JPS60169441A - Production of cinnamic acid ester - Google Patents

Abstract

PURPOSE:To impart catalytic activity to used catalyst, easily, in the production of the titled compound by the reaction of styrene, a 1-4C aliphatic alcohol, carbon monoxide and oxygen in the presence of a specific catalyst, by separating and recovering the catalyst after the reaction, and heat-treating the catalyst together with an organic acid. CONSTITUTION:A cinnamic acid ester useful as a raw material of perfumery and agricultural chemicals is produced by reacting styrene with a 1-4C aliphatic alcohol, carbon monoxide and oxygen in the presence of a catalyst composed of (A) palladium metal or its compound, (B) a copper salt or iron salt and (C) an alkali metal or alkaline earth metal salt, wherein either B or C is a halide. After the reaction, the catalyst is separated and recovered from the reaction system, and heat-treated together with an organic acid, especially an aliphatic or aromatic carboxylic acid such as acetic acid, propionic acid, benzoic acid, etc. The catalytic activity can be imparted to the used catalyst, and the objective compound can be produced economically on an industrial scale.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing cinnamic acid esters. Specifically, the present invention relates to a method for producing cinnamic acid esters by oxidatively carbonylating styrenes in the presence of alcohol.

Cinnamic acid is cinnamaldehyde, cyclamenaldehyde, β-
Along with amyl cinnamaldehyde, it is not only used as a raw material for fragrances, but also as a raw material for agricultural chemicals.
On a laboratory scale, it is produced by the Perkin reaction or the condensation reaction of benzaldehyde and ketene.

As a method for producing cinnamic acid ester by oxidative carbonylation reaction of styrene, JP-A-16-/! Kodar is known, but this method uses (1) a platinum group metal or its compound, (2) a copper salt or an iron salt, and (3) an organic compound of a metal selected from alkali metals, alkaline earth metals, and aluminum group metals. A catalyst consisting of an acid salt is used. However, when this catalyst system is used continuously or repeatedly, its catalytic activity tends to gradually deactivate.

As a result of extensive research into methods for activating such catalyst systems, the present inventors have discovered that catalytic activity can be imparted to scales by an extremely simple method of treatment with an organic acid, and the present invention has been achieved. reached.

That is, the purpose of the present invention is to provide an industrially advantageous method for producing cinnamic acid esters by oxidative carbonylation reaction, and the purpose is to provide styrenes, the number of carbon atoms/-4Z, according to the present invention. Aliphatic alcohols, - carbon and oxygen oxides, such as (a) palladium metal or its compounds, (cut copper salts or iron salts and () alkali metal or alkaline earth metal salts), and (b) and ( In the method of producing cinnamic acid esters by reacting the salts in c) in the presence of a catalyst in which one of the salts is a halide, the catalyst separated and recovered after the reaction is heat-treated with an organic acid. achieved.

The present invention will be explained in detail below.

The raw material used in the method of the present invention has the general formula (wherein R1 represents hydrogen, halogen, an alkyl group having 1 to 2 carbon atoms, or an alkoxy group having 1 to 1 carbon atoms, and R1 represents hydrogen or a carbon atom. styrenes, aliphatic alcohols having 1-d carbon atoms, -carbon oxide, and oxygen.

Specific examples of the styrenes include styrene, β-methylstyrene, p-methylstyrene, p-methoxystyrene, p-chlorostyrene, β-methyl-p-isopropylstyrene, and β-amylstyrene.

Specific examples of aliphatic alcohols having a carbon atom number of -4' include methanol, ethanol, isopropyl alcohol, n-butyl alcohol, and -butyl alcohol, but acetals, ketals, orthoesters of carboxylic acids, di-butyl alcohols, etc. Compounds that can be dissociated in the reaction system to release the above-mentioned alcohol, such as alkoxycycloalkanes and orthoboric acid esters, can also be used.

- Carbon oxide and oxygen can be used in a pure state, but they can also be used diluted with an inert gas such as nitrogen or argon.

The reaction according to the method of the invention involves (a) palladium metal or a compound thereof, (b) a salt of copper or iron, and (a) a salt of an alkali metal or alkaline earth metal;
) and (0) in the presence of a catalyst in which either one of the salts is a halogenide.

Examples of palladium include palladium black, metal palladium such as supported metal palladium, zero-valent palladium complexes such as tetrakis(triphenylphosphine) palladium, inorganic salts of covalent palladium such as palladium chloride and palladium nitrate, palladium acetate, and benzoic acid. Examples include carboxylates of covalent palladium such as palladium, and tetravalent palladium complexes such as bis(acetylacetonato)palladium and bis(triphenylphosphine)dichloropalladium. When using palladium supported on a carrier, silica, alumina, silica alumina, magnesia, titania, diatomaceous earth, activated carbon, graphite, barium carbonate, calcium carbonate, etc. are used as the carrier.

Salts of copper or iron include their organic acid salts, namely acetates, propionates, butyrates, stearates,
Examples include benzoate, but acetate is particularly effective. Examples of the copper or iron halide include cupric chloride and ferric bromide.

Examples of halides of alkali metals or alkaline earth metals include lytecum chloride, sodium chloride, cacium chloride, barium chloride, barium bromide, barium iodide, etc. Typical examples of these organic acid salts include , the acetate is opened.

The ratio of these three components used as a catalyst is such that the atomic ratio of palladium metal or its compound to copper or iron salt is //
pair/~z o o, o, preferably l vs. 1o-
It is appropriate to use it within the range of zoo.

The molar ratio of the copper or iron salt and the alkali metal or alkaline earth metal salt is in the range of l to 0.0/~too, preferably l to o, 1-io. It is appropriate to use.

However, as the reaction progresses, the catalytic activity of catalysts composed of such components tends to decrease slightly, but this is due to the water produced during the reaction, which causes the oxidation of copper or iron, for example. It is presumed that this is due to the fact that salts and the like weaken certain functions through reactions such as hydrolysis. In order to prevent such a decrease in activity, it is necessary to heat-treat the catalyst separated and obtained after the completion of the reaction together with an organic acid according to the method of the present invention.

The organic acids used include carboxylic acids, especially aliphatic or aromatic carboxylic acids such as acetic acid, propionic acid, benzoic acid.

The amount of organic acid used is the molar ratio of copper or iron salt to organic acid: 0.7-! 00. It is preferable to use the organic acid in a ratio of 1 to 1 to SO, but in order to facilitate the treatment operation, a larger amount of organic acid can be added to the treatment. The treatment with an organic acid consists of heating the separated and recovered catalyst together with the organic acid.

The heat treatment method is preferably carried out as follows. First, the catalyst is separated from the reaction system by filtration or drying, and then acetic acid is added and heated at 30C to JO'C, preferably around the boiling point of acetic acid, for 10 minutes to several hours. . After heating, the acetic acid is removed and the catalyst can be used again for the reaction, but it is not necessary to completely remove the acetic acid. In order to efficiently separate the catalyst component from the reaction system, it is carried out in several stages, such as filtration in the first stage, followed by evaporation of the liquid phase containing raw copper or iron components to recover the solid components. You can also do that.

This procedure can be carried out in an optimal manner in conjunction with the product separation method described below.

In carrying out the method of the present invention, there is no problem even if no reaction solvent is used, but in some cases, an appropriate inert solvent may be used to facilitate the operation. Examples of such solvents include ethers such as diethyl ether, diphenyl ether, dioxane, tetrahydro7rane, ethylene glycol dimethyl ether, acetone, methyl ethyl ketone, dibutyl ketone,
Ketones such as acetophenone, esters such as methyl acetate, ethyl acetate, ethyl propionate, benzyl benzoate, dimethyl phenylconolate, aromatic hydrocarbons such as benzene, toluene, p-xylene, ethylbenzene, etc. - Aliphatic or alicyclic hydrocarbons such as hexane, n-octane, cyclohexane, acetamide, N-
Examples include amides such as methylpyrrolidone and carbonates such as ethylene carbonate and propylene carbonate.

This reaction can be carried out either batchwise or continuously, and the catalyst separation and recovery method can be easily converted into a process by adopting means suitable for each reaction method. I can do it.

Regarding the selection of the reaction temperature, in the method of the present invention, the yield of cinnamic acid esters can be improved by increasing the reaction temperature, but if it is too high, side reactions such as the production of carbon dioxide may occur. On the other hand, since the selectivity of cinnamic acid esters decreases, the reaction temperature is usually within the range of room temperature to 200 C1, preferably 40 C1/AOC.

For the reaction product liquid obtained by carrying out the method of the present invention,
By employing conventional separation means such as distillation and extraction,
Cinnamate esters can be separated and obtained.

Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples which do not go beyond the gist of the invention.

In addition, in the examples, the selectivity of methyl cinnamate has the following meaning.

Example / Internal volume with magnetic induction rotary stirrer, reflux condenser, gas inlet tube, liquid withdrawal tube, ? 00yd Teflon inner cylinder Hastelloy C autoclave & % P6/A, C
, (3% by weight of palladium supported on activated carbon) as Pd. ! ; mmot, cupric acetate! ;, Om
moj, barium chloride! ;, Ommot.

Filled with 70ml of styrene and 301nl of methanol,
Nitrogen/oxygen/-carbon oxide mixture gas (ZAJ/!;
, k/7,? (capacity ratio of
While flowing the mixed gas at /br, the reaction temperature was increased to 100%.
The reaction was carried out for 3 hours while maintaining the temperature at C. In this system, methyl cinnamate was increased by 9 mmot and carbon dioxide was increased by 7 mmolmm. On the other hand, the selectivity of methyl cinnamate is 3. It was a lot of fun. The catalyst-containing reaction solution (representing a heterogeneous phase) taken out from the autoclave was allowed to stand at room temperature for several hours, and then filtered under suction to recover solid catalyst components separately. The weight of this solid catalyst component after drying at TOC for a day and night was λ, 3 tons.

The solid catalyst component thus obtained corresponds to the sufficient weight of O, CO! Soak the tuna in three glasses of acetic acid and place it in a flask! , and heated at 25C for 1 hour to completely evaporate acetic acid. The weight of the acetic acid-treated solid catalyst component thus obtained was 17 tons. The entire amount of this solid, along with 7 styrene and 3 methanol, was charged into a spinner-stirred glass inner cylinder autoclave made of Steroid C having an internal capacity of 1 ml, and after sealing, 7 g of carbon oxide and 3 oz/aiG were pressurized into the autoclave. Next, 6% OH/kJ1 gas was injected, and the total pressure was 10 at room temperature. ; kg/cr/IG. The autoclave was heated in an electric furnace and kept at 0C to carry out a reaction for 30 minutes.

What about the resulting methyl cinnamate? ,J? mmoz
.

Methyl cinnamate selectivity is 7 with carbon dioxide /, / J mmot,,! It was 1-4'%.

Example internal volume? θN's spinner stirring type glass inner cylinder tsuta steroid cl! Add styrene d1 methanol 31111%-%Pd/A, C, to P (1, 0
．． 0 k mmot, cupric chloride 0. r mmot and barium acetate Oj mmot were charged and sealed, -carbon oxide g and OH/cr/lG were press-fitted. Then 6chi0. /N
Press in the cylinder and bring the total pressure to /θJ ky /cy! at room temperature. It was set as a.

First, perform the reaction for 30 minutes with COC and methyl cinnamate? ,
/ / mmot, carbon dioxide λj o mrnot was obtained. The selectivity of methyl cinnamate was 67%.

The entire amount of the reaction solution containing the catalyst thus obtained was first filtered at room temperature. The solid catalyst components were distributed door to door! Dry edge with OC 0.
The entire amount was immersed in 2rILl of acetic acid and heated in a flask at 1lsc for 7 hours to completely evaporate the acetic acid. The acetic acid-treated solid catalyst component thus obtained had a weight of O. datilt. The entire amount of this solid was charged again into the same autoclave with an internal volume of 90 ml together with 7M styrene and 3-methanol, and the reaction was carried out under exactly the same reaction conditions. The resulting methyl cinnamate was 9,
The selectivity for carbon oxide was 42 mmoA and methyl cinnamate was 43 mmoA.

Comparative Example 1 O,CoSat among the solid catalyst components obtained in Example// was introduced into a 90 ml autoclave together with styrene 7d and methanol 3- without being treated with acetic acid under the same conditions as Example/. When the reaction was carried out,
The amount of methyl cinnamate produced is θ, 0! mmot, there is no carbon dioxide production, and the selectivity for methyl cinnamate is as, t
It was o%.

Comparative Example and Example C. Reaction, separation, and analysis were carried out under exactly the same conditions as in Example C, except that the heat treatment with acetic acid was not performed.

The production of methyl cinnamate was 0. ; l 3 mmot, the production of carbon dioxide is 0. / mmot, the selectivity of methyl cinnamate is 23. It was 3%.

Sender: Mitsubishi Chemical Industries, Ltd. Representative Patent Attorney Hase - (1 person)

Claims (1)

[Claims] (1) Styrenes, aliphatic alcohols with a carbon atom number/~Hiroshi, -carbon oxides and oxygen (a) radium metal or its compounds, (b) copper salts or iron salts, and (C) alkali metals or alkalis. Salts of earth metals, and (
In the method for producing cinnamic acid esters by reacting the salts b) and (C) in the presence of a catalyst in which either one is a halide, the catalyst separated and recovered after the reaction is heat-treated with an organic acid. A method for producing cinnamic acid esters, characterized by: