JPH01193258A - Production of butylene oxides - Google Patents

Abstract

PURPOSE:To easily obtain above compound useful as a stabilizer, etc., in high yield and selectivity, by oxidizing an olefinic compound with an organic hydroperoxide in the presence of metallic molybdenum which is essentially insoluble under the reaction condition. CONSTITUTION:A 4C olefinic compound (e.g., isobutylene, trans-2-butene or cis-2-butene) is converted to corresponding epoxy compound with an organic hydroperoxide (e.g., ethylbenzene hydroperoxide). The epoxidization can be carried out in high specificity and selectivity by using 0-valent metallic molybdenum catalyst which is essentially insoluble in the organic reaction system. The catalyst is generally powder having particle diameter of several mum-about 10mum. The reaction temperature is 60-120 deg.C, preferably 75-110 deg.C. The process has various advantages such as easy recovery of the expensive catalyst and easy purification process of the objective compound which is free from contamination with the catalyst.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for producing a corresponding epoxy compound in high yield by oxidizing an olefinic compound having 4 carbon atoms with an organic hydroperoxide. Regarding.

[Conventional technology]

The above-mentioned butylene oxides are epoxy compounds having 4 carbon atoms, and are important compounds as stabilizers for chlorinated solvents or as synthetic intermediates for various chemicals such as surfactants, polyethers, and butylene glycol.

Conventionally, butylene oxides have been produced from halohydrins, which are corresponding olefinic compounds having 4 carbon atoms, by dehydrohalogenation reaction with a basic substance such as calcium hydroxide. Furthermore, as an oxidation method that does not use halogen, epoxidation methods using peracids such as performic acid, peracetic acid, and perbenzoic acid have also been studied.

In addition, a method for producing butylene oxides by the epoxidation reaction of an olefinic compound having 4 carbon atoms using an organic hydroperoxide for oxidation has been well studied. Organometallic compounds are typically used.

[Problem to be solved by the invention]

The fatal drawback of the halohydrin method, which is a typical example of the above-mentioned conventional technology, is that all of the halogen, typically chlorine, consumed by halohydrin is converted into worthless inorganic salts such as calcium chloride, and a large amount of dilute aqueous solution is produced. It is a by-product.

Therefore, as oxidation methods that do not use halogen, oxidation methods using peracids and catalytic epoxidation methods using organic hydroperoxides as oxidizing agents have been studied.

However, in the epoxidation reaction using a peracid, the ring-opening reaction of butylene oxides due to the by-produced acid cannot be avoided, and this has not been put into practical use.

Further, in a catalytic epoxidation reaction using an organic hydroperoxide, butylene oxides are typically produced using an organic molybdenum compound as a catalyst, but there is a problem in that the selectivity is not high. Therefore, for example, JP-A-56-13
No. 3279 discloses a method in which an olefinic compound and an organic peroxide are reacted in the coexistence of an organometallic compound of a metal selected from Mo, V, and - and an organic amine compound.

However, even in this method, the epoxy selectivity based on organic hydroperoxide is at most 80%, and it has been desired to establish a method that would enable the production of butylene oxides with higher selectivity.

[Means and effects for solving the problem] In order to solve the above-mentioned problems, the present inventors have conducted extensive studies on the catalytic epoxidation reaction of an olefinic compound having 4 carbon atoms using an organic hydroperoxide. It was quite surprising that butylene oxides could be obtained with extremely high selectivity when this reaction was carried out in the presence of metallic molybdenum, rather than using an organometallic compound of molybdenum, that is, molybdenum oxide. Heading This is what led to the completion of the present invention.

That is, in the present invention, when converting an olefinic compound having 4 carbon atoms into a corresponding epoxy compound using an organic hydroperoxide,
This is a method for producing butylene oxides, characterized in that the reaction is carried out in the presence of metallic molybdenum, which is substantially insoluble under the reaction conditions.

The olefinic compounds having 4 carbon atoms in the present invention include isobutylene, trans-2-butene and cis-
It is a general term for 2-butene, and any of them can be used in the reaction of the present invention. Therefore, this reaction yields epoxy compounds corresponding to these olefins.

The metallic molybdenum used in the catalyst refers to the so-called molybdenum metal itself, and is generally commercially available in the form of a powder having a particle size of several microns to about 10 microns, which can be used. Epoxidation reactions using organic hydroperoxides using molybdenum compounds as catalysts are conventionally known. However, the molybdenum in this case is an oxide of molybdenum such as molybdenum acetylacetonate or molybdenum naphthenate, and is preferably used in a form soluble in the organic reaction system by forming it into an organometallic compound.

For example, Japanese Patent Publication No. 46-38770 discloses a method of epoxidizing an olefinically unsaturated compound with an organic hydroperoxide in the presence of various metal compounds, but it is also possible to use it as a finely powdered metal. It was stated that it was possible.

However, in this case it is assumed that the metal is eventually converted to a compound soluble enough to provide a catalytic amount of metal in solution in the reaction mixture, and the metal oxide compound is saturated (even solubilized). However, in the present invention, when epoxidizing an olefinic compound consisting of 4 carbon atoms with an organic hydroperoxide, a zero-valent and basically It has been discovered that by using metallic molybdenum that is insoluble in an organic reaction system, epoxidation can be carried out very specifically and with high selectivity.

Although the mechanism of action and effect of the present invention obtained using metallic molybdenum is completely unknown, even in the catalyst according to the present invention, molybdenum dissolution is observed, albeit very slightly, but this is not effective for this reaction. In other words, even when metal molybdenum is heated in a pure organic solvent such as cumene or ethylbenzene, it hardly dissolves and the solubility is below the detection limit, but when heated in a solvent containing organic hydroperoxide, As a result of the treatment, dissolution of molybdenum of several + ppea or more is observed. This is thought to be because the metal was oxidized and eluted as an organic compound of molybdenum oxide, but even if this material was recovered and used in the reaction catalyst of the present invention, no good results were obtained at all and the result was unsatisfactory. be.

Further, a powder catalyst of molybdenum trioxide, which is similarly insoluble in the organic reaction system, gives extremely unsatisfactory results, and the effects of the present invention can be obtained in a very specific manner by using metallic molybdenum.

Any hydroperoxide can be used as an epoxidizing agent, but those that are industrially easily available and effective are ethylbenzene hydroperoxide, cumenehydride, loba-oxide, and tcrt.
-Butyl hydroperoxide and the like can be exemplified. These organic hydroperoxides generally include their precursors, ethylbenzene, cumene, or other hydrocarbons, although any concentration of organic hydroperoxide to be subjected to the epoxidation reaction can be used. Generally, the concentration of organic hydroperoxide in the precursor is preferably 5 to 90% by weight.

Other reaction conditions can be arbitrarily determined depending on the type of hydroperoxide and the type of olefinic compound having 4 carbon atoms. Approximate reaction time is 10 minutes ~
It takes about 10 hours.

Further, the molar ratio of olefin to organic hydroperoxide, which is an oxidizing agent, is preferably in an excessive amount in order to avoid leaving any peroxide after the reaction, but according to the present invention, it is not necessary to have a large excess, i.e. , 1.1
Epoxide can be obtained with high selectivity at a molar ratio, preferably at a molar ratio close to a substantially stoichiometric ratio of about 1.2 molar ratio. Therefore,
Since the amount of unreacted raw material olefin is small, recovery is extremely easy and a rational process can be achieved.

The reaction temperature is 60-120" C1, preferably 75-110"
It is °C.

The reaction can be carried out in any format.For example, when carried out in a batch-type stirred tank, the catalyst can be easily separated by filtration or static sedimentation after the reaction, and can be recovered. The metal molybdenum catalyst can be recycled and reused as is.

Further, the target epoxy compound can be easily recovered from the obtained reaction solution by distillation after removing the raw material olefin.

〔Example〕

Hereinafter, the effects of the present invention will be explained in more detail with reference to Examples.

In addition, organic hydroperoxide (hereinafter abbreviated as HPO)
The selectivity of the standard butylene oxide If (hereinafter abbreviated as BO) and the BO selectivity based on the raw material olefin compound having 4 carbon atoms (hereinafter abbreviated as BU) are determined as follows.

(1) BO selectivity (%) based on HPO A - [Number of moles of BO generated in reaction] B = (Number of moles of HPO used in reaction) C - (Number of moles of HPO remaining after reaction) As BO selection selectivity based on HPO (A/(B-C)) ] F- (Number of moles of BU remaining after reaction) Based on BU base 8 Example-1 85 g of cumene and metal molybdenum powder (reagent, purity 99.9%) 1 in a 300 d stainless steel autoclave.
After putting in 0g and closing the lid, add 15.3g (0.27g) of isobutylene (hereinafter referred to as IBU) from a pressure-resistant holder.
3 mol) was added. The temperature was raised to 95°C while stirring, and then pumped to 67.1 g of a cumene solution containing 30-1% cumene hydroperoxide (0.1 g as HPO.
After feeding 132 mol) in about 30 minutes, an additional 1 mol was added at the same temperature.
After stirring for an hour, the temperature was lowered.

The obtained reaction solution was analyzed by gas chromatography and chemical analysis for cumene hydroperoxide, and the HPO conversion rate was 92.9%, and the HPO-based isobutylene oxide (hereinafter referred to as IBO) selectivity was 86.9%. ,
1811 conversion rate 39.7%, IBO selection rate based on IBU standards. IBO was obtained with a good reaction result of 4%. Furthermore, the surface analysis of the molybdenum powder used as the reagent used in this reaction was performed using XPS.
(X-RAM PHOTOELECTRON 5PECTRO3COP
When the oxidation state was investigated, the peak intensity ratio was 15% for zero valence, 39% for pentavalent, and 46% for hexavalent.

Example-2 In the same autoclave as in Example-1, cumene 23.
4g and 0.5g of metal molybdenum powder and 26.0g of IBU.
1 g (0,465 mol) charge, 100.5 g of cumene solution containing 60 wt% cumene hydroperoxide
(0.396 mol as HPO) was supplied over about 45 minutes, stirring was continued for 1 hour and the temperature was lowered. Similar analysis revealed very good reaction results with an HPO conversion rate of 96.5%, an IBO selectivity based on HPO standards of 87.2%, an IBυ conversion rate of 72.7%, and an IBO selectivity based on IBU standards of 98.5%. there were.

Incidentally, molybdenum dissolved in the reaction liquid obtained in this reaction after filtering and separating the catalyst was analyzed by atomic absorption spectrometry and found to be about 80 wtppm.

Example 3 In the same autoclave as in Example 1, 85 g of ethylbenzene and 15.3 g (0,273 mol) of metal molybdenum powder o, sg, and IBU were charged, and ethylbenzene containing 30-t% ethylbenzene hydroperoxide was prepared. After feeding 60.1 g (0.136 mol as HPO) of the solution over about 30 minutes, stirring was continued for 1 hour and the temperature was lowered.

Similar analysis revealed that the HPO conversion rate was 96.2%, and the HP
IBO selection rate based on O standard: 4%, IBU conversion rate: 42.
7%, and the 180 selectivity based on the 180 standard was 96.9%.

Example-4 In Example-1, isobutylene was replaced with trans
Example-11 except that -2-butene (hereinafter referred to as 2-iu) was used! -A similar reaction and analysis revealed that H
PO conversion rate 93.1%, HPO standard 2-butene oxide (hereinafter referred to as 2-BO) selectivity 87.3%, 2-80
Conversion rate 39.9%, 2-BO selectivity based on 2-B■ standard 98
．． It was 5%.

Example 5 In Example 2, the reaction and analysis were carried out in exactly the same manner as in Example 2, except that 2 g of metal molybdenum powder was used, and the molybdenum recovered by filtration, washing, and recovery from the resulting reaction liquid was used as a catalyst. The reaction was repeated five times.

The results are shown in Table 1.The surface of the molybdenum recovered after the completion of the five reactions was analyzed using XPS, and its oxidation state was investigated.The peak intensity ratio was 0%, 4%, 6%,
The pentavalent value was 26% and the hexavalent value was 48%.

Table 1 Unit [%] Comparative Example 1 In a 300 d four-way flask equipped with a thermometer, dropping funnel, and stirrer, 10.9 g of ammonium hebutamolybdate and 1001 d of water were dissolved. While stirring, an aqueous solution of 4.0 g of NaBHa dissolved in 1001M water was added dropwise from the dropping funnel over about 20 minutes to obtain a brown precipitate. After cooling, the supernatant liquid was decanted, and the precipitate, which was stirred and washed with degassed pure water, was further centrifuged and decanted, and this operation was repeated until the supernatant liquid became neutral. Thereafter, the mixture was replaced with 99% ethanol to avoid exposure to air, and further replaced with cumene. The precipitate obtained as above was sufficiently precipitated in cumene, and about 1 d was taken out with a pipette.
The reaction was carried out in the same manner as in Example 1 except that metal molybdenum powder was used as the catalyst, and analysis revealed that H
PO conversion rate 91.2%, IBO selectivity 6 based on IIPO standard
4.5%, 180 conversion rate 48.5%, IBU standard IB
The O selectivity was 58.6%. In addition, when the molybdenum precipitate was desolvated in vacuum and the oxidation state of the surface was examined by XPS, the peak intensity ratio was 26% for valence 4, 47% for valence 5,
The distribution was 27% with a valence of 6, and no surface with a valence of 0 was observed.

Comparative Example-2 All examples were the same except that 1.0 g of molybdenum trioxide (chemical reagent) was used as a catalyst instead of metal molybdenum powder.
When the reaction and analysis were carried out in the same manner as in 1, the HPO conversion rate was 98.2%, the IBO selectivity based on HPO was 2%, and the IBO conversion rate was 98.2%.
BU conversion rate 44.0%, IBO selectivity 8 based on IBIJ standards
It was 6.5%. Incidentally, molybdenum dissolved in the reaction solution obtained by this reaction was analyzed in the same manner as in Example 2, and was found to be about 60 wtppm.

Comparative Example-3 The reaction was carried out in the same manner as in Example-1 except that 0.1 g of molybdenum oxide acetylacetonate complex salt was used as a catalyst instead of the metal molybdenum powder, and analysis was performed.) IP
O conversion rate 94.1%, IBO selectivity based on IIPO standard 78
．． 2%, IBt1 conversion rate 43.5%, 180 standard IB
The O selection rate was 81.7%.

〔Effect of the invention〕

According to the present invention, butylene oxides can be produced extremely easily. Moreover, compared to conventionally known epoxidation methods, the desired product can be synthesized with a significantly higher selectivity at a molar ratio close to stoichiometric. The selectivity mentioned here is the one that is recognized for both the organic hydroperoxide and the raw material olefin compound having 4 carbon atoms. In addition, in the present invention, since the reaction is carried out under conditions in which molybdenum metal is not substantially dissolved, it is easy to recover expensive molybdenum metal, and there is almost no contamination of molybdenum compounds in the product, making it easy to purify the product. It is.

Claims (1)

[Claims] (1) When converting an olefinic compound having 4 carbon atoms into a corresponding epoxy compound using an organic hydroperoxide, the reaction is carried out in the presence of metallic molybdenum, which is substantially insoluble under the reaction conditions. A method for producing butylene oxide.