JPH0910596A - Catalyst for oxidative dehydrogenation reaction and preparation of alpha,beta-unsaturated carbonyl compound - Google Patents

Abstract

PURPOSE: To obtain an α,β-unsaturated carbonyl compound at a high yield in safe, mild conditions by using a catalyst which is prepared from a suspended compound obtained by reacting a nitrogen-containing compound or an acetic acid compound with palladium carboxyl acetate. CONSTITUTION: A catalyst for producing an α,β-unsaturated carbonyl compounds by the oxidative dehydrogenation of allyl alcohols which is prepared from a suspended compound obtained by reacting a nitrogen-containing compound or an acetic acid compound with palladium carboxyl acetate obtained by the reaction in which palladium acetate is reacted with carbon monoxide in acetic acid. The nitrogen-containing compound is 1,10-phenanthroline, 2,2-bipyridine, or triethylamine and is a pyridine compound expressed by the formula, in which R<1> , R<2> are the same or different and indicate hydrogen atom or 1-8 C alkyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a catalyst for producing α, β-unsaturated carbonyl compounds by oxidative dehydrogenation of allyl alcohols, and allyl alcohols in an oxygen atmosphere in the presence of the catalyst. Oxidative dehydrogenation reaction at α,
It relates to a method for producing β-unsaturated carbonyl compounds.

[0002]

2. Description of the Related Art α, β-Unsaturated carbonyl compounds are useful substances used for various industrial chemicals such as fragrances and pharmaceuticals and their synthetic intermediates.

Conventionally, as a method for producing such α, β-unsaturated carbonyl compounds, for example, a method of oxidizing allyl alcohols with an oxidizing agent such as active manganese dioxide or hexavalent chromic acid has long been known. ing. However, since these oxidation reactions are stoichiometric reactions and a toxic heavy metal is used as an oxidizing agent, there is a problem in handleability.

It is also conceivable to apply an oxidative dehydrogenation reaction for producing carbonyl compounds by extracting hydrogen from alcohols to allyl alcohols to produce α, β-unsaturated carbonyl compounds. For example, in general, as a method for producing carbonyl compounds from alcohols, alcohols vaporized with steam at high temperature in a reactor filled with a copper catalyst, a zinc catalyst, etc.
A method of circulating and conducting an oxidative dehydrogenation reaction is known (for example, JP-A-51-16643 and JP-A-51-1).
3748, etc.). However, these gas phase reactions need to be carried out under high temperature reaction conditions, and when applied to allyl alcohols having unsaturated bonds, many decomposition side reactions occur, and it cannot be said to be an efficient reaction. Further, a method has been disclosed in which ruthenium is used as a catalyst in a liquid phase and hypochlorous acid is added dropwise to carry out an oxidative dehydrogenation reaction of alcohols (for example, JP-A-64-50836 and JP-A-63-63). 17494
No. 6, JP-A-63-145248, JP-A-SHO-6
3-130552, JP-A-62-265244, JP-A-56-22758 and the like). However, in such a liquid phase reaction, expensive hypochlorous acid must be used, and further, there is a disadvantage in that hypochlorous acid is unstable because of its instability.

Recently, a method using iridium triphenylphosphine as a catalyst for producing α, β-unsaturated carbonyl compounds by oxidative dehydrogenation of allyl alcohols has been reported (Journa).
l of Organometallic Chemi
story, 356, 381-8 (1988)). However, such organic iridium has a risk of explosion and has a large manufacturing disadvantage. A method using hexadecacarbonyl hexarhodium as a catalyst for oxidative dehydrogenation reaction (Japanese Patent Laid-Open No. 3-93742) is also known.
The use of expensive rhodium compounds is disadvantageous in that the catalyst is a homogeneous system and separation and reuse are difficult. Further, a method of using ruthenium oxide as a catalyst for oxidative dehydrogenation reaction (Journal of Organic Chemi)
Stry, Vol. 49, p. 3435-6 (1984)) is also known, but it is disadvantageous in handling because of the toxicity of ruthenium oxide. Further, a method of carrying out an oxidative dehydrogenation reaction of cinnamyl alcohol using a catalyst in which bismuth-platinum is supported on alumina (Journal of Catalysts).
is, 131, 131 (1995)), but it is disadvantageous for industrial production because of the toxicity of bismuth and the expensiveness of platinum.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a method for producing α, β-unsaturated carbonyl compounds from allyl alcohols under safe and mild reaction conditions without using an expensive oxidizing agent. The purpose is to do.

[0007]

Means for Solving the Problems In order to solve the above-mentioned problems of the prior art, the present inventors have conducted extensive studies on a catalyst used in an oxidative dehydrogenation reaction. As a result, they have found that the specific palladium compound shown below has high activity as a catalyst for producing α, β-unsaturated carbonyl compounds by oxidative dehydrogenation of allyl alcohols, thus completing the present invention. Came to.

That is, the present invention provides allyl alcohols consisting of a suspension compound obtained by reacting a palladium carboxylate acetate obtained by reacting palladium acetate with carbon monoxide in acetic acid with a nitrogen-containing compound or an acetic acid compound. Catalyst for producing α, β-unsaturated carbonyl compounds by oxidative dehydrogenation reaction, palladium carboxylacetate obtained by reacting palladium acetate with carbon monoxide in acetic acid is reacted with nitrogen-containing compound or acetic acid compound The resulting suspension compound is subjected to oxidative dehydrogenation reaction of a precipitate obtained by further adding an aromatic solvent and a step of contacting with oxygen, and allyl alcohols composed of the precipitate to obtain α, β- A catalyst for producing unsaturated carbonyl compounds, and allyl alcohols in the presence of the catalyst. α characterized by oxidative dehydrogenation reaction under hydrogen atmosphere, a process for producing β- unsaturated carbonyl compounds.

The catalyst for producing α, β-unsaturated carbonyl compounds by oxidative dehydrogenation of allyl alcohols of the present invention is a palladium carboxyl obtained by reacting palladium acetate with carbon monoxide in acetic acid. It is a suspension compound obtained by reacting acetate with a nitrogen-containing compound or an acetic acid compound. Such suspension compounds can be prepared by known methods (I. Moiseev, Pure & Appl. Che.
m. 61, No. 10, pp. 175-176
2, 1989). The method for preparing such a suspension compound will be described in detail below.

First, an acetic acid solution containing palladium acetate is prepared. The amount of palladium acetate dissolved in acetic acid is not particularly limited as long as it is within the range in which palladium acetate is dissolved in acetic acid, but usually, from the viewpoint of cost and handleability of acetic acid solution, 1 part of palladium acetate is used per 100 parts by weight of acetic acid.
About 100 parts by weight is suitable. Glacial acetic acid is preferable as acetic acid.

Next, this acetic acid solution containing palladium acetate is reacted in a carbon monoxide atmosphere to form palladium carboxyl acetate. As for the flow of carbon monoxide, the flow amount of carbon monoxide is not particularly limited as long as all of palladium acetate can be converted to palladium carboxyl acetate, and is usually at room temperature to 70 ° C. for about 1 to 3 hours.
It is preferably distributed for 1.5 to 2 hours. The carbon monoxide atmosphere means that palladium acetate in an acetic acid solution can contact carbon monoxide, a method of bubbling carbon monoxide into an acetic acid solution, a method of stirring the acetic acid solution in a carbon monoxide atmosphere. Etc. can be adopted.

Further, the obtained palladium carboxylacetate is reacted with a nitrogen-containing compound or an acetic acid compound to obtain a suspension compound existing in suspension in acetic acid. As the nitrogen-containing compound or acetic acid compound, a compound that can react with palladium to form a bond or a complex can be used.

As such a nitrogen-containing compound, 1,10-phenanthroline having a tertiary nitrogen, 2,2-bipyridine, triethylamine, the general formula (1):

[0014]

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(Wherein R ¹ and R ² are the same or different and each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms), and a general formula (2): (CH ₃ ) ₂ N (CH ₂ ) _n N (CH ₃ ) ₂
(In the formula, n is an integer of 1 to 10) and the like are preferable amine compounds. Specific examples of the pyridine compound represented by the general formula (1) include pyridine, 4-methylpyridine,
2-methylpyridine, 2,6-dimethylpyridine and the like can be mentioned, and as the amine compound represented by the general formula (2), 1,2-di (N, N-dimethylamino) ethane,
1,3-di (N, N-dimethylamino) propane and the like can be mentioned.

The acetic acid compound is preferably an alkali metal acetate, and specific examples thereof include potassium acetate.

The amount of the nitrogen-containing compound or acetic acid compound used is at least a theoretical amount such that the total amount of palladium metal in palladium carboxylacetate can react with the nitrogen-containing compound or acetic acid compound to form a bond or a complex. Usually, the amount is 2-3 times the theoretical amount. For example, when the nitrogen-containing compound has one nitrogen atom, the amount of palladium acetate charged is 1 part by mole or more, and when there are two nitrogen atoms, the amount is 1 part by mole or more. The amount of the acetic acid compound used is 2 parts by mole or more based on 1 part by mole of the palladium acetate.

According to the above-mentioned report, for example, the nitrogen-containing compound is 1,10-phenanthroline (hereinafter referred to as Phe).
n may be abbreviated as n), the obtained suspension compound is Pd ₄ (Phen) ₂ (CO) ₂ (OCOCH
₃ ) ₄ It is estimated that the structure is _4, and in the above-mentioned paper, such a suspension compound is used in the acetoxylation reaction of an olefin.

The present invention uses such a known suspension compound as a catalyst for the oxidative dehydrogenation reaction for producing α, β-unsaturated carbonyl compounds from allyl alcohols. Such a suspension compound is usually used as a suspension system (acetic acid solution) as a homogeneous catalyst.

In the present invention, α, β-unsaturated carbonyl compounds are produced from allyl alcohol by using a precipitate obtained through a step of adding an aromatic solvent and a step of contacting with oxygen to the suspension compound. It can also be used as a catalyst for the oxidative dehydrogenation reaction.

Benzene is preferred as the aromatic solvent,
The amount used is 30 parts by weight or more based on 100 parts by weight of a suspension solution (acetic acid solution) containing the suspension compound. Preferably, it is 100 to 2000 parts by weight. If the amount is less than 30 parts by weight, it is difficult to precipitate the suspension compound.

The step of bringing into contact with oxygen means bringing the suspension compound or the precipitate into contact with oxygen, and includes the case of contacting with oxygen in the air as well as the case of supplying and contacting with oxygen. . The step of contacting with oxygen is, for example,
When the aromatic solvent is added to the suspension compound, it means a state in which the suspension compound or the precipitate comes into contact with oxygen, or a state in which after the precipitate is separated, oxygen is contained in the voids of the precipitate.

Although the precipitate is black and its structure has not been clarified, when the nitrogen-containing compound is Phen, Pd (Phen) (OCOCH ₃ ) ₂ or P
d ₄ (Phen) ₂ (OCOCH ₃ ) _n (n = 1 to 3)
It is estimated that it may be.

The fact that a precipitate is formed by the steps of adding an aromatic solvent and contacting with oxygen to the above-mentioned suspension compound is not described in the above-mentioned report, and the present inventor has not described it. The present inventor has also found for the first time that the precipitate is used as a catalyst for oxidative dehydrogenation reaction for producing α, β-unsaturated carbonyl compounds from allyl alcohols. It is a thing.

The thus obtained precipitate can be treated as a heterogeneous catalyst as it is as an acetic acid solution or after removing the supernatant (decantation). In most cases, the suspension solution containing the suspension compound is treated as a homogeneous catalyst and is added to the reaction system as a solution as it is, so that the catalyst is separated from the reaction system after the oxidative dehydrogenation reaction. Was very difficult (complex operation), but a heterogeneous catalyst consisting of a precipitate facilitates separation of the catalyst from the reaction system after the oxidative dehydrogenation reaction,
It is also possible to repeatedly use the catalyst. The catalyst can be separated by various known methods such as a natural sedimentation method and a centrifugal separation method.

In the present invention, allyl alcohols are subjected to oxidative dehydrogenation reaction in an oxygen atmosphere in the presence of a catalyst comprising the above-mentioned suspension compound or precipitate to produce α, β-unsaturated carbonyl compounds.

The allyl alcohols are represented by the general formula (3):

[0028]

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There is no particular limitation as long as it is a compound having a structure represented by the formula (1), and it can be changed from a low molecular weight compound such as allyl alcohol or a derivative thereof to a high molecular weight compound (polymer) partially having the above structure. Can also be applied.
For example, allyl alcohols are represented by the general formula (4):

[0030]

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In the case of the compound represented by R ³ , R ³ and R
⁴ , R ⁵ and R ⁶ are the same or different and each is a hydrogen atom, a linear or branched saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, a linear or branched saturated alicyclic group. 1 to 6 carbon atoms such as group hydrocarbon group, unsaturated alicyclic hydrocarbon group, or aromatic hydrocarbon group
32 hydrocarbon groups and the like (provided that R ³ or R ⁴ and R ⁵ are partially bonded to each other to form an unsaturated alicyclic structure), and various functional groups such as carboxy group and cyano group. Etc. Specific examples of such allyl alcohols include allyl alcohol, cinnamyl alcohol, geraniol, nerol, 2-hexen-1-ol, 3-methyl-2-buten-1-ol, 1-hydroxy-2,4. -Dimethylmethanocyclohexene, 4-methyl-3-penten-2-ol, myrtenol and the like.

As the α, β-unsaturated carbonyl compound, allyl alcohols having the structure represented by the general formula (3) are obtained by oxidative dehydrogenation reaction of the general formula (4):

[0033]

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A compound having a structure represented by

In the oxidative dehydrogenation reaction of the present invention, the amount of the catalyst used is such that the content of palladium in the catalyst is usually 0.01 to 2 with respect to the allyl alcohol as a raw material.
It is about 5 mol%, preferably 0.5 to 10 mol%.
If it is less than 0.01 mol%, a sufficient reaction rate cannot be obtained because the catalytic effect is low. On the other hand, if it exceeds 25 mol%, there are disadvantages in terms of catalyst cost and catalyst separation work.

The oxidative dehydrogenation reaction of the present invention does not necessarily have to be carried out in the presence of a solvent, but it is preferably carried out in an organic solvent system from the viewpoint of the yield of the obtained α, β-unsaturated carbonyl compounds. . In particular, as the organic solvent, it is preferable to use at least one selected from aromatic hydrocarbons, carboxylic acids, esters, alkyl halides and halogenated carbons.

Among the above organic solvents, aromatic hydrocarbons include benzene, toluene, xylene, ethylbenzene,
Examples thereof include isobutylbenzene and tetralin. Examples of carboxylic acids include acetic acid, propionic acid, butyric acid, isobutyric acid and the like. Examples of the esters include methyl acetate, ethyl acetate, isobutyl acetate, methyl propionate, ethyl propionate, isobutyl propionate and the like. The alkyl halides include dichloromethane, trichloromethane, dichloroethane, trichloroethane,
Examples thereof include dichloropropane, dichlorobutane, trichloropropane, trichlorobutane, tetrachloropropane and tetrachlorobutane. Examples of the halogenated carbon include carbon tetrachloride, hexachloroethane, octachloropropane and the like.

The production of the α, β-unsaturated carbonyl compound of the present invention is usually carried out by placing the catalyst in a reaction vessel, adding an organic solvent and allyl alcohol which is a reaction raw material thereto, and carrying out a predetermined reaction in an oxygen atmosphere. The reaction is carried out by carrying out the oxidative dehydrogenation reaction for a predetermined reaction time at the reaction temperature.

The reaction temperature is usually about 5 to 150 ° C. In particular, it is preferable that the temperature is not lower than the freezing point and not higher than the boiling point of the organic solvent or the raw material allyl alcohol, and is 10 to 80.
C is preferred. When the temperature is lower than 5 ° C, the organic solvent is solidified, which is disadvantageous to the reaction. When the temperature exceeds 150 ° C, the yield of α, β-unsaturated carbonyl compounds is lowered, which is also disadvantageous in terms of heat cost. The reaction time varies depending on the type of allyl alcohol as a raw material and the reaction temperature, but is usually about 2 to 30 hours. The term "in an oxygen atmosphere" refers to a state in which air or oxygen gas is supplied, a state in which these are bubbled, and the like.

One of the features of the production method of the present invention is that the oxidative dehydrogenation reaction can be carried out at normal pressure by employing the above-mentioned specific catalyst to obtain α, β-unsaturated carbonyl compounds in good yield. However, the pressurizing condition is not excluded.

[0041]

According to the present invention, allyl alcohols are subjected to oxidative dehydrogenation reaction under safe and mild conditions to obtain α, β-
Unsaturated carbonyl compounds can be produced in a high yield of about 60 to 95 mol%. Further, among the catalysts used in the present invention, a catalyst composed of a precipitate can be used as a heterogeneous catalyst,
It can be easily separated from the reaction system and is easily discarded.

[0042]

The present invention will be described in more detail with reference to the following examples and comparative examples, but the present invention is not limited to these examples.

Example 1 (1) (Preparation of catalyst for oxidative dehydrogenation reaction) 3.5 ml of glacial acetic acid (3.67 g) was added to a 20 ml round bottom flask.
g) and 0.03 g of palladium acetate were added, and the reaction was carried out at 50 ° C. for 1.5 hours in a carbon monoxide atmosphere to obtain yellow crystals of palladium carboxyl acetate. Then, 1,10-phenanthroline (0.10 mmol) corresponding to twice the theoretical amount of palladium metal present in the flask (0.05 mmol) was added, and the reaction was carried out at 50 ° C. for 0.5 hours, and the reaction was carried out. A suspension of fine suspension was obtained. This suspension solution is called catalyst A.

(2) (Preparation of catalyst for oxidative dehydrogenation reaction) To the catalyst A obtained in (1) above, 15 ml of benzene was added. A precipitate gradually formed, and after separating this precipitate, the supernatant was removed by decantation. The separation work was performed in an oxygen atmosphere (under an air atmosphere) to obtain a black solid.
The obtained precipitate is called catalyst B.

(3) (Oxidative dehydrogenation reaction) A 20 ml Schlenk tube equipped with a reflux condenser and a cock and capable of maintaining a sealed state has a palladium content of 0.0
After adding 3 mmol of catalyst B (precipitate), 5 ml of benzene as a solvent and 1.5 mmol of cinnamyl alcohol as a reaction raw material were added, the Schlenk tube was replaced with oxygen, and a balloon was attached to the cock to keep the oxygen atmosphere. It was While stirring in an oil bath with a magnetic stirrer, at 50 ° C, 24
A time reaction was performed. The obtained α, β-unsaturated carbonyl compounds (cinnamylaldehyde) were analyzed by gas chromatography. Table 1 shows the conversion rate and the yield. The conversion rate refers to the rate of conversion of the raw materials, and the yield refers to the rate of conversion to the target product among all the raw materials.

Examples 2 to 23 Comparative Examples 1 to 3 Types of allyl alcohols as raw materials and types of catalysts (the above A)
Or B, or the type of nitrogen-containing compound or acetic acid compound), reaction temperature, reaction time, and solvent except that at least one of them is changed as shown in Table 1.
The same was done. Table 1 shows the conversion and selectivity of α, β-unsaturated carbonyl compounds.

[0047]

[Table 1]

In Table 1, Pd (OAc) ₂ is palladium acetate, PCA is palladium carboxyl acetate,
Benzene acetic acid refers to a 1: 1 (weight ratio) mixture of benzene and acetic acid.

[Procedure amendment]

[Submission date] June 19, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 9

[Correction method] Change

[Correction contents]

Embedded image Wherein the α, β-unsaturated carbonyl compound is a compound having a structure represented by the following general formula (4):

Embedded image A compound having a structure represented by:
Or the catalyst according to item 8.

[Procedure amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 12

[Correction method] Change

[Correction contents]

Embedded image Wherein the α, β-unsaturated carbonyl compound is a compound having a structure represented by the general formula (4):

Embedded image The method according to claim 10 or 11, which is a compound having a structure represented by:

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction contents]

[0028]

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[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0030

[Correction method] Change

[Correction contents]

[0030]

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──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location // C07B 61/00 300 C07B 61/00 300

Claims (12)

[Claims] 1. Oxidative dehydrogenation of allyl alcohols comprising a suspension compound obtained by reacting palladium carboxyl acetate obtained by reacting palladium acetate with carbon monoxide in acetic acid with a nitrogen-containing compound or an acetic acid compound. A catalyst for reacting to produce α, β-unsaturated carbonyl compounds. 2. The nitrogen-containing compound is 1,10-phenanthroline, 2,2-bipyridine, triethylamine, a compound represented by the general formula (1): (In the formula, R ¹ and R ² are the same or different and each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms), and a general formula (2): (CH
₃ ) ₂ N (CH ₂ ) _n N (CH ₃ ) ₂ (where n is 1 to
The catalyst according to claim 1, which is at least one selected from the amine compounds represented by (integer of 10). 3. The catalyst according to claim 1, wherein the acetic acid compound is an alkali metal acetate. 4. A step of further adding an aromatic solvent to a palladium carboxylacetate obtained by reacting palladium acetate and carbon monoxide in acetic acid, and a suspension compound obtained by reacting a nitrogen-containing compound or an acetic acid compound. And a precipitate obtained through the step of contacting with oxygen. 5. The nitrogen-containing compound is 1,10-phenanthroline, 2,2-bipyridine, triethylamine, a compound represented by the general formula (1): (In the formula, R ¹ and R ² are the same or different and each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms), and a general formula (2): (CH
₃ ) ₂ N (CH ₂ ) _n N (CH ₃ ) ₂ (where n is 1 to
The integer according to claim 4, which is at least one selected from the amine compounds represented by the formula (10: integer). 6. The precipitate according to claim 4, wherein the acetic acid compound is an alkali metal acetate. 7. The aromatic solvent is benzene,
The precipitate according to 5 or 6. 8. An allyl alcohol comprising the precipitate according to claim 4, 5, 6 or 7 is subjected to oxidative dehydrogenation reaction to obtain α,
A catalyst for producing β-unsaturated carbonyl compounds. 9. An allyl alcohol is represented by the general formula (3): Wherein the α, β-unsaturated carbonyl compound is a compound having a structure represented by the following general formula (4): A compound having a structure represented by:
Or the catalyst according to item 8. 10. An α, β-unsaturated carbonyl compound which is characterized by oxidatively dehydrogenating allyl alcohol in an oxygen atmosphere in the presence of the catalyst according to claim 1, 2, 3 or 8. Manufacturing method. 11. The oxidative dehydrogenation reaction is carried out in at least one organic solvent selected from aromatic hydrocarbons, carboxylic acids, esters, alkyl halides and halogenated carbons. The manufacturing method according to claim 10. 12. The allyl alcohol is represented by the general formula (3): Wherein the α, β-unsaturated carbonyl compound is a compound having a structure represented by the following general formula (4): The method according to claim 10 or 11, which is a compound having a structure represented by: