JPS6245572A - Production of 9-decalyl hydroperoxide - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a raw material for sebasic acid, etc., in a short time in high yield, by reacting decalin with oxygen, etc., in the presence of a specific amount of 1,1'-azobis-(cyclohexane-1-carbonitrile) based on decalin. CONSTITUTION:Decalin is brought into contact with oxygen or an oxygen- containing gas (e.g., air) and oxidized in the presence or absence of an alkali aqueous solution to give 9-decalyl hydroperoxide. The oxidation reaction is carried out in the presence of 0.01-5mol% based on decalin of 1,1'- azobis-(cyclohexane-1-carbonitrile). The reaction is carried out usually at 80-120 deg.C at normal pressure - 10kg/cm<2> in the presence of caustic soda as the alkali and emulsion oxidation is preferable in terms of industrial safety. Direct oxidation can be effected so the alkali is not necessarily required.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing 9-decaryl hydroperoxide.

9-Decalyl hydroperoxide is useful as a raw material for producing sebacic acid and the like, and it has been well known that the method for producing it involves contacting decalin with oxygen or an oxygen-containing gas to oxidize it.

However, in this method, an induction period is observed at the initial stage of oxidation, resulting in a long oxidation time, and as a result, more hydroperoxide groups are formed into carbinol groups.
There are problems such as a decrease in oxidation yield.

By the way, it has been known that addition of oxidation initiators such as corresponding alkylbenzene hydroperoxides, benzoyl peroxide, and azobisisobutyronitrile is effective for shortening the induction period in the oxidation of alkylbenzenes. In order to solve the above-mentioned problems in the oxidation reaction of decalin, the present inventors conducted various studies on various oxidation initiators in the same manner as in the oxidation of alkylbenzenes, and as a result, the oxidation reaction number ζ of decalin was determined. Therefore, only the azobis compound specified in the present invention is selectively effective in shortening the induction period, and also improves the oxidation rate, so the oxidation time is shortened, and as a result, the carboxylic acid of the produced 9-decaryl hydroperoxide is discovered that the yield of 9-decalyl hydroperoxide was improved by preventing the formation of
This invention has been achieved.

That is, in the present invention, when producing 9-decalyl hydroperoxide by contacting and oxidizing decalin with oxygen or an oxygen-containing gas in the presence or absence of an alkaline aqueous solution, 0.01 to 6 mol 1 of decalin is added to decalin. .1'
-Azobis-(cyclohexane-1-carbonitrile)
The present invention provides a method for producing 9-decalyl hydroperoxide, which is characterized by carrying out an oxidation reaction in the coexistence of 9-decalyl hydroperoxide.

In the present invention, the oxidation reaction itself is not particularly limited, and general oxidation reaction conditions may be used.

For example, the reaction temperature is usually selected to be in the range of 80 to 120°C, and oxygen or an oxygen-containing gas (typically air) is used as the oxidizing agent. The reaction pressure is usually normal pressure to 104/d.

The presence of an alkaline aqueous solution is not necessarily required in this oxidation reaction, and direct oxidation is possible, but in order to industrially safely obtain 9-decalyl hydroperoxide, the coexistence of an aqueous alkali solution (e.g., caustic soda, caustic potash) is necessary. It is desirable to emulsify and oxidize.

In this case, it is desirable to use 1/20 to IM times as much water as the organic phase, and to adjust the pH to a range of 10 to 5.

The reaction may be carried out in a batch manner or in a continuous manner, and is not particularly limited.

In the present invention, 1,1'-azobis-(cyclohexane-1-carbonitrile) is allowed to coexist in the oxidation reaction system in an amount of 0.01 to 6 mol, preferably 0.06 to 2 mol, based on the raw material decalin. is particularly important, and if the amount added is less than 0.01 mole relative to decalin, the effect will not be noticeable, and if it exceeds 5 mole, the effect commensurate with the amount added will not be obtained, so it is uneconomical. It is.

1.1'-Azobis-(cyclohexane-i-carbonitrile) may be added in its entirety at the start of the oxidation reaction, or may be added in portions or continuously depending on the consumption rate. The method is arbitrary.

Thus, according to the method of the present invention, excellent effects such as a short induction period in the oxidation reaction, a shortened oxidation time, and an improved yield of 9-decalyl hydroperoxide can be obtained.

The present invention will be explained below with reference to Examples.

Example 1 Decalin (86.7% trans form, 62.1% cis form)
Charge 0.51 of 15 (l and l, 1'-azobis-(cyclohexane-1-carbonitrile) into the reactor,
Warm to 4-96°C.

The oxidation reaction was carried out while stirring and constantly blowing oxygen into the liquid.

After the start of the reaction, the reaction solution was sampled at regular intervals, and decalin and 9-decalyl hydroperoxide (hereinafter referred to as
When the conversion rate, yield, and selectivity at each oxidation time were determined by analyzing DHPO, the results shown in Table 1 were obtained.

Comparative Example 1 An oxidation reaction was carried out in the same manner as in Example 1 except that DHPOl, 59 was added instead of 1.1-azobis-(cyclohexane-1-carbonitrile), and analyzed in the same manner to determine the results at each oxidation time. When the conversion rate, yield and selectivity were determined, the results shown in Table 1 were obtained.

Comparative Example 2 Same as Example 1 except that 2.2-azobis-isobutyronitrile 0.59 and DHPOl, 5y were added instead of 1.1-azobis-(cyclohexane-1-carbonitrile). An oxidation reaction was carried out and analysis was conducted in the same manner to determine the conversion rate, yield and selectivity at each oxidation time. The results are shown in Table 1.

Example 2 Decalin (86.7% trans form, 62.1% cis form)
15 (1) and 0.57 of 1.1'-azobis-(cyclohexane-1-carbonitrile) are charged into a reactor, 30 y of water is added, and the pH is adjusted to 8 with 1% caustic water.

Warm the reaction temperature to 94-96° C. with stirring.

Oxygen was constantly blown into the solution and 1% caustic water was added so that the pH was 8 during one reaction.

After the start of the reaction, samples were taken at regular intervals, and decalin and D)i PO in the oil layer after separation were analyzed to determine the conversion rate, yield, and selectivity at each oxidation time, as shown in Table 2. Got the results.

Table-1 Table-2

Claims (1)

[Claims] In producing 9-decalyl hydroperoxide by contacting and oxidizing decalin with oxygen or an oxygen-containing gas in the presence or absence of an alkaline aqueous solution, 0.01 to 5 mol% of 1,1'- A method for producing 9-decaryl hydroperoxide, which comprises carrying out an oxidation reaction in the coexistence of azobis-(cyclohexane-1-carbonitrile).