JPH013145A - Method for producing carboxylic acid - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing carboxylic acid, and more specifically, the present invention relates to a method for producing carboxylic acid, and more specifically, a method for producing carboxylic acid using the so-called Kotsuto reaction, in which an olefin and water are reacted in the presence of an acid catalyst. The present invention relates to a method for producing a carboxylic acid that can be esterified into a carboxylic acid ester that has excellent hydrolysis resistance and can be suitably used, for example, in the fields of paints and solvents.

[Prior art and its problems] In the presence of an acid catalyst such as hydrochloric acid, sulfuric acid, phosphoric acid, or boron trifluoride, an olefin, carbon monofluoride, and water are reacted.
A method for producing a carboxylic acid having one more carbon atoms than the raw material olefin is well known as the Kotsuto reaction.

Various methods for producing carboxylic acids using this Kotsuho reaction have been proposed in the past.

It is known that the reaction product obtained by the conventional method using the Kotsuho reaction is a mixture of carboxylic acids, mainly tertiary carboxylic acids.
No. 5048, JP-A No. 49-48818, R,
Yoneda et al., Chemistry Letter, Slow, 807-610
, Yoshie Soma et al., Oil Chemistry, Vol. 30, No. 5, No. 265-2
69 pages (1981), Yoshie Soma, Organic Synthetic Chemistry, No. 4
See Vol. 1, No. 6, pp. 561-569 (1983), etc. ]
.

However, carboxylic acid esters obtained by esterifying these reaction products cannot be said to have sufficient hydrolysis resistance, and are not necessarily suitable for use in the fields of paints and solvents, for example.

[Objective of the Invention] The object of the present invention is to solve the above-mentioned problems and to provide a carboxylic acid ester that can be esterified into a carboxylic acid ester that has excellent hydrolysis resistance and can be suitably used in the fields of paints and solvents, for example. An object of the present invention is to provide a method for producing acid.

[Means for achieving the above object] In order to achieve the above object, as a result of extensive studies, the inventor identified a specific olefin, carbon monoxide, and water in the presence of a specific acid catalyst. When reacted under the following conditions, esterification is difficult due to steric hindrance, and when esterified, a carboxylic acid is obtained that provides a stable esterified product with sufficient hydrolysis resistance. We discovered this and arrived at this invention.

That is, the outline of this invention is as follows: a catalyst made of sulfuric acid, a catalyst made of sulfuric acid and phosphoric acid, a catalyst made of boron trifluoride and water, a catalyst made of sulfuric acid, boron trifluoride and water, a catalyst made of sulfuric acid, phosphoric acid and trifluoride. At least one selected from the group consisting of a catalyst consisting of boron oxide and water and a catalyst consisting of phosphoric acid, boron trifluoride and water,
isobutylene oligomer, carbon monoxide and water in the presence of a catalyst whose acid strength is in the range of -8.2 to -6,
This is a method for producing carboxylic acid, which is characterized in that the reaction is carried out under pressure conditions of 2 to 40 kg/cm2.

In the isobutylene oligomer, the inbutylene molecule is
For example, it is an oligomer formed by polymerizing about 2 to 12 molecules in the presence of a Lewis acid catalyst such as hydrochloric acid, sulfuric acid, or boron trifluoride. Usually, oligomers with a double bond at the end are synthesized. However, it also includes those whose unsaturated bonds are sequentially rearranged into the interior of the molecule by catalytic action and isomerized into internal olefins.

Preferred isobutylene oligomers can be represented by the following general formulas [I] and [nl, for example.

・・・・・・ [I] (However, m represents an integer from 0 to 10)...Fist...
[nl (However, n represents an integer from 0 to 10.) In this invention, these isobutylene oligomers may be used alone or in a mixture of two or more.

Particularly preferred isobutylene ribomers are dimers and trimers of imbutylene. In the dimer of inbutylene, 2,4,4-)limethylpentene-1 and 2
, 4.4-) 80% or more in total of remethylpentene-2, and 5 to 5% in total of 2,3.4-) remethylpentene-1 and 2,3.4-trimethylpentene-2
diisobutylene mixtures containing at least 15% of these;
and in the trimer of inbutylene, 2.4,4,
8.8-Pentamethyl-1-hexene and 2°4.4
．． B, a triyne butylene mixture containing 80% or more of a branched C12 olefin such as 8-pentamethyl-2-hexene is preferred.

The carbon oxide is preferably pure, but carbon monoxide-containing gases obtained from water gas, generator gas, coke oven gas, etc. can also be used.

The water is most preferably pure, and distilled water, ion exchange water, etc. can also be used.

The catalysts used in this invention include a catalyst made of sulfuric acid, a catalyst made of sulfuric acid and phosphoric acid, a catalyst made of boron trifluoride and water, a catalyst made of sulfuric acid, boron trifluoride and water, sulfuric acid, phosphoric acid, It consists of at least one selected from the group consisting of a catalyst consisting of boron trifluoride and water and a catalyst consisting of phosphoric acid, boron trifluoride and water, and may further contain a metal oxide.

Preferred catalysts include, for example, a catalyst consisting of sulfuric acid alone, a catalyst consisting of a combination of sulfuric acid and phosphoric acid, a catalyst consisting of a combination of sulfuric acid and boron trifluoride, a catalyst consisting of a combination of phosphoric acid and boron trifluoride, etc. It is.

In this invention, regardless of which catalyst is used, it is important that the acid strength of the catalyst used is -9,2 to -6 (preferably -9,0 to -6,5). .

Here, the acid strength refers to Hammett's acidity function HO.

Furthermore, if the acid strength of the catalyst used is greater than -6, the carbonylation reaction will be difficult to induce, and the tendency for olefin polymerization or isomerization to occur will increase. Also, -9,2
If it is smaller than , while retaining the inbutylene skeleton,
Carbonylation becomes more likely to occur, and cleavage to inbutylene becomes more intense, resulting in a greater tendency to produce a large amount of pivalic acid (C5 acid).

When using a catalyst consisting of a combination of sulfuric acid and phosphoric acid and having a value within the above acid strength range, the concentration of sulfuric acid in the catalyst is usually 30
~90% by weight, preferably 40-80% by weight.

In this mixture consisting of sulfuric acid and phosphoric acid, Jdi,
Water contained in the acid and phosphoric acid or added separately may also be present. Its water content is usually 25% by weight
It is as follows.

Regarding catalysts consisting of a combination of sulfuric acid and boron trifluoride, catalysts consisting of a combination of phosphoric acid and boron trifluoride, etc.
The concentration of each of sulfuric acid, phosphoric acid, or boron trifluoride that should be used in order to obtain a catalyst having a value within the above acid strength range can be appropriately determined by experiment.

There are no particular restrictions on the method for preparing the catalyst; for example, a catalyst solution containing sulfuric acid, phosphoric acid, or boron trifluoride may be prepared by pre-mixing sulfuric acid, phosphoric acid, or boron trifluoride using a normal mixing operation. Then, when using the catalyst, this catalyst liquid may be used as it is or diluted, or after adding and mixing a metal oxide to this catalyst liquid, this metal oxide-containing catalyst liquid is added to the reaction system. May be added.

Sulfuric acid, phosphoric acid or boron trifluoride and a metal oxide may be mixed in advance to prepare a catalyst solution, and this metal oxide-containing catalyst liquid may be used as described above.

Furthermore, each component forming the catalyst of the present invention (catalyst component) and, if necessary, each of the metal oxides may be added simultaneously or sequentially to the mixture of isobutylene oligomer, carbon oxide, and water as raw materials. Good too. In addition, when adding catalyst components sequentially, there is no restriction on the order in which the catalyst components are added.

Alternatively, the catalyst component may be added to the reaction vessel, and the raw materials may be added thereto.

In any case, when isobutylene oligomer, carbon monoxide, and ice react, a catalyst consisting of sulfuric acid, a catalyst consisting of sulfuric acid and phosphoric acid, a catalyst consisting of boron trifluoride and water, '&i acid, trifluoride At least one selected from the group consisting of a catalyst consisting of boron and water, a catalyst consisting of sulfuric acid, phosphoric acid, boron pentafluoride and ice, and a catalyst consisting of phosphoric acid, boron trifluoride and water, and if necessary metal oxidation. It suffices if the state is such that a catalyst containing the substance is present.

Examples of metal oxides include cuprous oxide, silver oxide, gold oxide, etc., and they can also be used as a mixture with metallic copper or divalent copper compounds, but cuprous oxide is preferred. .

When using the metal oxide, in particular cuprous oxide, as a component of the catalyst, the amount of this metal oxide used can be as follows: a catalyst consisting of sulfuric acid, a catalyst consisting of sulfuric acid and phosphoric acid, boron difluoride and water. a catalyst consisting of sulfuric acid, boron trifluoride and water; a catalyst consisting of sulfuric acid, phosphoric acid, boron trifluoride and water; and a catalyst consisting of phosphoric acid, boron trifluoride and water. The amount is usually 0.1 to 4% by weight, preferably 0.2 to 2% by weight, based on the weight of at least one type.

When the weight of this metal oxide is less than 0.1% by weight, the production of olefin polymerized oil tends to increase, and 4% by weight
Even if it exceeds 100%, the reaction results do not improve much, and on the contrary, the acid strength of the catalyst increases due to the production of water, and the carbonylation activity may decrease.

The amount of the catalyst to be used is such that the catalyst contains at least 3 moles of sulfuric acid, boron trifluoride, or sulfuric acid and boron trifluoride per mole of olefin in the isobutylene oligomer. It would be good if it was 5.

In the method of this invention, the reaction pressure (gauge pressure) is 2
-40 kg/cm2, preferably 4-20 kg/cm layer 2 for women.

The reaction pressure is 40kg/c+m? If it exceeds the carboxylic acid which gives an esterified product with poor hydrolysis resistance, for example 2.
A large amount of 2,4,4-tetramethylpentanoic acid is produced. The reason for this is that under relatively high pressure conditions exceeding 40 kg/c layer 2, isobutylene oligomer maintains its skeleton and becomes 2,2,4.4-tetramethylpentanoic acid, whereas 2- 40 kg/c Under the relatively low pressure of Layer 2, the carbon skeleton of the isobutylene oligomer undergoes a series of isomerizations, resulting in a chemically more stable compound than 2,2,4,4-tetramethylpentanoic acid, in other words, an inorganic compound. This seems to be because it becomes an active carboxylic acid. On the other hand, the reaction pressure is 2
If it is lower than kg/cm2, only olefin will be polymerized and the reaction may not proceed sufficiently.

The reaction temperature is usually 0 to 50°C. Reaction temperature is 0℃
If it is lower than , the reaction rate will decrease. - On the other hand, if the temperature is higher than 50°C, sulfuric acid sludge, sulfuric esters, etc. will increase.

The reaction time is usually sufficient for a total of 45 to 120 minutes as the feeding time and 30 to 120 minutes as the stirring time.

In the method of this invention, the target carboxylic acid is produced by the Kotsuto reaction. For example, when diisobutylene is used as a raw material, it has excellent hydrolysis resistance when esterified. 2-ethyl-2,3,3-)dimethylbutanoic acid: CH3CH3 CH3-G-G -(J2- CH3 CH3C00H 2-isopropyl-2,3-dimethylbutanoic acid; CH3
CH3CH3 CH3-CH-C-CH-CH3 0OH 2,2,3,3-tetramethylpentanoic acid; C0OHC
H3 2,2,3,4-tetramethylpentanoic acid; CH30H
A mixture of 3CH3 and other carboxylic acids is produced simultaneously.

Furthermore, the product may contain not only tertiary carboxylic acid but also secondary carboxylic acid.

After completion of the reaction, organic solvents such as aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane, and n-octane; aromatic hydrocarbons such as benzene, toluene, and xylene are extracted from the reaction product liquid obtained. After extraction using the carboxylic acid, the extraction solvent is removed by washing with water to obtain a carboxylic acid as a mixture containing tertiary carboxylic acid as a main component.

This carboxylic acid can be used as a composition itself or as a reaction product obtained by subjecting a carboxylic acid to an esterification reaction (the main component is an ester mixture of carboxylic acids, containing a small amount of unreacted carboxylic acid). Sometimes I do.

) can be used for various purposes. Further, when each carboxylic acid in the mixture of carboxylic acids is used for various purposes, the mixture of carboxylic acids may be subjected to a known separation and purification treatment to separate each carboxylic acid.

In the method of this invention, the catalyst liquid can be recovered from the extraction solvent, and the recovered catalyst liquid can be circulated to the reaction system for reuse. When a metal oxide is used as a component of the catalyst, it is preferable to recover the catalyst liquid under an atmosphere in which the metal oxide cannot be oxidized. When the catalyst liquid is recovered in an oxidizing atmosphere, the metal oxide is oxidized and the catalyst activity is lowered, and when the recovered catalyst is reused, the yield of carboxylic acid may be lowered.

The carboxylic acids obtained by the method of the present invention are all carboxylic acids that yield esterified products with excellent hydrolysis resistance, such as 2-ethyl-2,2,3-)limethylbutanoic acid, 2-isopropyl-2,3- dimethylbutane,
2,2,3.3-tetramethylpentanoic acid and 2,2
, 3,4-tetramethylpentanoic acid and the like, it can be suitably used as an esterified product in the fields of paints and solvents, for example.

[Effects of the Invention] According to the present invention, (1) It is possible to obtain a stable carboxylic acid that is not susceptible to esterification due to its own steric hindrance and has excellent hydrolysis resistance when esterified. (2) An industrially excellent method for producing carboxylic acids that has the following advantages: (2) If the catalyst liquid is recovered and reused, the catalyst can be used effectively; can be provided.

[Example] Next, Examples and Comparative Examples of the present invention will be shown to further specifically explain the present invention.

(Example 1) Catalyst 150+ consisting of an aqueous solution containing 85% by weight of sulfuric acid
After nJJ was charged into a reaction vessel and the interior of the reaction vessel was sufficiently replaced with carbon monoxide, carbon monoxide was absorbed while stirring until a saturated state was reached.

Next, while maintaining the reaction temperature at 25°C and the reaction pressure at 5 kg/c+*2, 0.3 mol of diisobutylene was supplied into the reaction vessel, and this diimbutylene and carbon monoxide were allowed to react. Ta. Note that carbon monoxide, which was consumed and decreased during the reaction, was replenished to maintain a predetermined pressure.

After 1.5 hours of reaction time had elapsed, the supply of diisobutylene was stopped, and the mixture was stirred for an additional 1 hour. Then an equal amount of water was added.

The reaction mixture thus obtained was diluted three times with water, and then extracted three times with 7200 m of n-hexane.

Next, n-hexane was removed by distillation to obtain a carboxylic acid having the composition shown in Table 1.

The results are shown in Table 1.

Note that the composition of the reaction product was measured by NMR spectrum.

(Example 2.3) The same procedure as in Example 1 was carried out except that the reaction pressure was set to the pressure shown in Table 1.

The results are shown in Table 1.

(Example 4) The same as in Example 1 except that instead of the catalyst consisting of an aqueous solution containing 85% by weight of sulfuric acid, a catalyst consisting of an aqueous solution containing 64% by weight of sulfuric acid and 29% by weight of phosphoric acid was used. It was carried out in the same manner.

The results are shown in Table 1.

(Example 5.6) In Example 4, the reaction was carried out in the same manner as in Example 1, except that the reaction pressure was set to the pressure shown in Table 1.

The results are shown in Table 1.

(Example 7) In Example 1, a catalyst consisting of an aqueous solution containing 66% by weight of sulfuric acid and 22% by weight of boron trifluoride was used instead of the catalyst consisting of an aqueous solution containing 85% by weight of sulfuric acid, and the reaction temperature was changed. The same procedure as in Example 1 was carried out except that the temperature was 5°C.

The results are shown in Table 1.

(Example 8.9) Example 7 was carried out in the same manner as in Example 1 except that the reaction pressure was set to the pressure shown in Table 1.

The results are shown in Table 1.

(Example 10) In Example 1, instead of the catalyst consisting of an aqueous solution containing 85% by weight of sulfuric acid, a catalyst consisting of an aqueous solution containing 53% by weight of phosphoric acid and 37% by weight of boron trifluoride was used, and the reaction temperature was changed. The test was carried out in the same manner as in Example 1 except that the temperature was set to 80'0.

The results are shown in Table 1.

(Example 11.12) In Example 10, the reaction was carried out in the same manner as in Example 1, except that the reaction pressure was changed to the pressure shown in Table 1.

The results are shown in Table 1.

(Comparative Example 1.2) A carboxylic acid was produced in the same manner as in Example 1 except that the reaction pressure was changed to the pressure shown in Table 1.

The results are shown in Table 1.

As is clear from Table 1, in all of the comparative examples, 2,2,4,4-tetramethylpentanoic acid was produced which had insufficient hydrolysis resistance when esterified compared to Example 1. There was a lot of it.

(Comparative Example 3.4) A carboxylic acid was produced in the same manner as in Example 4 except that the reaction pressure was changed to the pressure shown in Table 1.

The results are shown in Table 1.

As is clear from Table 1, in all of the comparative examples, 2,2,4,4-tetramethylpentanoic acid was produced which had insufficient hydrolysis resistance when esterified, compared to Example 4. There was a lot of it.

(Comparative Example 5.6) A carboxylic acid was produced in the same manner as in Example 7 except that the reaction pressure was changed to the pressure shown in Table 1.

The results are shown in Table 1.

As is clear from Table 1, in all of the comparative examples, 2,2,4,4-tetramethylpencunic acid had insufficient hydrolysis resistance when esterified, compared to Example 7. The amount produced was large.

(Comparative Examples 7 and 8) Carboxylic acids were produced in the same manner as in Example 10, except that the reaction pressure was changed to the pressure shown in Table 1.

The results are shown in Table 1.

As is clear from Table 1, in all of the comparative examples, 2,2,4,4-tetramethylpentanoic acid was produced which had insufficient hydrolysis resistance when esterified, compared to Example 1O. There was a lot of it.

(Comparative Example 9) In Example 10, 41% by weight of phosphoric acid and 51% by weight of boron trifluoride were used instead of the catalyst consisting of an aqueous solution containing 53% by weight of phosphoric acid and 37% by weight of boron trifluoride. A carboxylic acid was produced in the same manner as in Example 10, except that a catalyst consisting of an aqueous solution was used, the reaction temperature was 5° C., and the reaction pressure was 75 kg/C2.

The results are shown in Table 1.

As is clear from Table 1, in this comparative example, the amount of 2,2,4,4-tetramethylpentanoic acid produced, which had insufficient hydrolysis resistance when esterified, was higher than in Example 10. There were many.

(Example 13) 2,2,4°4-tetramethylpentanoic acid synthesized in the same manner as in Comparative Example 4 using a catalyst consisting of a mixed solution of sulfuric acid and phosphoric acid [hereinafter and in Table 1, carboxylic acid It is called (A). ] and ]2-ethyl2.3.3-
Mixtures of limethylbutanoic acid, 2-isopropyl-2,3-dimethylbutanoic acid, 2,2,3.3-tetramethylpentanoic acid, 2,2,3.4-tetramethylpentanoic acid and other tertiary carboxylic acids [Hereinafter and in Table 1, it is referred to as carboxylic acid (B).] ] [Carboxylic acid (A): Carboxylic acid (B) = 53 mol%: 47 mol%] 50. Charge Og and 200 mJL of methanol into a stainless steel autoclave, and heat to 225°C.
The methyl esterification reaction was carried out by stirring for 12 hours under these conditions.

Gas chromatography analysis of the obtained product revealed that the conversion rate to methyl ester was 56%. Furthermore, when the unreacted acid was analyzed by gas chromatography, it was found that the J soil of carvone M (A) and carvone M (B) had changed to 17 mol % to 283 mol %.

This revealed that carboxylic acid (B) has significantly lower esterification reactivity than carboxylic acid (A).

(Example 14) Carboxylic acid mixture synthesized in the same manner as in Comparative Example 4 using a catalyst consisting of a mixed solution of sulfuric acid and phosphoric acid [Carboxylic acid (A): Carboxylic acid (B) = 53 mol%: 47 Mol%] 8.7 g and 50 ml of hexamethylphosphoric triamide were placed in a Mitsu 1-1 flask with a volume of 100 m, and 2.4 g of sodium hydroxide containing 2.43 g of sodium hydroxide was added.
A 5% aqueous solution was added and stirred at room temperature for 30 minutes. moreover,
10 g of methyl iodide was added.

The liquid immediately became cloudy and sodium iodide precipitated.

The reaction solution was poured into 50mM water and extracted with ether. After washing the extract with water, it was distilled to obtain ester of carboxylic acid (A):
Esterification reactivity of carboxylic acid CB) %: 47 mol%
7.2 g of methyl ester of a carboxylic acid mixture consisting of:

Then, 1.2 mJ1 of this methyl ester mixture was added to 50
Take 0mJ17 Lasco and add 0.0m to this. I N NaO■
Solution (water diethylene glycol monomethyl ether-1
:10 mixture) After adding 400 mJL, the mixture was left in a constant temperature bath at 80° C. for 50 hours to perform alkaline hydrolysis.

Thereafter, when the reaction solution was analyzed by gas chromatography, it was found that the ratio of ester of carboxylic acid (A) to ester of carboxylic acid (B) had changed to 27 mol% to 8 mol%. It has become clear that the ester of A) is less susceptible to hydrolysis than the ester of carboxylic acid (B).

(Hereafter, margin)

Claims (1)

[Claims] (1) Catalyst consisting of sulfuric acid, catalyst consisting of sulfuric acid and phosphoric acid, catalyst consisting of boron trifluoride and water, catalyst consisting of sulfuric acid, boron trifluoride and water, sulfuric acid, phosphoric acid, boron trifluoride and water and at least one type selected from the group consisting of a catalyst consisting of phosphoric acid, boron trifluoride, and water, the acid strength of which is -9.2 to
-6 isobutylene oligomer, carbon monoxide and water at a pressure of 2 to 40 kg/cm.
A method for producing a carboxylic acid, characterized by carrying out the reaction under the conditions of ^2.