JPH05186377A - Production of 1,6-hexanediol - Google Patents

Abstract

PURPOSE:To provide a new method for producing 1,6-hexanediol, the method being suitable for the industrial production of the 1,6-hexanediol. CONSTITUTION:1-Propen-3-al is dimerized in the presence of a dimerization catalyst comprising an organic VIII group metal compound to produce 2- hexene-1,6-dial, which is hydrogenated in the presence of a reduction catalyst into 1,6-hexanediol. The method passing through the 2-hexene-1,6-dial obtained by dimerizing the easily available 1-propen-3-al permits the profitable production of the 1,6-hexanediol.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel method for producing 1,6-hexanediol. 1,6-hexanediol is used as a raw material for synthetic polymers such as polyester and polyurethane, and also by reacting with ammonia in the presence of a metal catalyst and hydrogen, nylon 66
It is a very useful chemical intermediate, which is derived from 1,6-diaminohexane, which is a raw material for the above, and hexamethyleneimine, which is a raw material for agricultural chemicals.

[0002]

2. Description of the Related Art Conventionally, as an industrial method for producing 1,6-hexanediol, expensive adipic acid is esterified with a lower alcohol such as methanol to obtain adipic acid diester, which is copper-barium oxide-oxidized. A method of hydrocracking in the presence of a reducing catalyst such as chromium is generally used (US Pat. No. 3,268,588 etc.).

However, in this method, the reaction conditions for hydrocracking are severe at about 230 ° C. and 300 atm.
Desorption of alcohol by the esterification step-catalytic reduction step is not necessarily an economically advantageous method for producing 1,6-hexanediol because of high energy cost. On the other hand, 1-propen-3-al (acrolein), which is industrially produced on a large scale by air oxidation of propylene, can be produced inexpensively and has high reactivity, so it is an important intermediate of various organic compounds. It has been attracting attention for a long time as a body (for example, CWSmith, "Acrolei
n ", John Wiley & Sons, 1-27, 1962).

2-hexene-1,6-dial is 1,
It has been reported to be obtained by reacting 3-cyclooctadiene with ozone and dimethyl sulfide (T. Hudlicky et al., Journal of the American Chemic.
al Society, vol.110, p.4735 (1988)). However, in this method, an expensive raw material is used at an extremely low concentration and the reaction is performed at -78 ° C while controlling the ozone concentration, which is not desirable as an industrial production method.

Further, the dimerization reaction of 1-propen-3-al (acrolein) is carried out without a catalyst at 185-1.
By reacting at 95 ° C., 2,3-dihydro-2
-Formylpyran is known to be obtained (Japanese Patent Publication No. 40-9264). It has also been reported that the polymerization reaction proceeds by using a ruthenium compound as a catalyst (S. Komiya et al. Bulletin of the
Chemical Society of Japan, vol.48, 101 (1975))
However, there is no mention of dimer formation of 1-propen-3-al in this paper.

[0006]

An object of the present invention is to provide a novel method for producing 1,6-hexanediol suitable for industrial production.

[0007]

According to the present invention, 1-propen-3-al is reacted in the presence of a dimerization catalyst comprising an organic Group 8 metal compound to give 2-hexene-1,6-dial. , It was hydrogenated in the presence of a reducing catalyst to give 1,6-
Producing hexanediol 1,6-
It is a method for producing hexanediol.

(Raw material) The raw material 1-propen-3-al is industrially produced by air-oxidizing propylene in the gas phase in the presence of a metal oxide catalyst.

(Dimerization catalyst) In the production method of the present invention, 1
A catalyst is used for the dimerization of propen-3-al. As the dimerization catalyst, an organometallic compound containing at least one of Group 8 metal elements as a constituent component is used. The Group 8 metal is preferably one of iron, ruthenium and osmium, and more preferably ruthenium.

The Group 8 metal is preferably used as an organic metal compound soluble in the raw material. 8th
The organic group that coordinates or bonds to the group metal includes ethene,
Alkenes such as butene, butadiene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, 1,3-cyclooctadiene, 1,5-cyclooctadiene, 2,
Dienes such as 5-norbornadiene, trienes such as 1,3,5-cyclooctatriene, benzene, toluene, xylene, cumene, p-cymene, hexamethylbenzene, p-methoxybenzene, naphthalene, anthracene, benzonitrile, Examples include arenes such as anisole. The composition ratio of the organic group to the Group 8 metal is 1,000,000 or less, preferably 100,000 or less in terms of molar ratio.

Examples of organic Group 8 metal compounds include (η
-Cyclooctadiene) (η-cyclooctatriene)
Ruthenium, (η-benzene) (η-1,3-cyclohexadiene) ruthenium, bis (ethene) (η-hexamethylbenzene) ruthenium, (η-cyclooctadiene) (η-hexamethylbenzene) ruthenium, (η −
Benzene) (η-cyclooctadiene) ruthenium,
(Η-benzene) (η-norbornadiene) ruthenium, (η-cyclooctadiene) (η-1,3,5-trimethylbenzene) ruthenium, (η-norbornadiene) (η-1,3,5-trimethylbenzene) Ruthenium, (η-cyclooctadiene) (η-toluene) Ruthenium, (η-Cyclooctadiene) (η-xylene)
Ruthenium, (η-p-cymene) (η-cyclooctadiene) Ruthenium, (η-cyclooctadiene) (η-
p-methoxybenzene) ruthenium, (η-cyclooctadiene) (η-cycloheptatriene) ruthenium,
Examples include (η-cycloheptadiene) (η-cycloheptatriene) ruthenium, bis (cyclohexadienyl) ruthenium, and bis (hexamethylbenzene) ruthenium.

The dimerization catalyst can also be prepared by forming an organic Group 8 metal compound in the reaction system. The amount of the dimerization catalyst used is 1-propene-3 as the raw material.
-0.0000001 to 1 (molar ratio), preferably 0.000001 to 0.1 (molar ratio), relative to are
The range is. The dimerization catalyst is separated from the product of the dimerization reaction by a general method such as distillation and extraction and can be used repeatedly.

(Solvent for Dimerization Reaction) The dimerization reaction can be carried out without using a solvent, but if necessary, it is carried out in a suitable solvent which does not react with 1-propen-3-al. can do. Examples of these solvents include water; hydrocarbons such as hexane, benzene, and toluene; ethers such as diethyl ether, dimethoxyethane, tetrahydrofuran, and dioxane; esters such as ethyl acetate, butyl acetate, butyrolactone; dimethylformamide, Examples thereof include amides such as dimethylacetamide and N-methylpyrrolidinone; ureas such as dimethylimidazolidinone and tetramethylurea; alcohols such as isopropanol and t-butanol.
The concentration of 1-propen-3-al in these solvents is
It is 1% by weight or more, preferably 10% by weight or more.

(Dimerization Reaction Conditions) The dimerization reaction sufficiently proceeds even at room temperature, but it may be carried out under heating in order to further improve the reaction rate. Although the optimum reaction temperature varies depending on the pressure of hydrogen, it is generally 0 to 200 ° C,
It is preferably in the range of 20 to 150 ° C. The reaction pressure varies depending on the reaction temperature, but is generally in the range of 1 to 100 bar, preferably 5 to 50 bar. The reaction time varies depending on the reaction temperature, the catalyst concentration and the concentration of the raw materials, but is generally 0.1 to 200 hours, preferably 0.2 to 1
It is in the range of 00 hours.

The reaction can be carried out in air as long as the catalyst does not change, but it is generally carried out under a deoxygenated atmosphere,
Degas to a vacuum or replace with an inert gas such as nitrogen or argon or hydrogen. It is particularly preferable to carry out in the presence of hydrogen. In that case, the hydrogen pressure is generally in the range of 0.1 to 200 bar, preferably 0.5 to 100 bar, though it varies depending on other reaction conditions such as temperature.
The hydrogen used does not necessarily have to be of high purity, and substances that do not inhibit this reaction, such as nitrogen,
Argon, methane, etc. may be mixed with hydrogen at an arbitrary ratio and used.

(Product of Dimerization Reaction) 2-Hexene-1,6-dial is obtained by the above dimerization reaction.
At the same time, 2-methylenepentane-1,5-dial, which is an isomer of 2-hexene-1,6-dial, and
Oligomer of trimer or more of 1-propen-3-al may also be produced. The reaction mixture containing the catalyst is separated from the catalyst by a known method such as filtration, distillation, extraction, adsorption, etc. to separate 2-hexene-1,6-dial, and purified as necessary to obtain the next reduction / hydrogen. Subject to chemical reaction.

(Reduction catalyst) In the reduction reaction, a compound generally used as a catalyst for the hydrogenation reaction is used. Specific examples are Raney nickel; metallic nickel; supported nickel catalysts in which nickel is supported on a carrier such as diatomaceous earth, silica, alumina; CuO / Cr ₂ O ₃ , CuO / Cr ₂ O.
₃ / BaO, CuO / Cr ₂ O ₃ / MnO, CuO / C
Copper-chromium-based catalysts such as r ₂ O ₃ / MnO / BaO; Raney cobalt; Supported cobalt catalysts such as CoO / SiO ₂ , CoO / Al ₂ O ₃ ; Ru / carbon, Ru / Al ₂ O ₃ ,
Examples include ruthenium catalysts such as Ru / SiO ₂ + Al ₂ O ₃ and Ru / ZrO ₂ . The amount of reduction catalyst used is 2
-0.0 by weight ratio to hexene-1,6-diol.
The range is 0001 to 1, preferably 0.0001 to 0.1.

(Solvent for reduction reaction) The reduction reaction does not require a solvent, but if the need arises for controlling the heat of reaction, the reaction can be carried out in a suitable solvent. Specific examples of these solvents include water; aliphatic hydrocarbons such as hexane and octane; aromatic hydrocarbons such as benzene and toluene; methanol, ethanol, propanol,
Aliphatic alcohols such as butanol; ethers such as tetrahydrofuran and dioxane can be used, and 1,6-hexanediol, which is a target product, can also be used as a solvent. The amount of the solvent used was such that the concentration of 2-hexene-1,6-dial in the charged reaction solution was 0.
It is in the range of 1 to 100% by weight, preferably 1 to 90% by weight.

(Reduction reaction conditions) The reaction temperature of this reaction is 30
To 300 ° C, preferably 50 to 250 ° C.
The reaction pressure is 1 to 300 bar, preferably 5 to 200 bar.
It is in the bar range. You don't necessarily need to pressurize,
From the viewpoint of reaction efficiency, it is preferable to carry out the reaction under hydrogen pressure. Hydrogen may be diluted with nitrogen or the like before use. The reaction time varies depending on the reaction temperature, pressure, amount of catalyst, etc.
It is about 1 to 10 hours. As the reactor, a generally used reactor such as a complete mixing reactor or a fixed bed reactor can be used.

[0020]

Industrial Applicability According to the production method of the present invention, 1,6-propene-3-al is easily dimerized to obtain 2-hexene-1,6-dial.
-Hexanediol can be produced industrially advantageously.

[0021]

EXAMPLES Next, the present invention will be described more specifically by way of examples. In the examples, 2-hexene-1,6-dial was quantitatively analyzed by gas chromatography using an internal standard method using diethylene glycol diethyl ether as an internal standard substance, and the conversion rate and selectivity were determined by the following equations. Conversion rate (%) = 100 × (mol number of reacted raw material / mol number of charged raw material) Selectivity (%) = 100 × (mol number of target substance × 2 / mol number of reacted raw material)

<Example 1> In a Schlenk type flask, 228.7 mg (0.759 mmol) of (η-cyclooctadiene) (η-toluene) ruthenium was added to a Schlenk flask under a nitrogen stream.
8.8731 g (158.3 mmol) of 1-propen-3-al containing 1% by weight of hydroquinone and 0.534 g of diethylene glycol dimethyl ether as an internal standard substance for analyzing the reaction solution were charged. A stirrer was previously placed in a stainless steel autoclave having an inner volume of 30 ml to keep a nitrogen atmosphere, and the solution in the Schlenk type flask was transferred thereto. The inside of the system of this autoclave was replaced with hydrogen gas, hydrogen was introduced under pressure up to 5 bar, and then the reaction was carried out at 70 ° C. for 1 hour. As the reaction progressed, the reaction pressure dropped from 5.5 bar to 3.5 bar.

After completion of the reaction, the autoclave was opened and the contents were analyzed by gas chromatography.
-Propen-3-R 0.521g (2.29mmo
l), (Z) -2-hexene-1,6-dial 3.1
53 g (28.12 mmol), 2-methylene pentane-
0.15-mg (1.39 mmol) 1,5-Dial, 0.118 g (2.04 mmol) propanal, and 0.412 g (2.45 mm) trimer of 1-propen-3-al.
ol) was detected. In addition, oligomers of tetramer or higher of 1-propen-3-al were also produced.

The reaction solution obtained was subjected to vacuum distillation to obtain 0.8
A fraction of 2.8 g at 78 ° C. was captured in mmHg. Analysis by gas chromatography and NMR revealed that the content of (Z) -2-hexene-1,6-dial in this fraction was 9
It was 0%, and it was found that a small amount of trimer of 2-methylenepentane-1,5-diar and 1-propen-3-al was contained.

The conversion rate of 1-propen-3-al is 9
It was 4.1%, and the selectivity of (Z) -2-hexene-1,6-diary was 37.8%. In a Hastelloy autoclave having an internal volume of 40 ml, a stirrer, 1 g of the (Z) -2-hexene-1,6-dial fraction obtained above
(0 as (Z) -2-hexene-1,6-dial.
9 g (8.03 mmol)), CuO / Cr ₂ O ₃ / MnO
/0.5 g BaO catalyst and 5 ml dioxane as solvent
Was charged and sealed, and then the gas in the system was replaced with hydrogen. Further, hydrogen was injected under pressure up to 150 bar, and the reaction was carried out at 200 ° C. for 3 hours while heating and stirring the reactor.

After completion of the reaction, the reactor was opened, the catalyst was filtered off, and the reaction solution was analyzed by gas chromatography. As a result, the addition ratio of (Z) -2-hexene-1,6-dial was 100%, and the yield of 1,6-hexanediol was
It was 0.901 g (7.62 mmol) (yield 95 mol% based on (Z) -2-hexene-1,6-dial). When the solvent was distilled off under reduced pressure and the NMR spectrum of the residue was measured, it was in agreement with the spectrum of the authentic 1,6-hexanediol.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Naoko Sumitani 8-3-1 Chuo, Ami-machi, Inashiki-gun, Ibaraki Mitsubishi Petrochemical Co., Ltd. Tsukuba Research Institute

Claims (1)

[Claims] 1. The reaction of 1-propen-3-al in the presence of a dimerization catalyst comprising an organic Group 8 metal compound
A process for producing 1,6-hexanediol, which comprises producing hexene-1,6-dial and hydrogenating it in the presence of a reducing catalyst to produce 1,6-hexanediol.