JPH0967337A - Production of arylalkyl hydroperoxide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject compound corresponding to the original compound in high selectivity and concentration by using an oxo metal compound as catalyst. SOLUTION: Using (A) an oxo metal compound as catalyst, (B) an arylalkyl hydrocarbon of formula (P and Q are each H or an alkyl; (n) is 1-3; Ar is an n-valent aromatic hydrocarbon)(e.g. cumene) is oxidized with an oxygen-contg. gas into the corresponding arylalkyl hydroperoxide. The component A is a compound of formula II (M is a metal; L is a ligand; (n) is 1-8), pref. an oxyvanadium compound, oxytitanium compound or oxyzirconium compound's salt or complex, for example, titanium (II) dioxide acetylacetonate.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to the oxidation of an arylalkyl hydrocarbon with an oxygen-containing gas using an oxometal compound as a catalyst to selectively and highly convert the corresponding arylalkylhydroperoxides. To a method for producing arylalkyl hydroperoxides.

[0002]

2. Description of the Related Art Various methods for producing corresponding arylalkyl hydroperoxides by oxidizing a hydrocarbon having an arylalkyl group with an oxygen-containing gas in the presence of a catalyst have been known.

For example, Japanese Examined Patent Publication No. 55-5020 discloses a water-soluble complex (chelate compound) of cobalt, nickel, manganese, copper or iron having a polyaminocarboxylic acid such as ethylenediaminetetraacetic acid (EDTA) as a ligand. Use as a catalyst to oxidize methylbenzenes having a secondary alkyl group such as 3,5-dimethylcumene with oxygen-containing gas in the presence of water to convert into corresponding hydroperoxides Is listed. However, using the above catalyst, the reaction cannot proceed at a practical speed in a temperature range of about 80 ° C.

[0004]

The present invention has been made to solve the above problems in the production of arylalkylhydroperoxides using a metal compound as a catalyst, wherein the oxo metal compound is an arylalkyl hydrocarbon. The present invention has been completed by discovering that it is a useful catalyst for conversion into the corresponding arylalkyl hydroperoxides by oxidizing in an oxygen-containing gas.

That is, an object of the present invention is to provide a method for producing a corresponding arylalkyl hydroperoxide by oxidizing an arylalkyl hydrocarbon with an oxygen-containing gas using an oxo metal compound as a catalyst. To do.

[0006]

The method for producing arylalkyl hydroperoxides according to the present invention uses an oxo metal compound as a catalyst in the general formula (I).

[0007]

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(In the formula, P and Q represent hydrogen or an alkyl group, which may be the same or different from each other, n is an integer of 1 to 3, and Ar is an n-valent aromatic. Group alkyl hydrocarbon group) is oxidized with an oxygen-containing gas to be converted into the corresponding arylalkyl hydroperoxides.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the method according to the present invention, the arylalkyl hydrocarbon used as a raw material has the general formula (I)

[0010]

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(In the formula, P and Q represent hydrogen or an alkyl group, which may be the same or different from each other, n is an integer of 1 to 3, and Ar is an n-valent aromatic. It represents a group hydrocarbon group.).

According to the present invention, the arylalkyl hydrocarbon represented by the above general formula (I) needs to have α hydrogen, and particularly preferably has tertiary hydrogen. Therefore, according to the present invention, in the above general formula (I), at least one of P and Q is preferably an alkyl group, and particularly preferably both are alkyl groups. As the above alkyl group, a methyl group is particularly preferable. Examples of the aromatic hydrocarbon group include an n-valent hydrocarbon group derived from benzene, naphthalene, biphenyl and the like, and an n-valent hydrocarbon group derived from benzene or naphthalene is preferable.

Therefore, in the present invention, preferred specific examples of the arylalkyl hydrocarbon include cumene, cymene, m-diisopropylbenzene, p-diisopropylbenzene, 1,3,5-triisopropylbenzene, isopropylnaphthalene and 2 Examples thereof include 6,6-diisopropylnaphthalene, isopropylbiphenyl, 4,4′-diisopropylbiphenyl, and a mixture of two or more thereof. However, it is not limited to these.

In the present invention, such an arylalkyl hydrocarbon is oxidized with an oxygen-containing gas using an oxo metal compound as a catalyst to selectively convert it into a corresponding arylalkylhydroperoxide. The oxo metal compound used in the present invention preferably has the general formula (II)

[0015]

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(Where M is a metal, L is a ligand, and n is 1 to 8).
Indicates an integer. ).

In the above general formula (II), M represents a metal, and specific examples thereof include, but are not limited to, vanadium, titanium and zirconium. L is a counter anion and /
Or a neutral ligand, as a preferred specific example, a halide ion, a sulfate ion, an acetylacetonate, an oxygen-containing compound such as crown ether, ethylenediamine, diethylenetriamine, triethylenetetramine,
Examples thereof include nitrogen-containing compounds such as phenanthroline, bipyridyl, and azacrown.

Specific preferred examples of such an oxo metal compound include titanium oxide (II) acetylacetonate, vanadium oxide (II) acetylacetonate,
Examples thereof include zirconium oxychloride. However, it is not limited to these. In general, as the oxo metal compound, a commercially available product may be used, or a compound synthesized by a conventionally known method may be used. For example, among the oxo metal compounds represented by the general formula (II), those having a neutral ligand are prepared by reacting an oxo metal compound such as vanadium (II) oxide acetylacetonate described above in a solvent. It can be easily obtained by treating with a ligand such as phenanthroline, bipyridyl or azacrown.

In the method of the present invention, the oxo metal compound may be used as a solid or may be dissolved in a reaction solution. Therefore, the reaction may be a heterogeneous reaction or a homogeneous reaction. In the method of the present invention, the oxo metal compound is usually used in the range of 0.00011 to 5.0 parts by weight, preferably 0. It is used in the range of 0001 to 0.1 part by weight.

Air is usually used as the oxygen-containing gas as the oxidizing agent. The reaction may be carried out under normal pressure, but may be carried out under pressure if necessary. The reaction temperature is usually in the range of 40 to 120 ° C, preferably 50 to 100 ° C.

According to the present invention, the reaction may be carried out in the presence of a basic compound. The basic compound is used as a solid or as an aqueous solution. For example, when using an aqueous alkaline solution, the reaction is carried out in a two-phase system. Examples of the basic compound include sodium carbonate, sodium hydrogen carbonate, sodium hydroxide, potassium carbonate, potassium hydrogen carbonate, potassium hydroxide, calcium hydroxide, barium oxide and the like. Such basic compounds are
It is usually used in an amount of 0.0001 to 10.0 parts by weight, preferably 0.001 to 5.0 parts by weight, based on 100 parts by weight of the starting arylalkyl hydrocarbon.

The reaction according to the present invention can be carried out batchwise or continuously. When the reaction is carried out in a batch system, if the starting arylalkyl hydrocarbon is a liquid at the reaction temperature, a catalyst is added thereto, and the air is usually blown into the mixture under heating and stirring to carry out the oxidation reaction. If necessary, an organic solvent or water inert to the reaction may be used as the reaction solvent. On the other hand, if the starting arylalkyl hydrocarbon is a solid at the reaction temperature, it is dissolved in an inert organic solvent to form a solution, a catalyst is added to the solution, and air is blown into the solution under heating and stirring to effect the oxidation reaction. You can do it.

Further, in the present invention, if necessary,
Upon initiation of the reaction, the arylalkyl hydrocarbon may have a corresponding small amount of arylalkylhydroperoxide present as an initiator. Alternatively, the catalyst may be formed in a fixed bed, and the arylalkyl hydrocarbon as a starting material or a solution thereof may be mixed with air and passed through the fixed bed.

According to the method of the present invention, the target arylalkyl hydroperoxide can be obtained by subjecting the reaction mixture obtained after the completion of the reaction to, if necessary, filtering off the catalyst, and then subjecting the obtained reaction mixture to conventional means such as distillation. It can be easily recovered from the reaction mixture.

[0025]

The present invention will be described below with reference to examples.
The present invention is not limited to these examples. The concentration of cumene hydroperoxide in the reaction mixture after completion of the reaction was determined by iodometry and gas chromatography. The selectivity of the cumene hydroperoxide produced was determined by gas chromatography.

Example 1 A mixture of 90 g of cumene and 10 g of cumene monohydroperoxide was added with 2 m of titanium (II) acetylacetonate.
g to 80 ° C. and add 180 m of air with stirring.
The cumene was air-oxidized at a rate of 1 / min for 6 hours. The concentration of cumene hydroperoxide in the reaction mixture after completion of the reaction was 16.9% by weight, and the accumulation rate of cumene hydroperoxide was 1.1% by weight / hour. Also,
The selectivity of the cumene hydroperoxide produced was 91%.

Comparative Example 1 Cumene was air-oxidized for 6 hours in the same manner as in Example 1 except that 20 mg of titanium (IV) oxide was used as the catalyst. As a result, the concentration of cumene hydroperoxide in the reaction mixture after completion of the reaction was 19.0% by weight.
The cumene hydroperoxide accumulation rate was 1.5% by weight / hour, but the selectivity of the cumene hydroperoxide produced was only 69%.

Example 2 Cumene was air-oxidized for 6 hours in the same manner as in Example 1 except that 5 mg of vanadium (II) oxide acetylacetonate was used as the catalyst. As a result, the cumene hydroperoxide accumulation rate was 3.0% by weight / hour, and the selectivity of the cumene hydroperoxide produced was 78%.

Example 3 Example 3 was repeated except that 2 mg of a complex of vanadium (II) oxide acetylacetonate coordinated with (1,4,8,11-tetraazacyclotetradecane) was used as the catalyst. Then, air oxidation of cumene was carried out for 6 hours. As a result, the cumene hydroperoxide accumulation rate was 1.5% by weight / hour, and the cumene hydroperoxide selectivity was 8%.
8%.

[0030]

As described above, according to the present invention, by using an oxo metal compound as a catalyst to oxidize an arylalkyl hydrocarbon with an oxygen-containing gas, the corresponding hydroperoxides can be obtained with high selectivity and high activity. It can be obtained in concentration.

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Claims (3)

[Claims] 1. An oxo metal compound as a catalyst, represented by the general formula (I): (In the formula, P and Q represent hydrogen or an alkyl group, which may be the same or different from each other, and n is 1 to 1).
3 represents an integer of 3, and Ar represents an n-valent aromatic hydrocarbon group. ) An arylalkyl hydrocarbon represented by the formula (3) is oxidized with an oxygen-containing gas to be converted into the corresponding arylalkylhydroperoxides. 2. An oxo metal compound is represented by the general formula (II): The method according to claim 1, wherein the compound is a compound represented by the formula (M is a metal, L is a ligand, and n is an integer of 1 to 8.). 3. The method according to claim 1, wherein the oxo metal compound is a salt or complex of an oxyvanadium compound, an oxytitanium compound, an oxyzirconium compound.