JPH08245568A - Method for producing arylalkyl hydroperoxides - Google Patents

Abstract

(57) [Summary] [Purpose] Oxidation of arylalkyl hydrocarbons with oxygen-containing gas using certain transition metal complex salts as catalysts,
It is to provide a method for producing the corresponding arylalkyl hydroperoxides. The method for producing arylalkyl hydroperoxides according to the present invention comprises the following formula (I): M ² m [M ¹ Xn] (wherein M ¹ is iron, manganese, cobalt, copper, ruthenium, nickel or rhodium). And a cation of a transition metal selected from platinum, X represents an anion selected from a cyan ion, a thiocyan ion and a halide ion, and M ² is selected from an alkali metal, an alkaline earth metal and tetraalkylammonium. Shows cations,
n shows the integer of 1-10, m shows the integer of 0-5. ), In the presence of a transition metal complex salt catalyst represented by the formula (1), an arylalkyl hydrocarbon having α hydrogen is oxidized with an oxygen-containing gas and selectively converted into a corresponding arylalkylhydroperoxide. The transition metal complex salt, for example, potassium ferrocyanide,
Examples thereof include potassium ferricyanide and sodium ferricyanide.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention uses a transition metal complex salt as a catalyst to oxidize an arylalkyl hydrocarbon with an oxygen-containing gas to selectively and highly convert it into a corresponding arylalkylhydroperoxide. To a method for producing arylalkyl hydroperoxides.

[0002]

2. Description of the Related Art Various methods for producing a corresponding arylalkyl hydroperoxide by oxidizing a hydrocarbon having an arylalkyl group with an oxygen-containing gas in the presence of a catalyst are conventionally known. For example, Japanese Patent Publication Sho 55-5
Japanese Patent No. 0020 discloses that ethylenediaminetetraacetic acid (EDT
Using a water-soluble complex (chelate compound) of cobalt, nickel, manganese, copper or iron having a polyaminocarboxylic acid such as A) as a ligand as a catalyst, the presence of
-A method is described in which an arylalkyl hydrocarbon having a secondary alkyl group such as dimethylcumene is oxidized with an oxygen-containing gas and converted to the corresponding hydroperoxides.

However, according to this method, the oxidation reaction cannot proceed at a practical oxidation rate under relatively mild reaction conditions.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art method of oxidizing arylalkyl hydrocarbons with an oxygen-containing gas to produce the corresponding arylalkylhydroperoxides. The inventors have found that certain transition metal complex salts are useful catalysts for the oxidation of arylalkyl hydrocarbons with oxygen-containing gases and conversion to the corresponding arylalkylhydroperoxides. It was the invention.

That is, the present invention provides a method for producing corresponding arylalkyl hydroperoxides by oxidizing an arylalkyl hydrocarbon with an oxygen-containing gas by using a certain transition metal complex salt as a catalyst. With the goal.

[0006]

The method for producing arylalkyl hydroperoxides according to the present invention comprises the following formula (I): M ² m [M ¹ Xn] (wherein M ¹ is iron, manganese, cobalt or copper). , Cations of a transition metal selected from ruthenium, nickel, rhodium and platinum, X represents an anion selected from cyanide ion, thiocyanate and halide ion, M ² represents an alkali metal, alkaline earth metal and Indicates a cation selected from tetraalkylammonium,
n shows the integer of 1-10, m shows the integer of 0-5. ) In the presence of a transition metal complex salt catalyst represented by the general formula (II)

[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, x represents an integer of 1 to 3, and Ar represents an aromatic valence of x. A group represented by a group hydrocarbon group) is oxidized with an oxygen-containing gas and selectively converted into the corresponding arylalkyl hydroperoxides.

In the method according to the present invention, the arylalkyl hydrocarbon used as a raw material has the general formula (II)

[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, x is an integer of 1 to 3, and Ar is an x-valent fragrance. 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 x-valent hydrocarbon group derived from benzene, naphthalene, biphenyl, diphenyl ether, etc., and an x-valent hydrocarbon group derived from benzene or naphthalene is preferable. .

Therefore, in the present invention, preferable specific examples of the arylalkyl hydrocarbon include diisopropylbenzenes such as cumene, cymen, m-diisopropylbenzene and p-diisopropylbenzene, 1,
Triisopropylbenzenes such as 3,5-triisopropylbenzene, ethylbenzene, sec-butylbenzene, sec-butylethylbenzene, isopropylnaphthalenes, diisopropylnaphthalenes such as 2,6-diisopropylnaphthalene, isopropylbiphenyls, 4,
Examples thereof include diisopropyl biphenyls such as 4′-diisopropyl biphenyl, and mixtures of two or more thereof. However, it is not limited to these.

In the present invention, a certain kind of transition metal complex salt is used as a catalyst to oxidize an arylalkyl hydrocarbon as described above with an oxygen-containing gas to selectively convert it into a corresponding arylalkylhydroperoxide. To do.

The transition metal complex salt used in the present invention is represented by the general formula (I) M ² m [M ¹ Xn] (wherein M ¹ is selected from iron, manganese, cobalt, copper, ruthenium, nickel, rhodium and platinum). Represents a cation of a transition metal, X represents an anion selected from cyanide, thiocyanate and halide, M ² represents a cation selected from alkali metal, alkaline earth metal and tetraalkylammonium. ,
n shows the integer of 1-10, m shows the integer of 0-5. ).

In the above general formula (I), examples of the halide ion include chlorine ion and bromine ion. Examples of the alkali metal include lithium, potassium and sodium, and examples of the alkaline earth metal include calcium, strontium and barium. Further, examples of the tetraalkylammonium include tetramethylammonium, tetraethylammonium, tetrabutylammonium and the like.

Accordingly, specific examples of such a transition metal complex salt include potassium salts such as potassium hexacyanoferrate (II) (potassium ferrocyanide), potassium hexacyanoferrate (III) (potassium ferricyanide), and the like. Potassium pentacyanoammine iron (II), potassium pentacyanoammine iron (III), potassium pentacyanonitrosyl iron (II), potassium pentacyanonitrosyl iron (III), potassium hexakis (thiocyanato) iron (II) Hexakis (thiocyanato)
Potassium iron (III), potassium hexafluorocobalt (III), potassium tetrachlorocobalt (II), potassium trifluoromanganate (II), potassium hexafluoromanganate (IV), potassium pentachloromanganese (III) , Potassium hexachloromanganate (IV), potassium hexacyanomanganate (II), potassium hexacyanomanganate (III), pentacyanonitrosyl (I
I) Potassium, pentachloroaquarthenium (III)
Acid potassium, potassium hexacyanoruthenium (II) acid, potassium hexachlororhodium (III) acid, potassium hexacyanorhodium (III) acid, potassium hexabromoplatinate (IV) acid, potassium tetracyanonickel (II) acid, tetrafluoronickel (II) Examples thereof include potassium acid salt, potassium tetrachloronickelate (II), potassium tetrabromonickelate (II) and the like.

Further, according to the present invention, as the transition metal complex salt, a sodium salt corresponding to the above potassium salt, for example,
Examples thereof include sodium hexacyanoferrate (III) (sodium ferricyanide) and tetraalkylammonium salts such as tetramethylammonium salt, tetraethylammonium salt and tetrabutylammonium salt.

Particularly in the present invention, it is preferable to use iron, cobalt or ruthenium complex salt as a catalyst.

As these transition metal complex salts, commercially available products may be used as they are as catalysts, or if necessary, recrystallization,
It may be used as a catalyst after being subjected to usual purification such as crystallization. Further, if necessary, a complex salt may be synthesized from an inorganic salt of a transition metal by a conventionally known ordinary method.

In the method of the present invention, the above transition metal complex salt may be used as a solid as it is, or may be dissolved in a reaction system, especially water, and used. Therefore, the reaction can be carried out in either a heterogeneous reaction or a homogeneous reaction. In the present invention, the transition metal complex salt is usually used in the range of 0.0001 to 5.0 parts by weight based on 100 parts by weight of the starting arylalkyl hydrocarbon.
It is preferably used in the range of 0.0001 to 0.1 part by weight.

Air is usually used as the oxygen-containing gas as the oxidizing agent, but oxygen or an arbitrary mixed gas of oxygen and nitrogen may be used. 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.

Further, according to the present invention, the reaction may be carried out in the presence of a solid basic compound or an aqueous solution of a basic compound. Specific examples of the basic compound include, for example,
Examples thereof include sodium carbonate, sodium hydrogen carbonate, sodium hydroxide, potassium carbonate, potassium hydrogen carbonate, potassium hydroxide, barium oxide and magnesium oxide. These basic compounds are added in an amount of 0.000 based on 100 parts by weight of the starting arylalkyl hydrocarbon.
It is used in the range of from 01 to 10.0 parts by weight, and preferably 0.1.
It is used in the range of 001 to 5.0 parts by weight.

In the present invention, the reaction 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,
The solution may be dissolved in an organic solvent inert to the reaction to form a solution, a catalyst may be added thereto, and air may be blown into the solution under heating and stirring to carry out the oxidation reaction.

Further, in the present invention, if necessary,
At the start of the reaction, a small amount of the corresponding arylalkyl hydroperoxide or the like may be present as an initiator in the arylalkyl hydrocarbon. 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 easily recovered from the reaction mixture by a usual means such as distillation of the obtained reaction mixture after completion of the reaction.

[0027]

The present invention will be described below with reference to examples.
The present invention is not limited to these examples. In the following, 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 1 200 mg of potassium hexacyanoferrate (III) in a mixture of 90 g of cumene and 10 g of cumene monohydroperoxide.
And 10 ml of water were added and the mixture was heated to 80 ° C., and air was blown into the mixture at a rate of 60 ml / min with stirring to air-oxidize cumene for 7 hours. The concentration of cumene hydroperoxide in the reaction mixture after the completion of the reaction was 24.2% by weight, and the accumulation rate of cumene hydroperoxide in the meantime was 2.0% by weight / hour. Further, the selectivity of the cumene hydroperoxide produced was 83%.

Example 2 In Example 1, potassium hexacyanoferrate (III) 2
Instead of 00 mg, potassium hexacyanoferrate (II) 2
The oxidation reaction was carried out in the same manner as in Example 1 except that 00 mgl was used. As a result, the cumene hydroperoxide accumulation rate was 2.2% by weight / hour, and the selectivity of the cumene hydroperoxide produced was 84%.

Example 3 In Example 1, potassium hexacyanoferrate (III) 2
The oxidation reaction was carried out in the same manner as in Example 1 except that 200 mgl of potassium hexacyanocobaltate (III) was used instead of 00 mg. As a result, the cumene hydroperoxide accumulation rate was 0.9% by weight / hour, and the cumene hydroperoxide selectivity was 93%.
%Met.

Comparative Example 1 In Example 1, potassium hexacyanoferrate (III) 2
Na ₂ [Co (EDTA)] 200 instead of 00 mg
The reaction was performed in the same manner as in Example 1 except that mg was used as the catalyst. The concentration of cumene hydroperoxide in the reaction mixture after the reaction was 11.0% by weight. The selectivity of cumene hydroperoxide produced is 64.
%Met. By-products of acetophenone, dimethylphenylcarbinol and dicumyl peroxide were observed.

[0032]

As described above, according to the present invention, by using a certain transition metal complex salt such as potassium ferricyanide as a catalyst, an arylalkyl hydrocarbon is oxidized by an oxygen-containing gas, and Corresponding hydroperoxides can be obtained with high reaction rate and high selectivity under mild reaction conditions.

Claims (5)

[Claims] 1. General formula (I) M ² m [M ¹ Xn] (wherein M ¹ is a cation of a transition metal selected from iron, manganese, cobalt, copper, ruthenium, nickel, rhodium and platinum). X represents an anion selected from cyanide, thiocyanate and halide, M ² represents a cation selected from alkali metal, alkaline earth metal and tetraalkylammonium,
n shows the integer of 1-10, m shows the integer of 0-5. ) In the presence of a transition metal complex salt catalyst represented by the general formula (II) (In the formula, P and Q represent hydrogen or an alkyl group, which may be the same or different from each other, and x is 1 to
3 represents an integer of 3 and Ar represents an x-valent aromatic hydrocarbon group. ) The arylalkyl hydrocarbon represented by the formula (3) is oxidized with an oxygen-containing gas to selectively convert it into the corresponding arylalkylhydroperoxides. 2. The method according to claim 1, wherein X is a cyan ion. 3. The method according to claim 1, wherein the transition metal complex salt is an iron, cobalt or ruthenium complex salt. 4. The method according to claim 1, wherein the transition metal complex salt is potassium ferrocyanide or potassium ferricyanide. 5. The method according to claim 1, wherein the arylalkyl hydrocarbon is oxidized with an oxygen-containing gas in the presence of a basic compound.