JP2003286274A - Epoxidation method for olefin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently and safely epoxidizing an olefin with industrial advantage. <P>SOLUTION: A hydrogen peroxide aqueous solution is added to an olefin and carbonate salt including system under pressure whereby the olefin is epoxidized. <P>COPYRIGHT: (C)2004,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for epoxidizing an olefin under pressure using hydrogen peroxide and a carbonate. The epoxy compound obtained by the present invention is useful as an intermediate for agricultural chemicals and medicines and a raw material for various polymers. [0002] Conventionally, olefin epoxidation methods include (1) a method of epoxidation with a carboxylic acid such as acetic acid and hydrogen peroxide in the presence of an acidic catalyst such as sulfuric acid and salts such as sodium sulfate ( JP-A-5-32015
No. 0), (2) a method of epoxidation with hydrogen peroxide using methyl rhenium trioxide as a catalyst [Inorganic Chemistry (Inorganic)
Chemistry, Vol. 37, pp. 467-472 (1998)], (3) an aqueous phase in which tungstic acid, phosphoric acid and hydrogen peroxide are dissolved, and a water-insoluble solvent in which alicyclic olefins and onium salts are dissolved. Method for Epoxidation with a Heterogeneous System Consisting of Phases
Is known. However, in the method (1), a peracid such as formic acid generated in the reaction system has a high explosive property and has a problem in safety, and the epoxy compound reacts with the carboxylic acid present in the reaction system. As a result, an ester compound or the like is generated, and the selectivity of the target epoxy compound decreases. In the method (2), an expensive noble metal catalyst is used, and the hydrolysis reaction proceeds, and the epoxidation selectivity is low. In the method (3), hydrogen peroxide is decomposed by contact with tungstic acid, and oxygen is generated in the system, which is dangerous, and the efficiency of the epoxidation reaction per hydrogen peroxide is low. Further, the heavy metal catalyst such as the above-mentioned methyl rhenium trioxide or tungstic acid has a large burden on the environment, and the methods (2) and (3) are not preferable as an industrial production method. [0004] As an epoxidation method which has a small burden on the environment, (4) formation of an aqueous hydrogen carbonate solution and hydrogen peroxide using hydrogen peroxide in the presence of a large excess amount of an aqueous hydrogen carbonate solution with respect to the olefin; A method utilizing a catalytically active species has been proposed [Journal of American Society (J. Am. Chem. Soc.), Vol.
3220-3221 (2000)], it is pointed out that when an olefin hardly soluble in water is used, the presence of acetonitrile in the reaction system improves the reaction efficiency. [0005] In the above method (4), it has been confirmed by the present inventors that carbon dioxide gas volatilizes out of the system as the reaction proceeds, and the decomposition of hydrogen peroxide is performed. In order to suppress and increase the reaction rate, it is necessary to make an excess amount of hydrogen carbonate in the system relative to the olefin. However, bicarbonate can only be present in the system up to the amount at which the aqueous solution reaches a saturation concentration, and increasing the amount requires a larger amount of water to be present in the system. The concentration of the reaction substrate in the system becomes extremely low. In the case where acetonitrile is present in the reaction system in the method (4), when the extraction method is employed as a method for separating the epoxy compound from the reaction mixture after the reaction, the extraction efficiency is remarkably high depending on the extraction solvent. When the distillation method is employed, the hydrolysis reaction of acetonitrile proceeds by heating, and the separation / purification operation becomes difficult. Therefore, the method (4) is economically disadvantageous and is not preferable as a method for industrially epoxidizing olefins. It is an object of the present invention to provide an industrially advantageous process for epoxidizing olefins safely and efficiently. [0007] The present invention is a method for epoxidizing an olefin, which comprises adding an aqueous solution of hydrogen peroxide to a system in which an olefin and a carbonate are present under pressure. DETAILED DESCRIPTION OF THE INVENTION The olefin used in the present invention is represented by the following general formula (I): Wherein R ¹ , R ² , R ³ and R ⁴
Is a hydrogen atom, a halogen atom, an optionally substituted alkyl group, an optionally substituted aryl group, an optionally substituted alkenyl group having at least one carbon-carbon double bond, a nitro group, an alkoxyl group, a carbonyl group, an ester group or a carboxyl group or a salt thereof, or a plurality of these may form a cyclic structure together with the carbon atoms to which they are attached, R ^1, R ^{2, R 3} and ^R the total number of carbon ^{atoms 4} group represented by a is 2-18. Are preferred. In the general formula (I), R ¹ , R ² , R
The ³ and halogen atom represented by R ⁴ is, for example, a fluorine atom, a chlorine atom, a bromine atom. R ¹
As the alkyl group represented by R ² , R ^3, and R ⁴ , an alkyl group having 1 to 18 carbon atoms is preferable. For example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec group Linear alkyl groups such as -butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, cetyl group, stearyl group; cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloalkyl group; And cycloalkyl groups such as octyl group. These alkyl groups may have a substituent, as a substituent, for example,
A halogen atom such as a fluorine atom, a chlorine atom and a bromine atom;
Alkoxyl groups such as methoxy group, ethoxy group, propoxy group, isopropoxy group and butoxy group; nitro group; carboxyl group; alkoxycarbonyl group such as methoxycarbonyl group and ethoxycarbonyl group; acyl such as acetyl group, propionyl group and benzoyl group. Groups; ester groups such as an acetyloxy group and a propionyloxy group. The aryl group represented by R ¹ , R ² , R ³ and R ⁴ includes, for example, a phenyl group and a naphthyl group. These aryl groups may have a substituent. Examples of the substituent include a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom; a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group and a butoxy group. Alkoxyl groups such as nitro group; carboxyl group; alkoxycarbonyl groups such as methoxycarbonyl group and ethoxycarbonyl group; acyl groups such as acetyl group, propionyl group and benzoyl group; ester groups such as acetyloxy group and propionyloxy group. No. The alkenyl group having one or more carbon-carbon double bonds represented by R ¹ , R ² , R ³ and R ⁴ includes, for example, allyl group, methallyl group, prenyl group, 7-octenyl group, neryl group, A geranyl group;
These alkenyl groups may have a substituent, and examples of the substituent include a halogen atom such as a fluorine atom, a chlorine atom, and a bromine atom; a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a butoxy group. Nitro group; carboxyl group; alkoxycarbonyl group such as methoxycarbonyl group and ethoxycarbonyl group; acyl group such as acetyl group, propionyl group and benzoyl group; ester group such as acetyloxy group and propionyloxy group. Can be The alkoxyl groups represented by R ¹ , R ² , R ³ and R ⁴ include, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy and the like. An oxy group and a propionyloxy group are exemplified. R
Examples of the salt of the carboxyl group represented by ¹ , R ² , R ³ and R ⁴ include, for example, alkali metal salts such as sodium salt and potassium salt. When the number of carbon atoms represented by the general formula (I) is from 4 to
Examples of the olefin of 20 include 1-butene and 2-olefin.
Butene, 1-pentene, 2-pentene, 3-pentene,
Linear olefins such as 1-hexene, 2-hexene, 3-hexene, 1-heptene, 2-heptene and 3-heptene; 3,3-dimethyl-1-butene, 4-methyl-2
-Pentene, 2-methyl-2-pentene, 3-methyl-
2-pentene, 2,3-dimethyl-2-butene, 2,
4,4-trimethyl-2-pentene, 2-methyl-2-
Branched olefins such as heptene and 2,3,4-trimethyl-2-pentene; alcohol-containing olefins such as geraniol, nerol, linalool, citronellol, lavandulol, phytol and isophytol;
5-chloro-2-methyl-2-pentene, citronellyl bromide, citronellyl chloride, geranyl chloride,
Halogen-containing olefins such as geranyl bromide; ether-containing olefins such as diprenyl ether, diisoprenyl ether, and methylgeranyl ether; olefins containing ester groups such as geranyl acetate, neryl acetate, citronellyl acetate, lavandulyl acetate, and isophytolacetate Cyclopentene, cyclohexene, cycloheptene, cyclooctene, cyclododecene, 1-methyl-1-cyclohexene, 1-isopropyl-1-cyclohexene, 1,5-dimethyl-1-cyclooctene,
Cycloolefins such as pinene and norbornene; 2-cyclohexen-1-ol, 3-cyclohexene-1-
Alcohol-containing cycloolefins such as methanol and 5-norbornene-2-methanol; halogen-containing cycloolefins such as 1-chloro-3-cyclohexene and 1-chloro-5-cyclooctene; ether-containing such as 1-methoxy-3-cyclohexene Cycloolefin, 1
And ester group-containing cycloolefins such as -acetoxy-2-cyclohexene. The carbonate in the present invention includes a bicarbonate. Examples of the carbonate include alkali metal salts such as potassium carbonate, sodium carbonate, potassium hydrogen carbonate, and sodium hydrogen carbonate; ammonium carbonate, methyl ammonium carbonate, ethyl ammonium carbonate, propyl ammonium carbonate, butyl ammonium carbonate, dimethyl ammonium carbonate, and carbonic acid. Diethyl ammonium, trimethyl ammonium carbonate, triethyl ammonium carbonate, tetramethyl ammonium carbonate, tetrabutyl ammonium carbonate, ammonium bicarbonate, methyl ammonium bicarbonate, ethyl ammonium bicarbonate, propyl ammonium bicarbonate, butyl ammonium bicarbonate, dimethyl ammonium bicarbonate, Diethyl ammonium bicarbonate,
And ammonium salts such as trimethylammonium hydrogencarbonate, triethylammonium hydrogencarbonate, tetramethylammonium hydrogencarbonate and tetrabutylammonium hydrogencarbonate. These carbonates, even when used alone,
A mixture of more than one species may be used. The amount of the carbonate to be used is not particularly limited, but is preferably in the range of 0.01 to 10.0 mol, preferably 0.1 to 5.0 mol, per 1 mol of the double bond contained in the olefin from the viewpoint of reaction efficiency. More preferably, it is in the range of 0 mol. In the present invention, the carbonate may be prepared from a basic substance, water and carbon dioxide in the reaction system. Examples of the basic substance include sodium hydroxide,
Hydroxides of alkali metals such as potassium hydroxide; ammonia; methylamine, ethylamine, propylamine,
primary amines such as n-butylamine, n-octylamine, isopropylamine, isobutylamine and tert-butylamine; dimethylamine, diethylamine,
Secondary amines such as dibutylamine, pyrrolidine, piperidine, morpholine; tertiary amines such as trimethylamine, triethylamine, tributylamine, trioctylamine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine; pyridine, quinoline And aromatic amines such as quaternary ammonium hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide and tetra-n-butylammonium hydroxide. These basic substances may be used alone or in combination of two or more. The amount of the basic substance used is 0.01 to 1 mol per double bond contained in the olefin.
It is preferably in the range of 10.0 moles, and more preferably in the range of 0.1 to 5.0 moles from the viewpoint of reaction efficiency and volume efficiency. Carbon dioxide may be in any of a solid phase, a liquid phase and a gas phase. The aqueous hydrogen peroxide solution can be industrially easily obtained as a 10 to 60% by weight aqueous hydrogen peroxide solution.
Generally, a commercially available aqueous solution can be used as it is or after dilution with water. The concentration of hydrogen peroxide is not particularly limited, but from the viewpoint of safety, volumetric efficiency, etc.
It is preferably in the range of 01 to 60% by weight, and 0.1 to 60% by weight.
More preferably, it is in the range of 50% by weight. The amount of hydrogen peroxide to be used is preferably in the range of 0.1 to 10 mol per mol of double bond contained in the olefin, and from the viewpoint of reaction efficiency, selectivity and the like, it is preferably 0.5 to 5.0 mol. More preferably, it is in the range of 0 mol. The epoxidation reaction in the present invention is carried out under pressure. By performing under pressure, the volatilization of carbon dioxide generated by the reaction is suppressed. As a result, the amount of carbonate used is suppressed, the substrate concentration can be kept high, and the economic efficiency is improved. The pressure is not particularly limited.
It is preferably in the range of 9 KPa to 10.0 MPa,
More preferably, it is in the range of 0.1 MPa to 5.0 MPa. The gas used for pressurizing the system is not particularly limited as long as the reaction is not hindered, but in consideration of safety, carbon dioxide; an inert gas such as nitrogen or argon is used. Is preferred. The pressure vessel used in the present invention is preferably one that can be used in a pressure range of 0.1 MPa to 10.0 MPa. The material of the reaction vessel is preferably, for example, a metal material such as Harteloy, Inconel, or stainless steel; a glass material such as semicrystalline glass or Pyrex (registered trademark), and the inside is Teflon (registered trademark) or various polyamides. It is preferable to be coated with the above resin material. In particular, in consideration of the decomposition of hydrogen peroxide, it is preferable to use a reaction vessel made of glass and coated with Teflon (registered trademark), polyamide resin, or the like. In the present invention, the pH adjustment is not always necessary, but the pH can be adjusted as necessary in consideration of the suppression of decomposition of hydrogen peroxide, the reaction efficiency, the selectivity to the epoxy compound, and the like. When the pH is adjusted to an acidic side, for example, acids such as sulfuric acid, hydrochloric acid, and phosphoric acid or salts thereof are used. When the pH is adjusted to a basic side, for example, sodium hydroxide, potassium hydroxide, and calcium hydroxide are used. ,
Bases such as metal hydroxides such as magnesium hydroxide; carbonates such as sodium carbonate, potassium carbonate and ammonium carbonate are used. The pH of the reaction solution aqueous phase or the reaction mixture is preferably in the range of 6 to 10, and is preferably 6.5 to 6.5.
More preferably, it is in the range of 9.0. The amount of water used is not particularly limited, but from the viewpoint of volumetric efficiency, the concentration of the carbonate is adjusted so as to be in the range of 0.1% by weight to a saturated solution in the reaction mixture or the aqueous phase of the reaction solution at the reaction temperature. It is desirable to adjust. The present invention may be carried out in the presence of a solvent that does not inhibit the epoxidation reaction. Examples of the solvent include aliphatic hydrocarbons such as hexane, heptane and octane; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride and chlorobenzene; methyl acetate; Ethyl acetate,
Esters such as butyl acetate, methyl propionate and ethyl propionate; alcohols such as methanol, ethanol, isopropanol and t-butanol are used. It is preferable to use an alcohol such as methanol from the viewpoints of reaction efficiency and environmental load. The amount of the solvent used is preferably in the range of 0 to 100 times the weight of the olefin, more preferably in the range of 0 to 50 times the weight of the olefin, from the viewpoint of reactivity, volumetric efficiency and the like.
It is particularly preferred that the weight range is 0 times. The reaction temperature is not particularly limited, but is preferably in the range of 10 to 80 ° C., and in consideration of the range in which the rate of self-decomposition of hydrogen peroxide can be kept low, the reaction rate, etc. More preferably, it is in the range of 60 ° C. According to the present invention, for example, a
Charge water, olefin and, if necessary, reaction solvent,
After replacing the inside of the system with an inert gas, the reaction can be performed by adding an aqueous solution of hydrogen peroxide. From the viewpoint of safety, it is desirable to adopt a method of sequentially adding an aqueous solution of hydrogen peroxide to the reaction system. The epoxy compound thus obtained can be separated and obtained from the reaction mixture by a conventional method such as distillation. Prior to the distillation, the reaction mixture was subjected to sodium sulfite, potassium sulfite, ammonium sulfite, sodium bisulfite, potassium bisulfite,
It is desirable to treat with a reducing agent such as ammonium hydrogen sulfite, sodium thiosulfate or potassium thiosulfate. Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. Example 1 300 mL capacity equipped with thermometer, stirring shaft and stirring blade
100 g of water and 13.8 g (0.175 mol) of ammonium bicarbonate were added to a glass pressure-resistant container to prepare an aqueous solution of ammonium bicarbonate, and then 5.0 g of 3-methyl-3-buten-1-ol (58 .1mmo
l) was added and stirred to obtain a homogeneous solution. Next, the pressure in the system was adjusted to 0.3 MPa under a nitrogen atmosphere with stirring, and then the temperature was raised to 30 ° C. 16.9 g (173.9 mmol) of a 35% aqueous hydrogen peroxide solution was added to the system, and the mixture was stirred and reacted for about 6 hours. The resulting reaction mixture by gas chromatography (Shimadzu Corporation, GC-14B, Column: Chemicals Inspection Association Ltd., G-100,25m, carrier _{gas: He40ml / min, H 2 0.5kG} , A
ir 0.5 kG, 70-240 ° C., 5 ° C./min), the conversion of 3-methyl-3-buten-1-ol was 64%, and 3,4-epoxy-3-methylbutane-
It was confirmed that the selectivity of 1-ol was 62%. Example 2 300 mL capacity equipped with thermometer, stirring shaft and stirring blade
100 g of water and ethylamine 7.
9 g (0.176 mol) and 5.0 g (58.1 mol) of 3-methyl-3-buten-1-ol were added to prepare a homogeneous solution. The inside of the container was replaced with nitrogen and then carbon dioxide gas, and neutralized by vigorously stirring for about 1 hour in a carbon dioxide atmosphere, and then allowed to cool to an internal temperature of 25 ° C. The atmosphere in the vessel was replaced with nitrogen, the pressure was increased to 0.4 MPa, the temperature was raised to 30 ° C., and 16.9 g (173.9 mmol) of a 35% aqueous hydrogen peroxide solution was dropped into the system over about 10 minutes. The reaction was carried out with vigorous stirring for 6 hours. The resulting reaction solution was analyzed by gas chromatography (as described above), and the conversion of 3-methyl-3-buten-1-ol was 44% and 3,4-epoxy-3-methylbutane-
It was confirmed that the selectivity of 1-ol was 68%. Comparative Example 1 Capacity 20 with Thermometer and Mechanical Stirrer
100 g of water and 13.8 g (0.175 mol) of ammonium hydrogen carbonate were added to a 0 mL three-necked flask to prepare an aqueous solution of ammonium hydrogen carbonate. 5.0 g of 3-methyl-3-buten-1-ol (5 g
8.1 mmol), and the mixture was heated to 30 ° C. with stirring, and then 16.9 g of a 35% aqueous hydrogen peroxide solution (173.
9 mmol), and the mixture was stirred and reacted for about 6 hours. The resulting reaction solution was analyzed by gas chromatography (as described above). The conversion of 3-methyl-3-buten-1-ol was 36%, and 3,4-epoxy-3-methylbutan-1-ol was obtained. It was confirmed that the selectivity of all was 70%. According to the present invention, olefins can be safely
Epoxidation can be performed efficiently, and the corresponding epoxy compound can be industrially advantageously produced.

Claims (1)

Claims: 1. An olefin epoxidation method comprising adding an aqueous solution of hydrogen peroxide to a system in which an olefin and a carbonate are present, under pressure.