JPS6139935B2 - - Google Patents

Description

Detailed Description of the Invention The present invention provides 7-(5'-aminopentyl)-3,4,5,6-tetrahydro-
2H-azepine (hereinafter abbreviated as aminoschiff base ()), The present invention relates to an industrially advantageous method for producing 1,11-undecanediamine by catalytic hydrogen reduction.

1,11-Undecanediamine has important uses as a raw material for synthetic fibers, a raw material for synthetic resins, or as an intermediate for manufacturing various raw materials, so it is industrially advantageous and can be manufactured to obtain products of excellent quality. A method is desired.

Conventionally, the following methods are known as methods for obtaining 1,11-undecanediamine.

(1) A method for catalytic reduction of 1,11-diaminoundecene-4 or 5.

(2) A method of treating aminoschipf base () or its carbonate with hydrazine.

(3) A method of catalytic reduction of a mineral salt of amino Schipf base () using a platinum or rhodium catalyst in an acetic acid solvent containing an excess of mineral acid.

However, method (1) requires many steps to obtain starting materials, is complicated as an industrial process, and is economically disadvantageous. In addition, method (2) consumes a large amount of expensive hydrazine, so it cannot be an economically advantageous process. Furthermore, method (3) has drawbacks such as the yield of 1,11-undecanediamine which is still unsatisfactory from an industrial standpoint, and the reaction rate is also low, making it difficult to implement industrially. This is not an advantageous method.

An object of the present invention is to solve the problems of the prior art as described above and to provide an industrially advantageous method for producing 1,11-undecanediamine without requiring complicated operations. In order to achieve this objective, the present inventors have made intensive studies and found that an iridium-containing catalyst is used in the presence of an equimolar amount or more of water and an excess of hydrogen chloride to the amino Schiff base (2). The present invention was achieved based on the discovery that dramatically good results can be obtained in both reaction rate and selectivity by carrying out catalytic hydrogen reduction using the following methods.

Hydrogen chloride used in the present invention needs to be used in excess of the amount of amino Schiff base used as a starting material, and is usually at least the neutralizing equivalent amount relative to the amount of amino Schiff base () used, preferably neutralization equivalent. 1.2 times or more of the total equivalent amount, more preferably
It is desirable to use 1.5 times the amount or more.

Iridium-containing catalysts used in the present invention include iridium compounds such as iridium oxide, iridium hydroxide, iridium chloride, iridium nitrate, finely powdered metallic iridium such as iridium black, or iridium catalysts supported on various carriers. etc. can be used. Examples of the carrier include those commonly used as carriers, such as silica, activated carbon, alumina, silica/alumina, diatomaceous earth, titania, and barium sulfate. Further, alloys with other metals such as copper, silver, gold, and platinum metal elements, or multicomponent catalysts can be preferably used.

Amino Schiff base (), which is the starting material of the present invention, can be used to thermally decompose ε-caprolactam, ε-aminocaproic acid, or their oligomers or polymers in the presence of a base such as calcium oxide, calcium hydroxide, or lithium hydroxide. Therefore, it can be easily synthesized. This amino Schiff base ()
In the presence of water, forms an equilibrium system as shown in the following equation.

The method of the present invention must be carried out under reaction conditions that can form this equilibrium system, and the presence of water as well as amino Schiff base () is essential.

Usually, water is added to the amino Schiff base () in the reaction system.
It is desirable that it be present in an equimolar amount or more.

Amino Schiff base ( ) and bis(5-aminopentyl) ketone ( ), which are in an equilibrium relationship, are diacid base compounds having strong basicity, as is clear from their chemical structural formulas. Therefore, it forms salts with mineral acids such as sulfuric acid, hydrochloric acid, and phosphoric acid, and acidic compounds such as carboxylic acids. Many acidic compounds are isolated as ammonium salts of bis(5-aminopentyl)ketone (), while carbonic acid forms a mixture of carbamates represented by the following formula ().

When this carbamate () is made acidic with a strong acid such as hydrochloric acid in an aqueous solution, it generates carbon dioxide gas, forming a system that is essentially the same as the strong acid aqueous solution of aminoschizuf base (), and this system can be neutralized. It is possible to isolate the amino Schiff base () by: Therefore, the use of a salt of bis(5-aminopentyl) ketone () with an acidic compound or a carbamate () instead of the amino Schiff base () used as a starting material in the present invention essentially means that the amino Schiff base () is used as a starting material. It is obvious that this is the same as using () and is within the scope of the present invention. In addition, when using this or this compound as a starting material, these compounds already contain water equivalent to an equimolar amount to the amino Schiff base () in their molecules, so water must be added separately. Adding is not a mandatory requirement.

In the method of the present invention, a solvent is necessary to carry out the reaction in a liquid phase, but the solvent used is not particularly limited as long as it does not inhibit the reaction, and is usually water, acetic acid, propionate, etc. Although lower aliphatic carboxylic acids such as acids, alcohols, ethers, hydrocarbons, and halogenated hydrocarbons can be used, water and lower aliphatic carboxylic acids are preferably used.

The reaction format in the present invention is a batch method, a semi-continuous method, a semi-continuous method,
This can be carried out using a continuous method or other method. Any known method such as a solid bed or a fluidized bed can be preferably used for the catalyst. In addition, as for the reaction conditions, although hydrogen pressure is not particularly limited,
From the viewpoint of both reaction speed and pressure resistance of the equipment, it is usually 1 to 1.
A range of 300 atmospheres is used, more preferably a range of 5 to 150 atmospheres. Reaction temperature is usually 80-350℃
The temperature is preferably 100 to 250°C. As the reaction temperature decreases, the reaction rate decreases, and the formation of 1,11-diaminoundecanol-6(), which is a reaction intermediate, is observed.

According to the method of the present invention, in addition to 1,11-undecanediamine produced as the main product, 2-(5'-aminopentyl)-perhydroazepine () is produced as a by-product. In normal cases, the amount produced is 1・11− of the main product.
Compared to the amount of undecanediamine produced, only a small amount is produced.

The 1,11-undecanediamine produced by the method of the present invention can be extracted as a high-quality product through normal operations, for example, by combining operations such as neutralization, concentration, and extraction, or directly from the reaction system or by concentration. It can also be obtained by crystallizing 1,11-undecanediamine as a hydrochloride by diluting with a suitable solvent.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

Example 1 In a glass container with an internal volume of approximately 35 ml, 6 ml of 13 (weight)% hydrochloric acid, 1.0 g of aminoschizuf base () and 5%
Charge 200 mg of Ir/silica gel catalyst. A Teflon-coated magnetic rotor is placed in the container and a glass lid with a helical capillary for ventilation is placed. Place this container in an autoclave with an internal volume of 100ml, and after replacing the inside of the autoclave with hydrogen,
Pressurize to 50 atmospheres (gauge pressure) with hydrogen gas. This autoclave was placed in an oil bath at 150°C, and the contents were stirred with a magnetic stirrer to react for 4 hours. After the reaction is complete, remove the glass container and
After neutralizing the reaction mixture, 1,12-dodecanediamine was added as an internal standard substance, and gas chromatography (15% PEG + 4% KOH/Dia Solid UH, 3φ mm × 2.6 m, 210 °C, He 40 ml/m
In). As a result, no residual aminoschipf base () was observed, and the yield of 2-(5'-aminopentyl)-perhydroazepine was 1.1%.
The yield of 11-undecanediamine was 95%.

Example 2 By the same reaction procedure as in Example 1, 5 ml of glacial acetic acid saturated with hydrogen chloride gas, 0.5 ml of water, 5% Ir/
200 mg of a silica gel catalyst and 1.0 g of a carbamate represented by the formula in the main text of the specification were reacted for 4 hours under conditions of hydrogen (initial pressure) of 50 atm and 150°C. As a result, recovery of raw materials was not allowed, and 1.11
-It was confirmed by gas chromatography that undecane diamine was produced in 97% yield.

Claims (1)

[Claims] 1 7-(5'-aminopentyl)-3, 4, 5, 6
When producing 1,11-undecanediamine by catalytic hydrogen reduction using -tetrahydro-2H-azepine as a starting material, iridium is added to the starting material in the presence of an equimolar amount or more of water and an excess amount of hydrogen chloride. 1. A method for producing 1,11-undecanediamine, which comprises carrying out the reaction using a catalyst contained therein.