JPH062705B2 - Process for producing 5-cyclodecen-1-one - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved process for preparing 5-cyclodecen-1-one.

5-Cyclodeten-1-one is an important compound as a raw material for the production of sebacic acid, etc.
A method is known in which 6-hydroxycyclodecanone is dehydrated by a gas phase method in the presence of a calcium sulfate catalyst and ammonia (BP 1,136,696).

However, this method is extremely difficult to use as an industrial production method because the catalyst activity is extremely deteriorated and the reaction cannot be continued for a long time.

From the above, the present inventors have conducted research to improve the drawbacks of the above-mentioned production method and industrially advantageously produce 5-cyclodecen-1-one. As a result, the sulfate used as a catalyst was previously prepared under specific conditions. It was found that the catalytic activity lasts for a long time, and as a result, 5-cyclodecen-1-one can be produced very advantageously, and the present invention has been accomplished.

That is, in the present invention, when 6-hydroxycyclodecanone is dehydrated by a gas phase method in the presence of a basic amine and a catalyst to produce 5-cyclodecen-1-one, the presence of an inert gas and a basic amine is previously determined. 260-3 below
260-320 ℃, using sulfate as a catalyst that is heat-treated at 20 ℃
5-cyclodecene-characterized in that dehydration reaction is carried out at
A method for producing 1-one is provided.

In the present invention, the sulfate used as the catalyst is preferably an alkaline earth metal salt of sulfuric acid, and most preferably magnesium sulfate and calcium sulfate.

Such a catalyst is used as an anhydride, and the size and shape of the particles are not particularly limited, but a particle size of about 5 to 100 mesh is preferable from the viewpoint of catalytic activity.

In the present invention, as the basic amine, ammonia, lower alkylamine (eg, primary amine such as methylamine, secondary amine such as diethylamine, tertiary amine such as triethylamine), heterocyclic amine (eg piperidine) is used. It

The pretreatment of the catalyst is carried out by treating the above-mentioned sulfate in the presence of the above basic amine and an inert gas (for example, nitrogen) at 260 to 320 ° C.
It is performed by heat treatment in.

Although the treatment method itself is not particularly limited, it is generally carried out by filling a sulfate and passing a basic amine and nitrogen through a reaction tube maintained at a predetermined temperature.

It is important that the treatment temperature is within the range of 260 to 320 ° C, and if it exceeds this range, sufficient effects cannot be obtained.

The processing time is appropriately determined according to each processing condition, but is generally 15 minutes or more.

The amount of the basic amine used for such pretreatment is usually 1 mmol or more, preferably 1 to 2 per 10 g of sulfate.
It is 0 mmol, and the amount of the inert gas used is not particularly limited as long as the treatment system is under an inert gas atmosphere.

Thus, the pretreatment of the catalyst is carried out, but generally, following this pretreatment, the dehydration reaction is carried out by the same reaction tube.

That is, the reaction is carried out by supplying 6-hydroxyclodecanone while continuously supplying the basic amine into the reaction tube filled with the catalyst after the pretreatment.

At this time, nitrogen or the like can be continuously supplied as the inert gas.

The reaction temperature during the dehydration reaction is preferably 260 to 320 ° C., and the amount of the basic amine used at this time is 6-
It is 0.01 to 0.3 mol times that of hydroxyclodecanone. If it is less than this range, the reaction does not proceed sufficiently, and even if it exceeds this range, it is economically disadvantageous because the effect equivalent to it cannot be obtained. Is.

The reaction is generally carried out at normal pressure, but it can also be carried out under reduced pressure.

Of course, the method of the present invention is not limited to the above-mentioned method, and may be another method, and the reaction method is not limited as long as it is a gas phase method. Further, the basic amine used for the pretreatment of the catalyst and the dehydration reaction are generally the same, but may be different depending on the case.

The raw material 6-hydroxycyclodecanone used in this reaction is not particularly limited in its production method. For example, it is produced by acid decomposition of 9-decalyl hydroperoxide. Since the presence of high-boiling impurities in the non-detrimentally affects the catalytic activity,
Prior to its use, it is preferable to remove high boiling impurities by distillation or the like in advance.

Thus, according to the method of the present invention, deterioration of the catalytic activity is very small, and 5-cyclodecen-1-one can be obtained in a good yield even in the reaction for a long time.

Hereinafter, the present invention will be described with reference to examples.

Example 1 10 g of anhydrous calcium sulfate having a particle size of 10 to 20 mesh
Is charged in a reaction tube, and nitrogen gas and ammonia are fed into the reaction tube at a rate of 150 ml / min and 2.4 ml / min, respectively, while heating. When the temperature reaches 300 ° C., this state is maintained for another 30 minutes to pretreat the catalyst.

While maintaining this state, 6-hydroxycyclodecanone obtained by acid decomposition of 9-decalylhydroperoxide (purity 92%, but high boiling point substances removed by distillation) was added at a rate of 5.5 g / Hr. Is further supplied to carry out the dehydration reaction.

After the dehydration reaction was started, the reaction products were analyzed for 30 minutes each of 9.5 to 10 hours, 49.5 to 50 hours, and 99.5 to 100 hours, and the 6-hydroxycyclodecanone conversion rate and 5-cyclodecene after each reaction time elapsed When the yield of -1-one was determined, the results shown in Table 1 were obtained.

Example 2 Pretreatment of catalyst and dehydration reaction were carried out in the same manner as in Example 1 except that monoisopropylamine was used in place of ammonia, and the supply rate thereof was 0.35 g / Hr. When the conversion rate of 6-hydroxycyclodecanone and the yield of 5-cyclodecen-1-one after the lapse of a predetermined reaction time were determined, the results shown in Table 1 were obtained.

Example 3 Pretreatment of a catalyst and dehydration reaction were carried out in the same manner as in Example 1 except that anhydrous magnesium sulfate was used instead of anhydrous calcium sulfate, and 6-hydroxycyclo after a predetermined reaction time was passed in the same manner as in Example 1. When the conversion rate of decanone and the yield of 5-cyclodecen-1-one were determined,
The results shown in Table-1 were obtained.

Comparative Example 1 10 g of anhydrous calcium sulfate having a particle size of 10 to 20 mesh
Is charged into a reaction tube and the temperature is raised to 300 ° C. Example 1
The same 6-hydroxycyclodecanone used in 1 above, nitrogen gas and ammonia were fed at a rate of 5.5 g / Hr, 150 ml / min and 2.4 ml / min, respectively, to carry out the dehydration reaction.

After the start of the reaction, the reaction products were analyzed for 30 minutes each of 1.5 to 2 hours, 3.5 to 4 hours, 9.5 to 10 hours, and 19.5 to 20 hours, and the conversion rate of 6-hydroxycyclodecanone after each reaction time elapsed. And 5-
When the yield of cyclodecen-1-one was determined, Table 1
The results shown in are obtained.

Claims (6)

[Claims] 1. 5-Hydroxycyclodecanone is dehydrated by a gas phase method in the presence of a basic amine and a catalyst to give 5-
Before producing cyclodecen-1-one, it was previously heated to 260 to 320 ° C. in the presence of an inert gas and a basic amine.
5-cyclodecene-1- characterized in that dehydration reaction is carried out at 260 to 320 ° C. using a sulfate salt obtained by heat treatment as a catalyst.
On manufacturing method. 2. The method according to claim 1, wherein the sulfate is an alkaline earth metal salt of sulfuric acid. 3. The method according to claim 1, wherein the alkaline earth metal salt of sulfuric acid is magnesium sulfate or calcium sulfate. 4. The production method according to claim 1, wherein the basic amine is ammonia, an alkylamine or a heterocyclic amine. 5. The production method according to claim 1, wherein the amount of the basic amine used for pretreatment of the catalyst is 1 to 20 mmol per 10 g of the catalyst. 6. The amount of the basic amine used in the dehydration reaction is 0.01 to 0.1 per mol of 6-hydroxycyclodecanone.
The method according to claim 1, wherein the amount is 3 mol.