalysts, those which can be particularly preferably used are shown merely for the purpose of illustration and not limitation, such as boron trifluoride, ether complex, ferric chloride, tin tetrachloride, and 12-molybdoline. Acids, heteropolyacids such as I2-molybdosilicic acid, 12-tungstophosphoric acid, and 12-tungstosilicic acid, sulfuric acid, crystalline zirconium phosphate, and the like.

Note that these acid catalysts may be used alone or in combination of two or more. Furthermore, various co-catalysts, additives, etc. may be added to these catalysts, if necessary, for the purpose of improving activity, improving selectivity, improving catalyst life, etc.

In the method of the present invention, one or two of the carboxylic acid anhydrides and the ether are reacted in the presence of the acid catalyst.
Generates more than one type of carboxylic acid ester.

The types of carboxylic acid esters produced, the number of these types, and if two or more types of carboxylic esters are produced, their proportions, etc. will depend on the carboxylic acid anhydride used, the type of ether, the usage ratio, and other conditions. different.

An example of the general formula of the produced carboxylic ester is shown below, not by way of limitation, but merely for the purpose of illustrating the correspondence with the reaction raw materials used.

That is, for example, when the carboxylic acid anhydride represented by the above [month] and the ether represented by the above [31 formula] react without side reactions, RI GOOR4, RIGOOR5, R2GOOR4,
It is possible to produce a carboxylic acid ester represented by the general formula R2GOOR5. Here, when R1 and R2 are the same group, and R4 and R5 are the same group, 1
Two types of carboxylic esters are generated, and when the groups of either one of R1 and R2 or R4 and R5 are different from each other, two types of carboxylic esters are generated, and further,
R1,! -12, when R4 and R5 are different, four types of carboxylic acid esters can be produced.

The carboxylic acid anhydride represented by the formula [21] and the carboxylic acid anhydride represented by the formula [21]
When the ether represented by formula 31 reacts without side reactions, R4-0CO-R3-GOOR5, R40CO-R3-
It is possible to produce a carboxylic acid ester represented by GOOR4, R50GO-R3-GOOR5.

At this time, the number of types of carboxylic acid esters produced is R
It changes depending on the combination of 4 and R5, the symmetry of 1li3-, etc.

Further, a carboxylic acid anhydride represented by the above formula [1],
When the cyclic ether represented by the formula [41] reacts without side reactions, R12GO0C:R6R7-(GR8R9), l-0R
IOR11OGOR13 (wherein R12 and R13 represent R1 or R2) It is possible to produce a carboxylic acid ester or a mixture thereof. When the cyclic ether represented by the formula 41 is produced for a long time without side reactions, for example, the cyclic ether represented by the general formula of the following formula (where P represents an integer of 1 or more) It is possible to produce polyesters such as polyester.

In the method of this invention, the reaction can generally be carried out by the following method.

The carboxylic acid anhydride ([AI acid component and the ether ([B] molar ratio of the acid component ([B]/[A]
) Ji, usually 0.01-100, preferably 0.
1 to 10. When the reaction is carried out in a continuous manner, the reaction may be carried out by continuously supplying them as appropriate so that the molar ratio falls within this range. If this molar ratio is less than 0.01, unreacted [A]! On the other hand, if it exceeds 100, the amount of unreacted [B] acid component increases, which may be disadvantageous in terms of economy and productivity.

The method of expressing the usage ratio of the acid catalyst ([C1 component)] differs depending on the reaction operation method or reaction method, such as batch type or various continuous flow type, and the usage ratio depends on the type of acid catalyst used, It cannot be uniformly defined or expressed because it varies depending on the form and various other conditions. Therefore, the usage ratio for the formula [01] is shown below for illustrative purposes only.

That is, when the above reaction is carried out batchwise, or when a reaction method is used in which the catalyst and the reactants are passed through at the same time, and the acid substance itself as the acid catalyst or the effective acid substance component in the acid catalyst is When using an acid catalyst that can be defined by a molecular formula or a compositional formula, the ratio of the acid catalyst used is ((number of moles of protic acid + number of moles of aprotic acid) / ([A] number of moles of acid component [ The value of B] (number of moles of acid component)) can be selected within a range of, for example, usually about 0.001 to about 10, preferably about 0.01 to about 2. If this value is smaller than o or oot, the reaction rate may not be sufficient, while if it exceeds 10, it may be disadvantageous in terms of economy, productivity, etc.

In addition, when using an acid catalyst for which the above expression is difficult or inappropriate for a solid acid or a mixture containing an acid component, the proportion used should be adjusted as appropriate. The reaction can be carried out. for example,
When using a solid acid catalyst such as a solid acid as the acid catalyst, (weight of solid acid (g)/(weight of the above [Al component (g) + weight of the [B] acid component (g))] ) is
Usually, it can be set to about 0.001 to 10, preferably about 0.01 to 2. This value is 0.0
If it is less than 01, the reaction rate may not be sufficient, while if it exceeds 10, it may be disadvantageous in terms of economy, productivity, etc.

In addition, when a solid acid catalyst such as a solid acid catalyst or a fixed acid catalyst is used in a packed system such as a fixed bed and the reaction is performed by a continuous flow method, the usage ratio is expressed in terms of space velocity. Using this expression, the reaction can be expressed as a double star space velocity (WH3V, or (1
The above rA] Al component B] total weight of acid component supplied per hour/(weight of acid catalyst used)] is, for example, usually about 0.001 to 100 hr''1, preferably 0.1
It can be carried out limited to about 50 hrl. If this value is less than 0.001, it may be disadvantageous in terms of economy and productivity, while if it exceeds 100, the reaction rate may not be sufficient and productivity may decrease.

As this reaction method or reaction characteristic method, in addition to the batch method and continuous flow method described above, various methods such as semi-batch method, pulse method, intermittent flow method, circulation method, recirculation method can be used. These can be used in appropriate combinations as necessary.

In such a case, the [Al component, the [B] acid component, the acid catalyst, or if necessary, the following components such as a solvent and a diluent such as an inert gas may be added simultaneously or separately, or as appropriate. It is also possible to carry out the reaction by dividing it and supplying it to the reaction system.

The reaction temperature in carrying out the above reaction cannot be uniformly specified depending on the type of catalyst used, etc., but is usually 30 to 350℃.
℃, preferably in the range of 50 to 250℃. If the reaction temperature is less than 50°C, the reaction rate may not be sufficient, while if it is higher than 350°C, disadvantages such as an increase in side reactions such as decomposition reactions and a shortened catalyst life may occur. There is.

The reaction pressure is not particularly limited and can be selected from reduced pressure, normal pressure, the autogenous pressure of the reaction system, and increased pressure, but is usually normal pressure to 100 atm (gauge pressure), preferably normal pressure. The pressure can be set in the range of pressure to 50 atmospheres (gauge pressure).

Note that the reaction can be carried out in the presence of a solvent and/or a diluent such as an inert gas, and/or an additive, if necessary.

This solvent is not particularly limited as long as it does not substantially interfere with the reaction, and various solvents can be used. Specific examples of such solvents include, for illustrative purposes only, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, and trimethylbenzene; aliphatic hydrocarbons such as hexane, octane, decane, and hexadecane; Naphthenic hydrocarbons such as dichlorohexane, methylcyclohexane, and decalin; Esters such as ethyl acetate, butyl acetate, methyl benzoate, phenyl acetate, and cyclohexyl acetate; Ketones such as acetone, ethyl methyl ketone, benzophenone, and acetophenone Nitriles such as acetonitrile and benzonitrile; Various inert solvents such as halogenated hydrocarbons such as methylene chloride, carbon tetrachloride, tetramethylethylene, chlorobenzene, dichlorobenzene, fluorobenzene, fluorotoluene, and chlorotoluene. can be mentioned.

In addition, these can be used individually or in combination of two or more types.

The inert gas is not particularly limited as long as it does not interfere with the reaction, and specific examples of such gases are shown merely for illustrative purposes, such as helium, argon,
Nitrogen, carbon dioxide, -carbon oxide, hydrogen, methane, ethane, etc. can be mentioned.

In addition, these may be used individually by 1 type, or may be used as a mixture of 2 or more types.

Examples of the additives include water, alcohols, active hydrogen-containing compounds such as phenols and acetylacetones, and unsaturated compounds such as olefins, dienes, and acetylenes.

These additives can be used alone or in appropriate combinations of two or more in appropriate amounts to improve the activity, selectivity, and life of the catalyst, and to improve the efficiency of the reaction.

There is no particular restriction on the procedure for one reaction when carrying out the reaction, and it is possible to carry out the reaction by supplying each of the above components to the reactor simultaneously, separately, or in divided order in various orders, For example, when performing a reaction batchwise,
Usually, an appropriate amount of the above [A] is placed in a reactor purged with inert gas etc.
] Acid component [B] Acid component If necessary, supply these and the above solvent.

Next, the acid catalyst or its solution is added, and if necessary, the reaction is carried out by further pressurizing with the inert gas.

There are no particular restrictions on the state of the reaction system during the reaction, and it may be any of the following states: gas, liquid, solution, or dispersed state, gas-liquid coexistence state, liquid cylinder coexistence state, gas-solid coexistence state, gas-liquid-solid coexistence state. However, it is usually preferable to carry out the reaction while at least a portion of the reaction raw materials are kept in a liquid phase.

By the method described above, it is possible to obtain a reaction product containing one or more carboxylic acid esters as the desired product.

The produced carboxylic acid ester is obtained by subjecting the obtained reaction product liquid to appropriate post-treatments such as filtration, washing, distillation, extraction, etc., as necessary. Other components present therein, such as the used catalyst, solvent, additives, unreacted raw materials, and by-products, can be appropriately separated and removed, purified, and recovered as a product.

[Effects of the Invention] According to the present invention, a novel and practical reaction is used that produces only carboxylic acid ester without substantially producing water, so it is different from the conventional carboxylic acid that produces water. Compared to methods using condensation reactions with alcohols, post-treatment steps such as distillation of the product can be significantly simplified, the efficiency is high, and the thermodynamic equilibrium of the reaction is also significantly improved. It has advantages such as being advantageous.

Therefore, it is possible to provide a novel and industrially advantageous method for producing carboxylic acid esters that is significantly superior in terms of reaction and process efficiency, productivity, economy, product quality, and the like.

[Example] (Example 1) A 100 cc autoclave manufactured by Hastelloy-C was charged with 2:12 g of ethyl ether, 30.83 g of acetic anhydride, and 4.25 g of boron fluoride: BF3.0(Et)z. . The reactor was pressurized with nitrogen to 30 Kg/cm@2. Next, the reactor was heated to 150°C and a reaction was carried out for 2 hours. After the reaction was completed, it was cooled, and the contents of the reactor were taken out and analyzed by gas chromatography. Analysis shows that this reaction yields 8 for acetic anhydride.
Ethyl acetate was produced with a yield of 8.6%.

(Examples 2 to 5) The same operation as in Example 1 was performed except that the catalyst 1 reaction conditions were changed as shown in the table. Table 1 shows the results.

Table 1 (Example 6) Catalyst Preparation - Amo 0.5II in 830mM aqueous phosphoric acid solution
An/l Zr0GJlz [zirconium oxychloride] aqueous solution 855 mM was slowly added while stirring,
The resulting precipitate was left overnight, thoroughly washed by repeated filtration and water washing, and then dried at 110° C. for 24 hours. 40 g of the obtained amorphous zirconium phosphate was refluxed for 48 hours in two portions of 10 moJ1/u phosphoric acid, thoroughly washed with water, and then dried at 110° C. to obtain crystalline zirconium phosphate.

1 Reaction 1 5.0 g of zirconium phosphate obtained as above
was filled into a glass reaction tube, and 101/h of nitrogen was added at normal pressure.
Store at 300°C for 2 hours at r. After that, normal pressure, 18
0°C, ethyl ether/acetic anhydride (weight ratio 4/6)
10 g/hr of the mixed solution is supplied together with 7 n/hr of nitrogen as a diluent. The liquid flowing out from the catalyst layer was analyzed by gas chromatography.

Analysis shows that this reaction yields 86.3% for acetic anhydride.
% yield of ethyl acetate.

(Example 7) The same procedure as in Example 1 was carried out except that 18.4 g of dimethyl ether was used instead of ethyl ether. Analysis shows that this reaction yields 31.1% with respect to acetic anhydride.
Methyl acetate was produced in a yield of .

(Example 8) Feel 2: 4.87 as a catalyst in Example 7
The same procedure as in Example 7 was carried out except that g was used.

Analysis shows that in this reaction, 4fi for acetic anhydride,
Methyl acetate was produced with a yield of 91%.

(Example 9) In Example 1, propionic anhydride 3 was used instead of acetic anhydride.
The same procedure was performed except that 9.0 g was used. Analysis shows that this reaction yields 85.8% for propionic anhydride.
% yield of ethyl propionate.

(Example 10) A 100 cc autoclave manufactured by Hastelloy-C was charged with 39.0 g of butyl ether, 47.49 g of acetic anhydride, and 24.25 g of boron fluoride: BF3.0 (Et). After heating the reactor to 150° C., the reaction was carried out for 2 hours.

After the reaction was completed, it was cooled, and the contents of the reactor were taken out and analyzed by gas chromatography. Analysis shows that this reaction yields 84% of acetic anhydride.
．． Butyl acetate was produced with a yield of 3%.

(Example 11) Phthalic anhydride 30 was used instead of acetic anhydride in Example 1O.
．． 0 g, ethyl ether instead of butyl ether 22.
The same procedure was performed except that 2 g was used. Analysis showed that the reaction produced diethyl phthalate in a yield of 73.4% relative to phthalic anhydride.

(Example 12) Maleic anhydride 4 was used instead of acetic anhydride in Example 1O.
4.4 g, 22 ethyl ether instead of butyl ether
．． The same procedure was performed except that 2 g was used.

Analysis shows that in this reaction, 7
Diethyl maleate was produced in a yield of 1.1%.

(Example 13) Phthalic anhydride 44 was used instead of acetic anhydride in Example 1O.
．． The same procedure was carried out except that 4 g was used. Analysis showed that the reaction produced dibutyl phthalate in a yield of 88.5% based on phthalic anhydride.

Claims (1)

[Claims] (1) A method for producing a carboxylic acid ester, which comprises reacting a carboxylic anhydride and an ether in the presence of an acid catalyst.