JPS61246148A - Production of cinnamic esters - Google Patents

Abstract

PURPOSE:In the production of the title substance used as a raw material for perfumes by reaction between styrene, carbon monoxide, an alcohol and oxygen, the copper content and the ratio of the copper to chlorine are specified in the cocatalyst which is composed of three constituents to increase the activity of the main catalyst and the yield of the product. CONSTITUTION:In the reaction between styrene, carbonmonoxide, alcohol and oxygen in the presence of a major catalyst metallic palladiumor its compound and a cocatalyst of (i) a copper organic acid salt, (ii) a chlorine compound and (iii) a manganese or zinc compound, the amount of copper atom is set to 0.004-0.4g.atom/l, preferably 0.008-0.3g.atom./l, the gram-atomic ratio of chlorine atoms to copper atoms is set to less than 2, preferably 0.02-1.99 and the reaction is carried out at normal pressure to 500kg/cm<2>G, preferably at normal pressure to 300kg/cm<2> at 40-160 deg.C to give the objective compound.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing cinnamic acid esters by reacting styrenes, carbon monoxide, alcohol and oxygen.

Cinnamic acid esters are widely used as fragrances or raw materials thereof due to their aromatic properties, and are also important compounds as raw materials for agricultural chemicals and photosensitive resins.

(Prior Art) Cinnamic acid has conventionally been produced on a small scale by a reaction using benzaldehyde and acetic acid derivatives as main raw materials.

However, since this method uses expensive raw materials, it is not an industrially preferred method. As a method using cheaper raw materials, several methods have been proposed in which cinnamic acid esters are produced by reacting styrenes with carbon monoxide, alcohol, and oxygen in the presence of a catalyst (for example, 1983-70836, Japanese Patent Publication No. 56-7103
9, JP-A-56-15242, etc.).

(Problems to be Solved by the Invention) However, none of these methods has achieved industrially satisfactory reaction results and catalytic activity.

The purpose of the present invention is to provide a more advantageous industrial production method for cinnamic acid esters using styrenes, carbon monoxide, alcohol, and oxygen as raw materials, specifically to develop the activity of the main catalyst to a high degree and achieve high reaction results. An object of the present invention is to provide a method for producing cinnamic acid esters.

(Means for Solving the Problem) In order to achieve the above object, the inventors of the present invention have continued to conduct intensive studies and found that the conventional techniques, for example,
As shown in the examples of Patent No. 836 and No. 56-15242, when only cupric chloride is used as the cocatalyst copper salt, the amount of copper atoms used should be selected within a preferable range. If so, the amount of chlorine atoms to be used is limited by this, and a preferable range cannot be arbitrarily selected, and it was discovered that this is one of the reasons why the catalyst system is not industrially satisfactory. As a result of further investigation, it was found that styrenes, monomers, etc. were used in the presence of palladium metal or its compound as the main catalyst, an organic acid salt of copper as a co-catalyst, (2) a chlorine compound, and (3) a manganese or zinc compound. When producing the corresponding cinnamic acid esters by reacting carbon oxide, alcohol, and oxygen, the amount of copper atoms per liter of reaction mixture is set in a specific range, and the gram atomic ratio of chlorine atoms to copper atoms is specified. The inventors have discovered that by adjusting the amount within this range, high activity of the main catalyst can be obtained and cinnamic acid esters can be produced with high reaction results, and the present invention has been achieved.

In the present invention, in the presence of palladium metal or its compound as a main catalyst, an organic acid salt of copper as a promoter, (2) a chlorine compound, and (3) a manganese or zinc compound, and oxygen to produce the corresponding cinnamic acid esters, the amount of copper atoms in the reaction mixture is 0.004 to 0.4 g atom/
This is a method for producing cinnamic acid esters, which is characterized in that the reaction is carried out with the gram atomic ratio of chlorine atoms to copper atoms being less than 2.

Styrenes used in the method of the present invention include:
Specifically, styrene, α-methylstyrene, β-methylstyrene, α-ethylstyrene, β-ethylstyrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, m-ethylstyrene, p-ethyl Styrene, p-tert-butylstyrene, β-methyl-p-
Alkyl derivatives of styrene such as inpropylstyrene,
Or p-chlorostyrene, p-methoxystyrene,
Examples include styrene derivatives having a substituent on the aromatic ring that does not inhibit the reaction, such as 3.4-dimethoxystyrene.

Alcohols include methanol, ethanol, propatool, butanol, pentanol, octatool, cyclohexanol, cyclohexanol, phenol,
These are alcohols such as benzyl alcohol, ethylene glycol, polyethylene glycol, and propylene gelicol, and they may have a substituent such as a halogen or an alkoxy group that does not inhibit the reaction. The amount of these alcohols used is 1 to 100 per mole of styrene.
It is expressed in molar parts and can be used not only as a reaction raw material but also as a solvent.

The partial pressure of carbon monoxide is normal pressure to 50 kNdG, and if the partial pressure is higher than this, the corresponding by-products of phenylsuccinic acid diesters will increase. More preferably normal pressure to 40k
g/cdG.

The partial pressure of oxygen is normal pressure ~ 50 kg/cr! , and the partial pressure is high (then by-products increase. More preferably normal pressure to 3
0 to 9/crIG. The oxygen source may be pure oxygen or air.

In order to avoid an explosive range, it is preferable to use the mixed gas of carbon monoxide and oxygen diluted with an inert gas such as nitrogen or argon.

The required amount of the mixed gas of carbon monoxide, oxygen, and inert gas may be charged into the reactor all at once, or may be added intermittently. Further, a method of constantly circulating or a method of distributing intermittently may be used.

In the reaction according to the method of the present invention, the alcohol as a raw material can essentially be used as a solvent, but any solvent can also be used as long as it does not inhibit the reaction. Examples of such solvents include ethers such as diethyl ether, dipropyl ether, methyl ethyl ether, phenylethyl ether, diphenyl ether, tetrahydrofuran, dioxane, ethylene glycol diethyl ether, and tetraethylene glycol dimethyl ether, acetone, methyl ethyl ketone, acetophenone, etc. ketones, esters such as methyl acetate, ethyl acetate, and methyl propionate, aromatic hydrocarbons such as benzene, toluene, p-xylene, ethylbenzene, chlorobenzene, and dichlorobenzene, or their substituted compounds, n-hexane, n- Aliphatic or alicyclic hydrocarbons such as pentane and cyclohexane, propylene carbonate; carbonates such as dimethyl carbonate, nitriles such as acetonitrile and benzonitrile, nitro compounds such as nitrobenzene and nitromethane, and amide compounds such as dimethylformamide. and sulfone compounds such as sulfolane.

The main catalyst of the present invention, palladium metal or its compound, includes palladium black, metal palladium supported on a carrier such as activated carbon, asbestos, or silica alumina, and zero-valent palladium complexes such as dibenzylidene acetone complex. palladium metal or compounds, palladium chloride, inorganic acid salts of palladium such as palladium nitrate, organic acid salts of palladium such as palladium acetate or palladium benzoate, palladium bis(acetylacetonato), cyclooctadiene dichloropalladium, palladium chloride benzonitrile Examples include divalent palladium compounds such as palladium complexes, palladium chloride pyridine complexes, palladium chloride ammine complexes, and the like.

The amount of palladium metal or its compound used is in the range of 0.00001 to 0.1 gram atom, preferably 0.00005 to 0.01 gram atom, per mole of styrene as a raw material. be.

The cocatalysts used in the method of the present invention are: (1) an organic acid salt of copper, (2) a chlorine compound, and (2) a compound of manganese or zinc. The first component, organic acid salts of copper, include copper aliphatic carboxylates such as copper acetate, copper propionate, and copper stearate, aromatic copper carboxylates such as copper benzoate, and copper acetylacetonate. Examples include salts of organic anions of copper such as .

These organic acid salts of copper can be used alone or in combination of two or more. Further, it is preferable that these organic acid salts of copper be dissolved in the reaction mixture, but a portion of them may remain insoluble as N. The amount of these organic acid salts of copper used is 0.004 to 0.4 gram atoms per liter of reaction mixture as copper atoms. However, when copper chloride is used as the chlorine compound (1), which is a cocatalyst, the copper atom of this compound is also included in the above range and an organic acid salt of copper is used. If the amount of copper is less than this range (the reaction will hardly occur, if it is more than this range the amount of by-products will increase), more preferably between o,oos and 0.3 gram atoms per liter of reaction mixture. be.

The chlorine compound which is the second component of the co-catalyst includes chlorine or its solution, hydrogen chloride or its solution, amine hydrochloride, and also tert-butyl chloride, phosgene, phosphorus pentachloride, phosphorus oxytrichloride, etc. Examples include chlorine-containing compounds that tend to generate chlorine ions, or chlorides or oxychlorides of metals such as titanium, vanadium, manganese, iron, copper, zinc, or aluminum depending on their valences. These chlorine compounds may be used alone or in combination.
A mixture of more than one species may be used. These chlorine compounds are used in an amount of less than 2, ie, more than O and less than 2, in terms of the ratio of chlorine atoms to copper atoms present in the reaction mixture. However, when palladium chloride is used as the main catalyst, the amount is usually in a trace amount, but the amount is within the range including the chlorine atoms from palladium chloride. When the ratio of chlorine atoms to copper atoms is 0, that is, when no chlorine atoms are present, almost no reaction occurs. When this ratio increases to 2 or more, by-products increase and the selectivity and yield of cinnamic acid esters decrease. Preferably 0.02 to 1.99
Gram atomic ratio.

The manganese or zinc compound which is the third component of the cocatalyst in the method of the present invention may be manganese or zinc chloride, acetate, propionate, or salt of aliphatic carboxylic acid such as stearate, or benzoate. Examples include salts of aromatic carboxylic acids such as acid salts, and salts of organic anions such as acetylacetonate.

It is preferable that these compounds be dissolved in the reaction mixture, but there is no problem even if some of them are insoluble.

The amount of these manganese or zinc compounds to be used is such that the ratio of manganese or zinc metal atoms to copper atoms present in the reaction mixture is from 0.05 to 50, more preferably from 0.1 to 10. Two or more kinds of manganese or zinc compounds can also be used at the same time.

The manganese or zinc chloride can simultaneously satisfy the chlorine compound as the second component of the cocatalyst and the manganese or zinc compound as the third component.

The total pressure of the reaction according to the method of the present invention is from normal pressure to 500 kg/
crlG, preferably normal pressure to 300k11/cII
tG, and the reaction temperature is room temperature to 200°C, preferably 40 to 160°C. The reaction time varies depending on the reaction conditions, but is usually 0.01 to 24 hours, preferably 0.05 hours.
~lO hours. After the reaction is completed, the cinnamic acid esters can be separated from the reaction product liquid by a commonly used separation method such as distillation or extraction.

(Actions and Effects of the Invention) According to the method of the present invention, a preferable range of the amount of copper atoms serving as a cocatalyst and a preferable range of the ratio of chlorine atoms to copper atoms can be given to the reaction system, and the reaction can be carried out within these ranges. This makes it possible to produce cinnamic acid esters with surprisingly high reaction results using an extremely small amount of palladium main catalyst, resulting in an industrially extremely advantageous method for producing cinnamic acid esters.

(Example) Next, the method of the present invention will be explained in more detail by showing Examples and Comparative Examples.

Example 1 In a glass cylindrical container, 11.23 milligrams (0,050 mmol) of palladium acetate and cupric acetate monohydrate 2
．． 50 g (12.5 mmol) and 3.82 g (15.6 mmol) of manganese acetate tetrahydrate were weighed out, and a small amount of methanol was added thereto, and 26.
Weigh out 4 grams (250.0 mmol) of hydrogen chloride gas and add a solution (concentration 0.5-2N) in which hydrogen chloride gas was absorbed into methanol, the concentration of which had been measured just beforehand, until the amount of hydrogen chloride was 6. The total amount was adjusted to 25 mmol, and methanol was further added to bring the total amount to 125 d.

The amount of copper atoms per liter of reaction mixture is 0.10 gram atoms, and the gram atomic ratio of chlorine atoms to copper thickness is 0.50. This glass container was placed in a 500 m/autoclave. The autoclave's stirring blades are made of glass, and the temperature measuring tube is also protected by glass.

A mixed gas with a partial pressure ratio of carbon monoxide:oxygen:nitrogen of 10:5:85 was introduced into the autoclave at a total pressure of 50 Kg+/crl G at a rate of 1.2 t/min (standard condition) at the outlet while stirring was continued. The reaction was carried out at ℃ for 3 hours.

During this time, the outlet gas was discharged through a reflux condenser.

After the reaction was completed, it was cooled and depressurized, and the reaction solution taken out was analyzed by liquid chromatography, and the amount of styrene was 12.25.
2178 mmol of methyl cinnamate) 825 mmol of dimethyl phenylsuccinate, which was a by-product, was contained. Styrene conversion rate: 95.1%, methyl cinnamate selectivity (yield based on consumed styrene): 91.6%
, yield of methyl cinnamate (yield based on charged styrene)
was 87.1%, the selectivity for dimethyl phenylsuccinate was 3.5%, and the yield was 3.3%. The number of moles of cinnamic acid ester produced per gram atom of palladium of the main catalyst (hereinafter abbreviated as Pd turnover) was 466°.

Example 2 7 milligrams (o, oso mmol) of palladium chloride BB, 2.19 grams (10,97 mmol) of cupric acetate monohydrate, 0.206 grams (1,53 mmol) of cupric acetate and 382 grams of monomanganese tetrahydrate salt (
After adding some methanol, 26.04 g (250.0 mmol) of styrene was added, and methanol was further added to bring the total amount to 125 mA'. The total amount of copper atoms per reaction mixture 1 is 0.10 gram atoms, and the gram atomic ratio of total chlorine atoms to total copper atoms is 0.25. When the reaction was carried out in the same manner as in Example 1, the conversion of styrene was 943%, and the selectivity and yield of methyl cinnamate were 92% and 87.5%, respectively.
It was Chi. The Pd rotation rate was 4680. less than,
The comparative examples and examples show the range of the amount of copper atoms per reaction mixture 1.

Comparative Examples 1 and 2, Examples 3.4 and 5 All the same as Example 2 except that the amounts of cupric acetate monohydrate and cupric chloride used in Example 2 were changed to the amounts shown in Table 1. The reaction was carried out in the same manner.

The ratio of chlorine atoms to copper atoms is all 1.0.

The results are shown in Table 1.

Next, the range of the gram atomic ratio of chlorine atoms to copper atoms will be shown based on comparative examples and examples.

Comparative Example 3.4 and Examples 6 to 9 All the same procedures as in Example 2 were carried out except that the amounts of cupric acetate monohydrate and cupric chloride and the type of palladium compound were changed as shown in Table 2. The reaction was carried out in the same manner as in Example 2.

The amount of copper atoms per liter of reaction mixture is all 0.1 gram atoms. The results are shown in Table 2 together with the results of Examples 2 and 4 mentioned above.

Example 10 5% Pd/C instead of palladium chloride in Example 2
Using 180 m9 (0.085 milligram atom of palladium) of 5% by weight of palladium supported on activated carbon, 1.89 g (9 g of cupric acetate monohydrate) was used.
, 47 mmol) and 419 mg (3
. The amount of copper atoms per liter of reaction mixture is 0
．． 1 gram atom, and the ratio of chlorine atoms to copper atoms is 0.50.

The styrene conversion rate was 86.4%, the methyl cinnamate selectivity was 79.6%, and the recovery rate was 68.8%.

Example 11 Everything was the same as in Example 2 except that parachlorostyrene was used in place of styrene, ethanol was used in place of methanol, and the amount of palladium chloride was changed to 0.1 mmol. Ethyl 4-chlorocinnamate was produced in a yield of 602%.

Example 12 The amount of palladium acetate in Example 1 was changed to 9.0 milligrams (0.04 millimoles), and instead of hydrogen chloride gas, a liquid obtained by absorbing chlorine gas in methanol was used, and the amount of chlorine atoms was 6.26 milligrams. It was made to be atomic, and everything else was the same as in Example 1. There are 0.10 gram atoms of copper per liter of reaction mixture, and the gram atomic ratio of chlorine atoms to copper atoms is 0.50.

Styrene conversion rate 94.8%, methyl cinnamate selectivity 8
The recovery rate was 2.3%, and the recovery rate was 78.0%. Pd rotation rate is 4
It is 880.

Examples 13 to 17 The palladium compounds shown in Table 3 were mixed at 0.04 mi! The reaction was carried out in the same manner as in Example 2, except that 7 mol was used and the types and amounts of each cocatalyst component were changed as shown in Table 3.

The results are shown in Table 3 below those of Example 12.

Procedural amendment (@ (transfer) July 1985 IC Director General Michibe Uga 1, Indication of the case 1985 Patent Application No. 85508 2, Name of the invention Process for producing cinnamic acid esters 3, Person making the amendment 4: Columns 1) "Claims" and "Detailed Description of the Invention" of the specification subject to amendment 1) Amend the "Claims" of the specification as shown in the attached sheet.

2) Similarly, on page 3, lines 13 to 18, change ``When producing palladium metal as the main catalyst...'' to [using palladium metal or its compound as the main catalyst, carbon monoxide, alcohol, and oxygen]. Copper and chlorine are important as cocatalysts in the reaction to produce the corresponding cinnamic acid esters, and their sources are each a separate compound.

or, at least in part, as separate compounds, the amounts of each of which must be selected within a specific range, i.e. palladium metal or its compound as the main catalyst and an organic acid salt of copper as a co-catalyst.

(2) using a chlorine compound and (3) a compound of manganese or zinc.''

3) Similarly, on page 4, lines 4 to 9, "In the production of palladium metal as the main catalyst, the present invention uses styrenes and carbon monoxide."

When producing the corresponding cinnamic acid esters by reacting alcohol and oxygen, palladium metal or its compound is used as the main catalyst, and (1) an organic acid salt of steel, (2) a chlorine compound, and (3) as a co-catalyst. using manganese or zinc compounds.''

4) Similarly, the following Examples 18 to 20 are added after page 20.

2.50 grams monohydrate (12.5 mmol) in cupric acetate, 3.82 grams manganous acetate tetrahydrate (15,
After adding a small amount of methanol to this, take 26.04 grams (250.0 mmol) of styrene, and add 1 [hydrogen chloride gas whose concentration had been measured beforehand] to methanol. 6. The absorbed liquid (concentration 1.07N) - was added so that the amount of hydrogen chloride was 6.4 mmol, and methanol was further added so that the total amount was 125 d.

The amount of copper atoms per liter of reaction mixture is 0.10 gram atoms, and the total gram atomic ratio of chlorine atoms to copper atoms is 0.52. The same reactor as in Example 1 was used, except that the total pressure was 35 kg/dG and a mixed gas with a carbon monoxide:oxygen:nitrogen partial pressure ratio of 9.9:5.1:85.0 was used. The reaction was carried out in the same manner as in Example 1.

The conversion rate of styrene was 93.7%, the yield and selectivity of methyl cinnamate were 89.1% and 83.5%, respectively, and the Pd turnover rate was 4180.

Example 19 A solution in which water chloride and hydrogen gas were absorbed into methanol (concentration 1.
11N) was added and the amount of hydrogen chloride was 6.7
All preparations were the same as in Example 18, except that the amount was adjusted to millimoles. The amount of copper atoms per liter of reaction mixture remains unchanged at 0.10 gram atoms, and the total gram atomic ratio of chlorine atoms to copper atoms is 0.54. Using the same reactor as in Example 1, the total pressure was set to 35 #/dG and the partial pressure ratio of carbon monoxide:oxygen:nitrogen was 8.9:5.5.
: All Example 1 except that a mixed gas of 85.6 was used.
reacted in the same way.

The conversion of styrene was 94.2%, and the selectivity and yield of methyl cinnamate were 91.3% and 86.0%, respectively.
%Met. The Pd rotation rate was 4300.

Example 20 Liquid in which hydrogen chloride gas was absorbed into methanol (concentration 1.0
7N) to 5. - In addition, all the preparations were the same as in Example 18, except that the amount of hydrogen chloride was 5.4 mmol.

The amount of copper atoms per liter of reaction mixture remains unchanged at 0.1
The gram atomic ratio of 1 total chlorine atom to copper atom is 0.44.

Using the same reactor as in Example 1, the total pressure was 20 Yu/dG, and the partial pressure ratio of carbon monoxide:oxygen:nitrogen was 8.9:5.
．． The reaction was carried out in the same manner as in Example 1 except that a mixed gas of 5:85.6 was used. Styrene conversion rate 89
．． 3%, selectivity and yield of methyl cinnamate were 9, respectively.
0.5% and 80.8%.

The Pd rotation rate was 4040. ” Above, the appendix “Claims: A metal or its compound, and an organic acid salt of copper as a promoter (2) a chlorine compound and (3) a manganese or zinc compound are used to reduce copper atoms in one reactor mixture to 0. .004
~0.4 gram atom/l.

A method for producing cinnamic acid esters, characterized in that the reaction is carried out at a gram atomic ratio of chlorine atoms to copper atoms of less than 2. ” Procedural amendment stamp button April 4, 1986

Claims (1)

[Claims] 1) In the presence of palladium metal or its compound as a main catalyst, and an organic acid salt of copper as a co-catalyst, (2) a chlorine compound and (3) a compound of manganese or zinc,
When producing the corresponding cinnamic acid esters by reacting styrenes, carbon monoxide, alcohol and oxygen,
A method for producing cinnamic acid esters, characterized in that the reaction is carried out with the copper atoms in the reaction mixture being 0.004 to 0.4 gram atom/l and the chlorine atom to copper atom ratio being less than 2.