JPH06345692A - Production of alpha-hydroxy isobutyric acid ester - Google Patents

Abstract

PURPOSE:To industrially advantageously obtain the subject ester useful for the production of a methacrylate ester in high yield and in high selectivity by reacting alpha-hydroxy isobutyric acid with an alcohol in the presence of a catalyst in a liquid phase. CONSTITUTION:alpha-Hydroxy isobutyric acid is reacted with an alcohol in the presence of an insoluble solid acid catalyst in a liquid phase to obtain the objective ester. An oxide (e.g. antimony trioxide) containing an element such as Sb, Zr or Bi is preferably used as the catalyst, and the reaction is preferably performed under pressure.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an α-hydroxyisobutyric acid ester from an α-hydroxyisobutyric acid amide and an alcohol. α-Hydroxyisobutyric acid ester is an industrially important compound used for the production of methacrylic acid ester by dehydration and the production of α-amino acid by aminolysis.

[0002]

2. Description of the Related Art As a method for producing α-hydroxyisobutyric acid ester, a method for producing α-hydroxyisobutyric acid ester directly from acetone cyanohydrin using an acid catalyst is known. For example, US Patent No. 204182.
No. 0 publication describes acetone cyanohydrin, sulfuric acid and alcohol.
A method is disclosed in which, after hydrolyzing and esterifying the alcohol and the ester at a temperature of 100 ° C. or lower, anhydrous sodium sulfate is added and distilled. However, in this method, the yield is low and a large amount of methyl methacrylate is by-produced. Japanese Patent Laid-Open No. 4-2
No. 30241 discloses a method in which acetone cyanohydrin and alcohol are reacted in the presence of hydrogen chloride, and the resulting 2-hydroxy-2-methyliminopropionitrile methyl ester hydrochloride is reacted with water. ing. According to these methods, a large amount of ammonium sulfate or ammonium chloride is produced as a by-product, the treatment thereof requires a great deal of cost, and it is difficult to separate and produce the desired product carboxylic acid ester with high purity. Also, due to the use of sulfuric acid or hydrochloric acid, the reactor must use expensive corrosion resistant materials.

As a method for producing an .alpha.-hydroxyisobutyric acid ester from .alpha.-hydroxyisobutyric acid amide, JP-A No. 52-3015 discloses that at least a part of an anion is a residue of an acid forming an ester. A method is described for carrying out the reaction in the presence of said metal carboxylate. However, this method has a low yield of α-hydroxyisobutyric acid ester, is not practical, and is difficult to recover the catalyst. In addition, JP-A-2-268137, JP-A-3-48637, and JP-A-3-1412
No. 42, Japanese Patent Publication No. 3-53292, etc.
A method for producing α-hydroxyisobutyric acid ester and formamide by reacting hydroxyisobutyric acid amide and formic acid ester or alcohol and carbon monoxide is described. However, these methods require the use of expensive formic acid ester or the use of highly toxic carbon monoxide at high pressure.

[0004]

In the prior art, when an α-hydroxyisobutyric acid ester is produced by esterification of α-hydroxyisobutyric acid amide, a large amount of auxiliary materials such as sulfuric acid and hydrochloric acid are required, Even when a catalyst is used, there are various industrial problems such as low yield and requiring a complicated purification process. An object of the present invention is to provide a method capable of industrially advantageously carrying out the production of an α-hydroxyisobutyric acid ester from an α-hydroxyisobutyric acid amide and an alcohol, specifically, an insoluble solid acid. It is intended to provide a novel method for producing an α-hydroxyisobutyric acid ester capable of producing an α-hydroxyisobutyric acid ester with a high yield and a high selectivity by using a as a catalyst.

[0005]

The present invention relates to a method for producing an α-hydroxyisobutyric acid ester, which comprises reacting an α-hydroxyisobutyric acid amide with an alcohol in the presence of an insoluble solid acid catalyst.

The present invention will be described in detail below. In the method of the present invention, an insoluble solid acid is used as a catalyst. Insoluble means that it is not substantially dissolved in the reaction system and the separation after the reaction is easy. Many oxides can be mentioned as a solid acid catalyst. For example, Sb, S
c, Y, La, Ce, Ti, Zr, Hf, V, Nb, T
a, Cr, Mo, W, Tc, Re, Fe, Co, Ni,
It is an oxide containing one or more metal elements selected from the group consisting of Cu, Al, Si, Sn, Pb and Bi. This scope of oxides of the invention also includes hydrated oxides. Preferably Sb, La, Ce, Ti, Zr,
V, Nb, Ta, Mo, W, Fe, Co, Ni, Cu,
An oxide containing one or more elements selected from the group consisting of Al, Si, Sn, Pb and Bi, particularly preferably selected from the group consisting of Sb, Bi and Zr.
Oxide containing one or more elements, and [A] S
at least selected from the group consisting of b, Zr and Bi
One element and [B] Na, K, Rb, Cs, Ca, S
r, Ba, Sc, Y, La, Ce, Ti, V, Nb, T
a, Cr, Mo, W, Mn, Fe, Co, Ni, Ru,
Os, Rh, Pd, Pt, Cu, Ag, Au, Zn, C
d, B, Al, Ga, In, Tl, Si, Ge, Sn,
Selected from the group consisting of Pb, P, S, Se and Te
It is an oxide containing one or more elements.

When the catalyst is composed of an oxide composed of two or more kinds of metal elements, its proportion can be varied within a wide range. For example, in the case of an oxide containing [A] Sb, Zr or Bi and another metal element, the atomic ratio can be changed to 10 or less, preferably 5 or less to the metal element 1 of [A].

As the catalyst of the present invention, either a commercially available oxide or a prepared one can be used. As a preparation method, any method known in this type of technical field can be used. The starting material of each component constituting the catalyst can be selected from many kinds of each component such as metal, oxide, hydroxide, chloride, inorganic acid salt, organic acid salt and the like. Further, it is possible to use a substance that can be converted into an oxide or a hydroxide by subjecting it to a chemical treatment, a firing treatment, or the like.

As the raw material for the antimony component, diantimony trioxide, diantimony tetroxide, diantimony pentoxide,
Antimonic acid, antimonate, antimony sulfide, antimony chloride or the like can be used. The product obtained by nitric acid oxidation of antimony metal may be used. As the zirconium component raw material, zirconium dioxide, zirconium acetylacetonate, zirconium chloride,
Zirconium oxychloride, zirconium oxynitrate, zirconium sulfate, zirconium (IV) isopropoxide and the like can be used. As the raw material of the iron component, metallic iron, ferrous oxide, ferric oxide, ferrosoferric oxide, iron nitrate,
Iron acetate, iron oxalate, etc. are used. As a raw material for the nickel component, metallic nickel, nickel oxide, nickel nitrate, nickel acetate, nickel oxalate, or the like is used. As the tungsten component raw material, metal tungsten, tungsten oxide, tungstic acid, tungsten chloride, or the like is used. Bismuth component raw materials include metal bismuth, dibismuth trioxide, bismuth chloride, bismuth nitrate,
Bismuth sulfate, bismuth oxalate, basic bismuth acetate, basic bismuth nitrate and the like can be used. The raw materials for the other components can be selected from many types such as oxides, hydroxides, chlorides and nitrates of the respective components. A catalyst is produced by mixing or coprecipitating these catalyst raw materials so that a desired composition ratio is obtained, drying and then calcining. It is desirable that the components constituting the catalyst are closely mixed and integrated. Further, since the catalyst activity of this type of catalyst develops upon calcination, it is desirable that the catalyst composition prepared to have a desired composition is calcined at a temperature of 150 to 1000 ° C. for 0.5 to 48 hours.
It is not clear what form the catalyst component has in the produced catalyst, but it is considered to be an oxide, a hydrated oxide, a hydroxide or a mixture or mixture thereof.

When the catalyst is an oxide of one element, for example, antimony oxide, diantimony trioxide is obtained by hydrolyzing antimony trichloride and then boiling it with an aqueous sodium carbonate solution. Antimony tetroxide is obtained by heating diantimony trioxide in air. Diantimony pentoxide is obtained by dissolving antimony in hydrochloric acid and adding concentrated nitric acid to the precipitate to heat the precipitate at 780 ° C. In the case of zirconium oxide, zirconium dioxide is obtained by hydrolyzing zirconium (IV) isopropoxide, followed by drying and firing. It can also be obtained by firing zirconium acetylacetonate. In the case of bismuth oxide, dibismuth trioxide can be obtained by firing bismuth oxalate or basic bismuth nitrate.

The catalyst may be used in any shape such as powder, sphere and pellet. The catalyst can also be used by being carried on a carrier. As the carrier, for example, activated carbon, alumina, silica or the like can be used. Since these catalysts are not easily dissolved in water, alcohol, etc., the catalysts can be easily recovered after the reaction.

In the reaction of the present invention, the reaction of α-hydroxyisobutyric acid amide and alcohol is carried out in the presence of the above catalyst. Typical examples of the alcohol used in the present invention include:
Methanol, ethanol, propanol, butanol,
Benzyl alcohol and the like can be mentioned. The amount of alcohol used is 1 to 50 relative to α-hydroxyisobutyric acid amide.
It is good to use it in a double mole, preferably in a range of 2 to 20 moles.

The reaction temperature is 150 to 250 ° C., preferably 180 to 230 ° C. If the temperature is lower than 150 ° C., the reaction rate becomes small, and if the temperature is higher than 250 ° C., the amount of by-products such as α-methoxyisobutyric acid ester and α-hydroxyisobutyric acid increases, which is not preferable. In the reaction of the present invention, it is preferable that water does not exist in the reaction system, but the reaction proceeds if the amount of water is 3 times or less the molar amount of α-hydroxyisobutyric acid amide.

The reaction pressure is appropriately determined according to the type and amount of alcohol used, the amount of water and the reaction temperature, but it is preferably 1 to 100 atm, preferably 10 to 70 atm.

This reaction can also be carried out in the presence of a solvent. For example, dioxane, tetrahydrofuran,
Examples thereof include n-hexane, cyclohexane, benzene and toluene. The reaction can be carried out by either a batch method or a continuous method, but industrially it is preferably a continuous method.

[0016]

EXAMPLES The method of the present invention will be described in more detail with reference to the following examples.

Example 1 21 g of α-hydroxyisobutyric acid amide, 48 of methanol
g, antimony trioxide (senarmontite) 4 as a catalyst
was charged into a 200 ml autoclave and the pressure was adjusted to 32
The reaction was carried out at a reaction temperature of 160 to 230 ° C. for 3 hours while stirring at atmospheric pressure. During this period, nitrogen gas was fed into the autoclave at a rate of 200 ml / min, and the produced ammonia was discharged from the autoclave together with the nitrogen gas. After the reaction, the reaction solution was cooled, the catalyst was filtered off, and the reaction product was analyzed by gas chromatography.

Example 2 The reaction was performed in the same manner as in Example 1 except that 4 g of diantimony trioxide (valentinite) was used as a catalyst.

Example 3 The reaction was carried out in the same manner as in Example 1 except that 4 g of diantimony tetroxide was used as a catalyst.

Example 4 The reaction was carried out in the same manner as in Example 1 except that 4 g of commercially available antimonic acid was used as a catalyst.

Example 5 Commercially available antimonic acid baked at 300 ° C. for 3 hours 4
The reaction was performed in the same manner as in Example 1 except that g was used as the catalyst.

Example 6 To 300 g of silica sol (SiO ₂ concentration: 20 wt%), 396 g of antimonic acid was added, evaporated to dryness with stirring, and then dried at 160 ° C. overnight. After that, firing was performed at 500 ° C. for 2 hours. The reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 7 930.5 g of 61% nitric acid was mixed with 843 ml of water and heated. 124.3 g of electrolytic iron powder is added little by little to this and melt | dissolved. After taking 324.4 g of diantimony trioxide powder and adding it to the nitric acid solution of iron while stirring, it is adjusted to PH1 with aqueous ammonia. The slurry is heated at 98 ° C. for 2 hours while stirring well. The solution was evaporated to dryness and then baked at 550 ° C. for 2 hours. When the fired product was analyzed, the composition was FeSbO ₄ . The reaction was performed in the same manner as in Example 1 except that 4 g of this oxide was used as a catalyst.

Example 8 930.5 g of 61% nitric acid was mixed with 843 ml of water and heated. 124.3 g of electrolytic iron powder is added little by little to this and melt | dissolved. Silica sol (SiO ₂ concentration 20 wt%) 1584
After taking g and adding to the above nitric acid solution of iron with stirring, 324.4 g of diantimony trioxide powder is added and stirred well. This slurry is adjusted to PH1 with aqueous ammonia while stirring well and heated at 98 ° C. for 2 hours. The solution was evaporated to dryness and then baked at 550 ° C. for 2 hours.
The reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Examples 9-11 Oxides of antimony and tungsten, antimony and lanthanum, and antimony and zirconium were prepared in the same manner as in Example 7. The reaction was performed in the same manner as in Example 1 except that 4 g of this oxide was used as a catalyst.

Example 12 The reaction was carried out in the same manner as in Example 1 except that 4 g of silica was used as a catalyst.

Examples 13 to 14 Example 7 using iron or lanthanum nitrate as a raw material
Each oxide was prepared in the same manner as in. The reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst. Table 1 shows the reaction results of Examples 1 to 14 above.

[0028]

[Table 1]

Example 15 Zirconium dioxide calcined at 350 ° C. for 2 hours 4
The reaction was performed in the same manner as in Example 1 except that the catalyst was used as the g catalyst.

Example 16 A reaction was performed in the same manner as in Example 1 except that 4 g of hydrated zirconium dioxide hydrate at 400 ° C. for 2 hours was used as a catalyst.

Example 17 46.8 g of zirconium (IV) isopropoxide and 32 g of methanol were mixed and stirred. After the solution solidified, it was dried at room temperature for 2 days and then calcined at 400 ° C. for 2 hours. The reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 18 The reaction was carried out in the same manner as in Example 1 except that 4 g of zirconium dioxide hydrate was used as a catalyst.

Example 19 73 g of zirconium oxynitrate was dissolved in 250 ml of water, and the silica sol (SiO ₂ concentration 20 wt.
%) 82g, and then add 28% ammonia water to pH
Prepared to 9.2. After this slurry was evaporated to dryness, it was calcined at 250 ° C. for 2 hours and then at 500 ° C. for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 20 80.8 g of iron (III) nitrate nonahydrate is dissolved in 300 ml of water. Zirconium oxynitrate dihydrate 10
After adding 6.8g, it adjusted to PH8 with 28% ammonia water. The precipitate formed is washed and then dried 40
Baking was performed at 0 ° C. for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Examples 21 to 24 Oxides of zirconium and cobalt, zirconium and lanthanum, zirconium and cerium, and zirconium and copper (atomic ratio of metal elements: 1/1) were prepared in the same manner as in Example 20. The reaction was carried out in the same manner as in Example 1 except that 4 g of these oxides were used as a catalyst.

Examples 25 to 27 Using cobalt, cerium or copper nitrate as a raw material, the respective oxides were prepared in the same manner as in Example 20. Except that 4 g of the obtained oxide was used as a catalyst,
The reaction was carried out in the same manner as in Example 1. Example 1 above
Table 2 shows the reaction results of 5 to 27.

[0037]

[Table 2]

Example 28 The reaction was carried out in the same manner as in Example 1 except that 4 g of bismuth oxide calcined at 400 ° C. for 2 hours was used as a catalyst.

Example 29 The reaction was carried out in the same manner as in Example 1 except that 4 g of bismuth oxalate calcined at 550 ° C. for 2 hours was used as a catalyst.

Example 30 Basic bismuth nitrate baked at 500 ° C. for 2 hours 4
The reaction was carried out in the same manner as in Example 1 except that g was used as the catalyst.

Example 31 80 g of bismuth nitrate was dissolved in 100 ml of 10% nitric acid and adjusted to pH 8 with ammonia water while stirring to precipitate bismuth hydroxide. After washing this precipitate with water,
It was dried at 110 ° C. for 24 hours. The dried product contained a part of hydroxide in addition to the oxide. Obtained oxide 4
The reaction was carried out in the same manner as in Example 1 except that g was used as the catalyst.

Example 32 70.4 g of bismuth nitrate was dissolved in 100 ml of 10% nitric acid, and silica sol (SiO ₂ concentration 20 wt.
%) 90.1 g was added. After the obtained slurry was evaporated to dryness, it was calcined at 250 ° C. for 2 hours and then at 600 ° C. for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 33 80.8 g of iron (III) nitrate nonahydrate is dissolved in 300 ml of water. After adding 58.7 g of basic bismuth nitrate, PH8 was prepared with 28% ammonia water. The formed precipitate was washed, dried and calcined at 400 ° C. for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Examples 34 to 37 Oxides of bismuth and cobalt, bismuth and lanthanum, bismuth and cerium, and bismuth and copper (atomic ratio of metal elements: 1/1) were prepared in the same manner as in Example 33. Example 1 except that 4 g of these oxides were used as catalysts
The reaction was carried out in the same manner as in. Examples 28-37 above
Table 3 shows the results of the reaction.

[0045]

[Table 3]

Example 38 The reaction was carried out in the same manner as in Example 1 except that commercially available silica-alumina was used as a catalyst.

Example 39 89.2 g of zinc nitrate hexahydrate was dissolved in 250 ml of water, and silica sol (SiO ₂ concentration 20 wt.
%) 90.1 g, and then P with 28% ammonia water
Prepared to H9. The slurry was washed with water and then dried overnight at 110 ° C. After that, preliminary firing was performed at 250 ° C. for 2 hours, and firing was performed at 500 ° C. for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 40 Metatungstic acid aqueous solution (WO ₃ content, 50.0 wt.
%) 158.9 g, while stirring, silica sol (SiO 2
₍₂ concentration: 20 wt%) 102.9 g was added and the mixture was evaporated to dryness. Then, it baked at 500 degreeC for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 40 86.6 g of lanthanum nitrate hexahydrate and 75.0 g of aluminum nitrate nonahydrate were dissolved in 300 ml of water, and pH 8 was adjusted with 28% ammonia water without stirring. The formed precipitate was washed with water and then dried overnight at 110 ° C. After that, preliminary firing was performed at 250 ° C. for 2 hours, and firing was performed at 500 ° C. for 2 hours. A reaction was performed in the same manner as in Example 1 except that 4 g of the obtained oxide was used as a catalyst.

Example 41 80.8 g of iron nitrate nonahydrate and 75.0 g of aluminum nitrate nonahydrate were dissolved in 300 ml of water and stirred with stirring.
The pH was adjusted to 8 with aqueous ammonia. The formed precipitate was washed with water and then dried overnight at 110 ° C. Then 2
Pre-baking was performed at 50 ° C. for 2 hours, and baking was performed at 500 ° C. for 2 hours. Except that 4 g of the obtained oxide was used as a catalyst,
The reaction was carried out in the same manner as in Example 1. Example 38 above
Table 4 summarizes the reaction results of ~ 41.

[0051]

[Table 4]

[0052]

According to the method of the present invention, in reacting α-hydroxyisobutyric acid amide with alcohol, an insoluble solid acid catalyst, particularly at least one element selected from the group consisting of antimony, zirconium and bismuth. By using an oxide containing a as a catalyst, it is possible to produce α-hydroxyisobutyric acid ester with high yield and high selectivity, and these catalysts are easy to recover the catalyst after the reaction is completed. Since it can be used repeatedly, its industrial significance is great. Further, the method of the present invention does not use an acid such as sulfuric acid or hydrochloric acid, and therefore does not require an expensive corrosion-resistant manufacturing apparatus.

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[Procedure amendment]

[Submission date] October 22, 1993

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[Claims]

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[0005]

Means for Solving the Problem The present invention provides a method for producing an α-hydroxyisobutyric acid ester, which comprises reacting an α-hydroxyisobutyric acid amide with an alcohol in a liquid phase in the presence of an insoluble solid acid catalyst. Regarding construction method.

[Procedure 3]

[Document name to be amended] Statement

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The reaction of the present invention comprises reacting α-hydroxyisobutyric acid amide with an alcohol in the presence of the above catalyst .
Perform in liquid phase . Representative examples of the alcohol used in the present invention include methanol, ethanol, propanol, butanol, benzyl alcohol and the like. The amount of alcohol used is 1 to 50 times mol, preferably 2 to 20 times mol, of the α-hydroxyisobutyric acid amide.

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The reaction pressure is appropriately determined depending on the type and amount of alcohol used, the amount of water, and the reaction temperature, but is 1 to 100 atm, preferably under pressure, particularly 10 to 7 atm.
It is advisable to carry out in the range of 0 atmosphere.

[Procedure Amendment 5]

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[0052]

According to the method of the present invention, in reacting α-hydroxyisobutyric acid amide with alcohol,
By using a solid acid catalyst insoluble in the liquid phase , particularly an oxide containing at least one element selected from the group consisting of antimony, zirconium and bismuth as a catalyst, it is possible to obtain a high yield of α-hydroxyisolate with high selectivity. In addition to the ability to produce butyric acid ester, these catalysts have great industrial significance because they can be easily recovered after the completion of the reaction and can be used repeatedly. Further, the method of the present invention does not use an acid such as sulfuric acid or hydrochloric acid, and therefore does not require an expensive corrosion-resistant manufacturing apparatus.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location B01J 23/10 X 8017-4G 23/18 X 8017-4G 23/30 X 8017-4G 23/72 X 8017- 4G 23/74 X 8017-4G 23/84 X 8017-4G C07C 67/20 9279-4H // C07B 61/00 300

Claims (3)

[Claims] 1. A method for producing an α-hydroxyisobutyric acid ester, which comprises reacting an α-hydroxyisobutyric acid amide with an alcohol in the presence of an insoluble solid acid catalyst. 2. The solid acid catalyst is Sb, Sc, Y, La, C.
e, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo,
W, Tc, Re, Fe, Co, Ni, Cu, Al, S
The production method according to claim 1, which is an oxide containing one or more elements selected from the group consisting of i, Sn, Pb and Bi. 3. A solid acid catalyst comprising at least one element selected from the group consisting of Sb, Zr and Bi and Na, K,
Rb, Cs, Ca, Sr, Ba, Sc, Y, La, C
e, Ti, V, Nb, Ta, Cr, Mo, W, Mn, F
e, Co, Ni, Ru, Os, Rh, Pd, Pt, C
u, Ag, Au, Zn, Cd, B, Al, Ga, In,
Tl, Si, Ge, Sn, Pb, P, S, Se and T
The production method according to claim 1, which is an oxide containing one or more elements selected from the group consisting of e.