JPH0899935A - Production of aromatic carbonic acid ester - Google Patents

Abstract

PURPOSE: To suppress the by-production of an o-hydroxyaromatic carboxylic acid aryl ester in the production of an aromatic carbonic acid ester by the reaction of an aromatic hydroxy compound with carbon monoxide and oxygen. CONSTITUTION: This process for the production of an aromatic carbonic acid ester is carried out by using a catalyst system composed of (A) one or more substances selected from palladium and palladium compounds, (B) one or more substances selected from lead compounds, (C) one or more halogenated compounds selected from quaternary ammonium halides and quaternary phosphonium halides and optionally further (D) one or more substances selected from copper and copper compounds. The yield of the aromatic carbonic acid ester per unit palladium (turn-over number of palladium) can be improved by the use of the catalyst.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing an aromatic carbonic acid ester using a specific catalyst system. Aromatic carbonic acid esters, especially diphenyl carbonate, are useful as raw materials for polycarbonate and the like.

[0002]

2. Description of the Related Art Conventionally, a method of reacting an aromatic hydroxy compound with phosgene has been used as a method for producing an aromatic carbonic acid ester. However, this method is not preferable because phosgene is highly toxic. Therefore, as a method that does not use phosgene, a method of producing an aromatic carbonic acid ester from an aromatic hydroxy compound and carbon monoxide and oxygen has been proposed.

As a catalyst in this method, Japanese Examined Patent Publication No. 56-3
No. 8144 discloses a palladium compound and III of the periodic table.
Method using a compound containing a metal of group A, IVA, VA, VIA, IB, IIB, VIB or VIIB and a base; JP-B-56-3
8145 discloses a method using a palladium compound, a manganese complex or a cobalt complex, a base and a desiccant;
1-165551, a method using a palladium compound, iodine and zeolites; JP-A-2-104564,
Palladium compound, divalent or trivalent manganese compound,
Method using tetraalkylammonium halide and quinones; JP-A-2-142754 discloses a method using a palladium compound, a divalent or trivalent cobalt compound, a tetraalkylammonium halide and quinones; JP-A-525095. JP-A-5-39247 discloses a method using a palladium compound, a copper compound, a quinone and an onium halide; JP-A-5-39247 discloses a method using palladium or a palladium compound, a cobalt compound halide and a basic compound. JP-A-58961 discloses a method of using one or more of palladium and a palladium compound, a cobalt compound and an alkali metal halide;
In the publication, one metal co-catalyst selected from palladium, quaternary ammonium salt, cobalt, iron, cerium, manganese, molybdenum, samarium, vanadium, chromium and copper, and aromatic ketone, aliphatic ketone, aromatic A method using a catalyst comprising an organic cocatalyst selected from polycyclic hydrocarbons; JP-A-6-9505 discloses a method using a palladium compound, a cerium compound, and a quaternary ammonium salt; JP-A-6-41020. In the publication, a method using a palladium compound, a metal cocatalyst selected from manganese, cobalt, and copper and a nitrile compound; JP-A-6-172268 discloses a palladium compound, a pentacoordinate complex of cobalt, and a quaternary onium salt. JP-A-6-172269 discloses an inorganic cocatalyst selected from a palladium compound, cobalt, manganese and copper, a quaternary onium salt, and terpyridine. A method using an organic cocatalyst, such as emissions are described. In the examples described in the above publications, the yield of aromatic carbonic acid ester per palladium (turnover number of palladium) is 700.
However, the catalytic activity was not always sufficient.

[0004]

The inventors of the present invention conducted a supplementary test using a conventional metal cocatalyst using phenol as a substrate, and found that no matter which catalyst was used, aroma was obtained as a by-product. O-hydroxy aromatic carboxylic acid aryl esters, which are structural isomers of group carbonic acid esters, for example:
Phenyl salicylate was formed. Generally, the isomer is
It is a compound that is extremely difficult to separate from aromatic carbonates by distillation and the like. The present invention is intended to provide an efficient method for producing an aromatic carbonic acid ester, which can reduce the production amount of such a difficult-to-separate by-product and can obtain a large palladium turnover number. Is.

[0005]

Means for Solving the Problems In the method for producing an aromatic carbonic acid ester by reacting an aromatic hydroxy compound with carbon monoxide and oxygen, the present inventors selected from (A) palladium and a palladium compound. More than one
The use of a catalyst system comprising (B) one or more kinds selected from lead compounds and (C) one or more halides selected from quaternary ammonium halides and quaternary phosphonium halides enables efficient aromaticity. It has been found that carbonic acid esters are produced and that by-products of o-hydroxyaromatic carboxylic acid aryl esters are suppressed as compared to conventional catalyst systems. In addition, it was surprisingly found that when the amount of palladium used was reduced in the catalyst system of the present invention, the turnover number of palladium was significantly improved. Although a large amount of a nuclear halide of an aromatic hydroxy compound is by-produced in the above catalyst system, further studies were conducted to suppress the by-product. As a more preferable system, (C) was a quaternary ammonium halide. It has been found that the nuclear halogenation of an aromatic hydroxy compound can be significantly suppressed by adding one or more selected from (D) copper and a copper compound to the catalyst system which is

[Detailed Description of the Invention] 1. Reaction Raw Materials (1) Aromatic Hydroxy Compound The aromatic hydroxy compound used in the present invention is an aromatic mono- or polyhydroxy compound, for example, phenol; cresol, xylenol, trimethylphenol, tetramethylphenol, ethylphenol, propylphenol, Substituted phenols such as methoxyphenol, ethoxyphenol, chlorophenol, dichlorophenol, bromophenol, dibromophenol and their isomers; substituted naphthols such as naphthol, methylnaphthol, ethylnaphthol, chloronaphthol, bromonaphthol and their isomers body;
Various bisphenols such as 2,2-bis (4-hydroxyphenyl) propane; various biphenols; various heteroaromatic hydroxy compounds and their isomers, and their substitution products with alkyl, halogen and the like. Of these, phenol is particularly preferred.

(2) Carbon monoxide Carbon monoxide used in the present invention is not only highly pure, but also diluted with other gases such as nitrogen, argon, carbon dioxide and hydrogen, which do not adversely affect the reaction. You can use it even if there is.

(3) Oxygen The oxygen used in the present invention is not only high-purity oxygen,
It is also possible to use one diluted with air or another gas that does not adversely influence the reaction, such as nitrogen, argon, carbon dioxide, or hydrogen.

2. Catalyst The catalyst used in the reaction of the present invention is (A)
Among the components listed in (B) and (C), at least one component is selected from each of them and contains a system in combination. A more preferable reaction system further contains at least one of the following components (D). (A) Palladium or palladium compound Palladium or palladium compound used in the present invention is palladium black; supported palladium such as palladium / carbon, palladium / alumina, palladium / silica; palladium chloride, palladium bromide, palladium iodide, palladium sulfate. Inorganic salts of palladium such as palladium nitrate; organic acid salts of palladium such as palladium acetate and palladium oxalate. In addition, acetylacetonato palladium (II) and palladium complex compounds in which carbon monoxide, nitriles, amines, phosphines, olefins, etc. are coordinated with palladium, such as PdCl ₂ (PhCN) ₂ and PdCl ₂ (PPh ₃ ) ₂ , P
d (CO) (PPh ₃ ) ₃ , [Pd (NH ₃ ) ₄ ] Cl ₂ ,
_{Pd (C 2 H 4) (} PPh 3) 2, [(η 3 -C 3 H 5) Pd
Cl] ₂ , Pd (DBA) ₂ , Pd ₂ (DBA) ₃ · CHC
l ₃ [DBA represents dibenzylideneacetone], etc.
Alternatively, it is also possible to use a mixture of palladium and a compound such that these complex compounds are formed in the reaction system. Of these, palladium / carbon and palladium acetate are preferable. The amount of the palladium component used in the reaction is 10 ⁻⁷ to a molar ratio with respect to the aromatic hydroxy compound.
It is preferably in the range of 10 ⁻² , particularly preferably in the range of 10 ⁻⁶ to 10 ⁻³ . In the catalyst system of the present invention,
Since the smaller the amount of palladium used, the larger the turnover number of palladium, it is preferable to use a smaller amount of palladium from the viewpoint of catalyst cost, but if it is too small, the aromatic hydroxy compound of the aromatic carbonic acid ester will be used. The standard yield decreases, and it becomes difficult to recover the aromatic carbonate.

(B) Lead Compound The lead compound used in the present invention is preferably one which is soluble in the liquid phase under the reaction conditions, such as PbO, Pb ₃ O ₄ ,
Lead oxides such as PbO ₂ ; Pb (OAc) ₂ , Pb (OA
c) ₄ , lead organic acid salts such as Pb (C ₂ O ₄ ), Pb (OCOC ₂ H ₅ ) ₂ ; inorganic lead salts such as Pb (NO ₃ ) ₂ and PbSO ₄ ; Pb (OMe) ₂ , Pb (OPh) _{2 and} other alkoxy and aryloxy lead, and lead phthalocyanine and other lead complex compounds may be mentioned. Of these, lead compounds represented by lead oxides and Pb (OR) ₂ [R represents an acyl group having 1 to 4 carbon atoms in the alkyl group or an aryl group having 6 to 10 carbon atoms] are preferable. The amount of the lead compound used in the reaction is not particularly limited, but it is preferably in the range of 10 ^-4 to 10 ^-1 and preferably in the range of 10 ^-4 to 10 ^-2 with respect to the aromatic hydroxy compound. It is particularly preferable that

(C) Halide The halide used in the present invention is a quaternary ammonium halide or a quaternary phosphonium halide,
The following formula: R ¹ R ² R ³ R ⁴ NX or R ¹ R ² R ³ R ⁴ PX [In the formula, R ^{1 to} R ⁴ represent an alkyl group or an aryl group having 1 to 10 carbon atoms, and each is the same group. Or different groups may be used. X represents halogen. ] It is a compound represented by these. In particular, bromide is preferable, and examples thereof include tetra-n-butylammonium bromide and tetraphenylphosphonium bromide. The amount of the halide used in the reaction is not particularly limited, but it is preferably in the range of 10 ^-4 to 1 and preferably in the range of 10 ^-3 to 10 ^-1 with respect to the aromatic hydroxy compound. Is particularly preferable.

(D) Copper or Copper Compound The copper or copper compound used in the present invention is a monovalent or divalent copper compound and metallic copper. Specifically, Cu
Organic acid salts of copper such as (OAc) ₂ , Cu (NO ₃ ) ₂ and CuS
Inorganic acid salts of copper such as O ₄ , CuBr, CuBr ₂ , CuC
1, copper halides such as CuCl ₂ , Cu ₂ O, CuO
Examples thereof include copper oxides such as Cu, copper alkoxides such as Cu (OPh) ₂ and Cu (OMe) ₂ , complex compounds of copper such as phthalocyanine copper, copper powder, and metallic copper such as copper wires. Among these, organic acid salts of copper, copper halides, copper oxides and metallic copper are preferable. The amount of copper or copper compound used in the reaction is not particularly limited, but it is preferably in the range of 10 ^-4 to 10 ^{-1 in} molar ratio with respect to the aromatic hydroxy compound,
Particularly, it is preferably in the range of 10 ⁻⁴ to 10 ⁻² .

3. Reaction conditions In the reaction, the above-mentioned aromatic hydroxy compound and the above-mentioned components (A), (B) and (C), and in a more preferable reaction system, a catalyst comprising the component (D) is charged into a reaction device to form carbon monoxide. And pressurized with oxygen and heated. The absolute pressure during the reaction is 1 to 500 atm in total pressure,
It is preferably in the range of 1 to 150 atm. From the viewpoint of safety, the composition ratio of carbon monoxide and oxygen is preferably outside the explosion range. The partial pressures of carbon monoxide and oxygen are 30-100 atm and 1-10, respectively.
Atmospheric pressure is preferred. Reaction temperature is 20-300
C., preferably in the range of 80 to 250.degree. The reaction time varies depending on the reaction conditions, but is usually several minutes to several hours. During the reaction, aromatic diols such as hydroquinone used in conventional catalyst systems, quinones which are oxidation products thereof, and organic additives such as amines may be added to the reaction system. Further, as the solvent, for example, an inert solvent such as hexane, heptane, cyclohexane, benzene, toluene, xylene, methylene chloride, chloroform, chlorobenzene, diethyl ether, diphenyl ether, tetrahydrofuran, dioxane, acetonitrile can be used. Since the starting aromatic hydroxy compound may serve as the reaction solvent, it is not necessary to use another solvent at this time.

[0014]

The present invention will be described in detail below with reference to examples and comparative examples. Example 1 In a Hastelloy autoclave having an internal volume of 40 ml, 3.01 g (32 mmol) of phenol and 2.7 mg (.
012 mmol), lead (II) oxide 2.8 mg (0.012 mmo)
l), tetrabutylammonium bromide 78.1 mg (0.2
(4 mmol) was added and the system was replaced with carbon monoxide, then carbon monoxide (60 atm) and dry air (30 atm) were introduced, and the mixture was stirred and mixed at 100 ° C. for 3 hours with a stir bar. After completion of the reaction, the gas phase and the liquid phase were quantitatively analyzed by gas chromatography. As a result, diphenyl carbonate was obtained in a yield of 6.75% (1.08 mmol) based on phenol. Phenyl salicylate 0.74% relative to diphenyl carbonate,
46.7% of tetrabutylammonium bromide used by bromophenol (total of ortho and para isomers, meta isomer not observed), carbon dioxide 0.30 mmo
l was a byproduct.

Examples 2 to 5 Instead of lead (II) oxide, various lead compounds were added to 0.01% each.
The reaction was performed in the same manner as in Example 1 except that 2 mmol was used. Table 1 shows the lead compounds used, the yield of the produced diphenyl carbonate on phenol, the by-product rate of phenyl salicylate on diphenyl carbonate, the production rate of bromophenol on tetrabutylammonium bromide, and the amount of carbon dioxide by-product. Show.

[0016]

[Table 1]

Example 6 The reaction was performed in the same manner as in Example 1 except that 25.5 mg (0.012 mmol Pd) of 5% palladium / carbon was used instead of palladium acetate. As a result, diphenyl carbonate was obtained in a yield of 8.38% (1.33 mmol) based on phenol. Phenyl salicylate is 0.67% to diphenyl carbonate, 54.0% to tetrabutylammonium bromide used for bromophenol (total of ortho and para isomers, meta isomer is not observed), carbon dioxide Was a by-product of 0.48 mmol.

Example 7 A reaction was performed in the same manner as in Example 1 except that 100.6 mg (0.24 mmol) of tetraphenylphosphonium bromide was used instead of tetrabutylammonium bromide. as a result,
Yield of diphenyl carbonate to phenol is 8.00%
Obtained at (1.29 mmol). Phenyl salicylate is 0.62% relative to diphenyl carbonate, and bromophenol is 53.53 relative to the tetraphenylphosphonium bromide used.
2% (total of ortho and para isomers, meta isomer not observed), carbon dioxide 0.46 mmol by-product.

Example 8 The same operation as in Example 1 was performed except that 0.6 mg (0.003 mmol) of copper (II) acetate monohydrate was added. As a result, the yield of diphenyl carbonate based on phenol was 8.28.
% (1.32 mmol). As by-products, phenyl salicylate was 0.83% with respect to diphenyl carbonate, and bromophenol was used with 18.3% with respect to tetrabutylammonium bromide (the total of the ortho and para forms,
A meta form was not observed), and 0.38 mmol of carbon dioxide was produced.

Examples 9 to 13 Reactions were carried out in the same manner as in Example 8 except that 0.012 mmol of various copper compounds were used instead of copper (II) acetate monohydrate. The type of copper compound used, the yield of diphenyl carbonate produced with respect to phenol, the by-product rate of phenyl salicylate with respect to diphenyl carbonate, the production rate of tetrabromoammonium bromide with bromophenol, and the amount of carbon dioxide by-product were displayed. 2 shows.

[0021]

[Table 2]

Example 14 The reaction was performed in the same manner as in Example 8 except that 25.5 mg (0.012 mmol Pd) of 5% palladium / carbon was used instead of palladium acetate. As a result, diphenyl carbonate was obtained in a yield of 9.12% (1.46 mmol) based on phenol. As by-products, phenyl salicylate was 0.88% with respect to diphenyl carbonate, and 15.0% was used with bromophenol against tetrabutylammonium bromide (the total of ortho and para isomers, and meta isomers were not observed). ), 0.45 mmol of carbon dioxide was produced.

Comparative Example 1 A reaction was carried out in the same manner as in Example 1 except that 2.9 mg (0.012 mmol) of manganese (II) acetate tetrahydrate was used instead of lead (II) oxide. As a result, diphenyl carbonate was obtained in a yield of 9.05% (1.44 mmol) based on phenol, but phenyl salicylate was 4.44% based on diphenyl carbonate, and tetrabutylammonium bromide used by bromophenol was obtained. On the other hand, 100% (the total of the ortho form and the para form, the meta form was not observed), and 1.94 mmol of carbon dioxide was by-produced.

Comparative Example 2 The reaction was carried out in the same manner as in Example 1 except that 3.0 mg (0.012 mmol) of cobalt (II) acetate tetrahydrate was used instead of lead (II) oxide. As a result, diphenyl carbonate was obtained in a yield of 1.26% (0.20 mmol) with respect to phenol, but phenyl salicylate was 9.05% with respect to diphenyl carbonate and 0.15 mmol of carbon dioxide was by-produced. No formation of bromophenol was observed.

Comparative Example 3 Example 1 was repeated except that 4.0 mg (0.012 mmol) of cerium (III) acetate monohydrate was used instead of lead (II) oxide.
The reaction was performed in the same manner as in. As a result, diphenyl carbonate was obtained in a yield of 6.02% (0.96 mmol) based on phenol, but phenyl salicylate was 3.82% based on diphenyl carbonate, and tetrabutylammonium bromide used by bromophenol was obtained. On the other hand, 9.9% (total of ortho and para isomers, meta isomer not observed), and 0.18 mmol of carbon dioxide was by-produced.

Comparative Example 4 The reaction was carried out in the same manner as in Example 1 except that tetrabutylammonium bromide was not used. As a result, the yield of diphenyl carbonate was 0.50% based on phenol.

Comparative Example 5 A reaction was carried out in the same manner as in Example 1 except that 28.6 mg (0.24 mmol) of potassium bromide was used instead of tetrabutylammonium bromide. As a result, diphenyl carbonate was obtained with a yield of 1.54% (0.25 mmol) based on phenol, but phenyl salicylate was 2.60% based on diphenyl carbonate and based on potassium bromide used by bromophenol. 22.9% (total of ortho and para isomers, meta isomer not observed), and 0.18 mmol of carbon dioxide was by-produced.

Example 15 12.23 g (130 mmol) of phenol, 4.26 mg (2.0 μmol P of Phenol / Carbon (manufactured by NEC Chemcat)) in a Hastelloy autoclave having an internal volume of 50 ml.
d), lead (II) oxide 10.71 mg (0.048 mmol), tetrabutylammonium bromide 322.4 mg (1.0 mmo)
After l) was added and the system was replaced with carbon monoxide, 60 atm of carbon monoxide and 30 atm of dry air were introduced, and the mixture was stirred and mixed at 100 ° C. for 3 hours using a stir bar. After completion of the reaction, the gas phase and the liquid phase were quantitatively analyzed by gas chromatography. As a result, diphenyl carbonate was obtained in a yield of 4.54% with respect to phenol (2.95 mmol, palladium turnover number 1475). As a by-product, phenyl salicylate is 0.5 relative to diphenyl carbonate.
8%, 43.6% with respect to tetrabutylammonium bromide used by bromophenol (total of ortho and para forms, meta form not observed), carbon dioxide 0.3.
It was 8 mmol.

Examples 16 to 19 The reaction was performed in the same manner as in Example 15 except that the amounts of 5% palladium / carbon and tetrabutylammonium bromide used were changed. Palladium / carbon used, amount of tetrabutylammonium, yield of diphenyl carbonate, turnover number (TN) of palladium, by-product ratio of phenyl salicylate to diphenyl carbonate, production ratio of bromophenol to tetrabutylammonium bromide. Table 3 shows the by-product amounts of carbon dioxide and carbon dioxide.

[0030]

[Table 3]

Example 20 A reaction was performed in the same manner as in Example 15 except that 0.45 mg (2.0 μmol) of palladium acetate was used instead of 5% palladium / carbon. As a result, diphenyl carbonate was obtained with a yield of 5.35% with respect to phenol (3.48 mmol, palladium turnover number 1740). As by-products, phenyl salicylate was 0.57% to diphenyl carbonate, and 47.1% to tetrabutylammonium bromide used for bromophenol (total of ortho and para isomers, meta isomer not observed) ), Carbon dioxide was 0.38 mmol.

Example 21 The amount of 5% palladium / carbon used was 2.13 mg (1.
0 μmol Pd) and copper (II) acetate monohydrate 9.58 mg
The reaction was performed in the same manner as in Example 15 except that (0.048 mmol) was added. As a result, diphenyl carbonate was obtained in a yield of 4.15% with respect to phenol (2.70 mmol, palladium turnover number 2455). As a by-product, phenyl salicylate is 0.8 with respect to diphenyl carbonate.
6%, 10.8% based on tetrabutylammonium bromide used by bromophenol (total of ortho and para forms, meta form not observed), carbon dioxide 0.36
It was mmol.

Comparative Example 6 The reaction was performed in the same manner as in Example 15 except that 16.09 mg (0.048 mmol) of cerium (III) acetate monohydrate was used instead of lead (II) oxide. As a result, diphenyl carbonate was obtained in a yield of 2.01% with respect to phenol (1.30 mmol, palladium turnover number 690). As by-products, phenyl salicylate was 2.52% to diphenyl carbonate and 9.1% to tetrabutylammonium bromide used for bromophenol (total of ortho and para isomers, and meta isomer was (Not observed), carbon dioxide was 0.19 mmol.

[0034]

As is clear from the above results, in the catalyst system of the present invention, the turnover number of palladium can be greatly increased by reducing the amount of palladium used. Further, it is possible to reduce the amount of by-products that are difficult to separate by distillation. Therefore, the industrial value of the method of the present invention is extremely high.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Iwane 8-3-1 Chuo, Ami-cho, Inashiki-gun, Ibaraki Mitsubishi Chemical Corporation Tsukuba Research Center

Claims (14)

[Claims] 1. A method of producing an aromatic carbonic acid ester by reacting an aromatic hydroxy compound with carbon monoxide and oxygen, wherein in the reaction system, one or more selected from (A) palladium and a palladium compound, and (B) lead. An aromatic carbonic acid ester characterized by carrying out the reaction in the presence of at least one compound selected from compounds and at least one halide selected from (C) quaternary ammonium halides and quaternary phosphonium halides. Manufacturing method. 2. The method according to claim 1, wherein the (A) is palladium acetate or palladium / carbon. 3. The (B) is a lead oxide or Pb (O).
The method according to claim 1, which is a lead compound represented by R) ₂ [R represents an acyl group having an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms]. 4. The method according to claim 1, wherein the (C) is bromide. 5. The method according to claim 4, wherein the (C) is tetrabutylammonium bromide or tetraphenylphosphonium bromide. 6. The method according to claim 1, wherein the (A) is in a molar ratio within the range of 10 ⁻⁶ to 10 ⁻³ with respect to the aromatic hydroxy compound. 7. The method according to claim 1, wherein the (B) is in a molar ratio of 10 ⁻⁴ to 10 ⁻² with respect to the aromatic hydroxy compound. 8. The method according to claim 1, wherein the (C) has a molar ratio within the range of 10 ⁻³ to 10 ⁻¹ with respect to the aromatic hydroxy compound. 9. The method according to claim 1, wherein the (C) is selected from quaternary ammonium halides. 10. The method according to claim 9, further comprising one or more selected from (D) copper and a copper compound in the reaction system. 11. The method according to claim 10, wherein said (D) is selected from organic acid salts of copper, copper halides, copper oxides and metallic copper. 12. The method according to claim 10, wherein the (D) is in a molar ratio of 10 ⁻⁴ to 10 ⁻² with respect to the aromatic hydroxy compound. 13. The method according to claim 1, wherein the reaction temperature is in the range of 80 to 130 ° C. 14. The method according to claim 1, wherein the partial pressures of carbon monoxide and oxygen are 30 to 100 atm and 1 to 10 atm, respectively.