JPS5934694B2 - Method for producing 1,4-diacetoxy-cis-2-butene - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing 1,4-diacetoxycis-2-butene from butadiene.

There are various methods for synthesizing 1,4-butanediol, which has been in increasing demand in recent years as an organic solvent and raw material for synthetic resins. The currently industrialized method of producing acetylene using Retuppe reaction as a raw material has the drawbacks of a complicated reaction process and high raw material costs. In addition, the method of halogenating butadiene as a raw material to synthesize dihalogenated butene, esterifying it to synthesize diacetoxybutene, and hydrolyzing it with water to synthesize butanediol is the same as the Retzpe method. The disadvantages were that the process was complex and the cost of raw materials was high. The method that is currently considered most important industrially is to oxidize butadiene in one step in the presence of acetic acid to synthesize diacetoxybutene, which is then hydrolyzed with water to synthesize butanediol.

A gas phase method and a liquid phase method have been proposed as one-step synthesis methods for diacetoxybutene, but in the case of the gas phase method, there are problems such as generation of many by-products and catalyst life. Among the liquid phase methods for synthesizing diacetoxybutene, there are cases in which the catalyst is uniformly dissolved in the reaction liquid and cases in which a heterogeneous catalyst is used. The former is industrially disadvantageous because the catalyst separation and recovery steps become extremely complicated, whereas the latter is more advantageous. However, in the latter liquid phase reaction using a heterogeneous solid catalyst, the selectivity of the 1,4-diacetoxybutene produced is about 85%, with some by-products being produced, and 1,4-diacetoxybutene is a mixture of cis and trans forms, and has the disadvantage that a large amount of trans forms are produced, which is disadvantageous in the hydrogenation reaction in the next step. The present inventors have conducted intensive studies to overcome the drawbacks of these conventional methods, and as a result, the general composition is [Rh')xCP
OyCPd)z[Te)w(However, x■1, 2≦z(z
+y)≦3, 0.2≦w/(x+y+z)≦2.0) butadiene, acetic acid, and an oxygen-containing gas in the coexistence of a solid catalyst containing a metal (reduced compound containing the above metal component). The present invention was achieved based on the discovery that 1,4-diacetoxycis-2-butene can be obtained with a one-cut selectivity by reacting the above in a liquid phase. As a carrier for the catalyst used in the present invention, alumina, silica alumina, pumice, silica gel, synthetic zeolite, activated carbon, etc. can be used, and among them, silica gel and activated carbon are particularly excellent. Rhodium, platinum, palladium and tellurium compounds used as catalyst components include, for example, rhodium chloride, rhodium nitrate,
Rhodium sulfate, chloroplatinic acid, platinum chloride (platinum chloride QV)
), potassium platinum chloride (contains platinum potassium chloride (5), sodium chloroplatinate, palladium chloride, 1 cum palladium nitrate, sodium palladium chloride, palladium ammonium chloride, and tenoprotector chloride (5), teno dioxide VL/(
These include IV-containing tellurium trioxide (Vl), tenoprotective acid, orthotelluric acid, and the like.

The amount of noble metal component added to the carrier is 0.1 to 30 wtV
) is preferred, and most preferably 0.2 to 20 wt%. If the amount of these metal components added is small, such as 0.1 wt% or less, the reaction rate becomes extremely slow;
The above is economically disadvantageous. The mixing ratio of palladium or palladium and platinum to rhodium is 2 to 3 molar ratio. If the molar ratio exceeds 3, the selectivity for the cis isomer will be poor and the amount of the trans isomer and 3,4-diacetoxy-1-butene produced will increase, which is undesirable.If the molar ratio is less than 2, there will not be enough young fruit. The amount of tellurium added is 0.2 to 2.0 molar ratio to the total of rhodium and palladium (or rhodium, palladium, and platinum).

When the molar ratio is less than 0.2 or more than 2.0, the reaction rate slows down and at the same time 1,4-diacetoxysis
-It is not preferable because the selectivity of butene becomes poor. For example, the method for preparing the catalyst is as follows: (1) Dissolve the noble metal component compound and the tellurium compound in a suitable solvent, put the carrier therein and slowly evaporate to dryness while heating, and then
℃, and then reduced by a conventional method, that is, in a gas stream of hydrogen or methanol saturated vapor, or with a reducing agent such as hydrazine, NaBH4, formic acid, etc. (2) Noble metal component compound and tellurium compound Examples include a method in which a carrier is dissolved in a solvent, a carrier is added to impregnate the solution, and then the carrier is taken out, dried, and reduced. The catalyst used in the present invention can be used in various shapes depending on the type of reactor.

For example, when using a slurry method, fine powder is preferable, and when using a fixed bed method, granular form is preferable. The amount of catalyst used is preferably 0.2 to 30 wt%, most preferably 0.5 to 20 wt%, based on the total liquid amount.

When the amount of catalyst is less than 0.2 wt%, the reaction rate becomes very slow, and when the amount of catalyst is more than 30 wt%, by-products increase, which is not preferable. The amount of acetic acid used is preferably 3 to 100 moles, most preferably 5 to 50 moles, relative to the raw material butadiene. When the molar ratio is 3 or less, the reaction rate becomes slow and at the same time the selectivity decreases significantly. If the molar ratio is 100 times or more, separation of the target product after the reaction becomes uneconomical, which is industrially disadvantageous. The oxygen-containing gas used in the present invention may be pure oxygen or oxygen diluted with an inert gas, such as air. The amount of oxygen used is stoichiometric, i.e. 0 relative to the reacted butadiene.
．． It is sufficient that -E is present in an amount of 5 moles or more. The oxygen concentration is not particularly limited, but may be within a range that does not fall within the explosive range in the gas phase. The reaction temperature is preferably 30-200°C, most preferably 50-150°C.

If the reaction temperature is 30° C. or lower, the reaction rate will be very slow, making it uneconomical. A reaction temperature of 200° C. or higher is not preferable because the selectivity of 1,4-diacetoxy-12-butene becomes extremely poor. The reaction pressure is normal pressure to 1
00 atmospheres is preferred, and most preferably normal pressure to 50 atmospheres.

If the pressure is 100 atmospheres or more, it is unfavorable from the viewpoint of safety and economical aspects of the device. As described above, by the method of the present invention, 1,4-diacetoxysis-2-butene can be selectively obtained by reacting butadiene, acetic acid, and an oxygen-containing gas in the presence of a catalyst. It is very useful industrially.

The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to these Examples. In the Examples, the conversion rate is mol %, and the yield is mol % based on butadiene. Example 1 Rhodium chloride 0.15f7 (0.62mm01), palladium chloride 0.319V (1.79mm01), and tellurium dioxide 0.076t (0.48mm01) in 5N
The mixture was dissolved in 20 ml of hydrochloric acid, and 5 tons (16 to 32 mesh) of activated carbon that had been previously treated with nitric acid was placed therein and gradually evaporated to dryness on a hot water bath.

After that, this catalyst was packed in a calcining tube and heated at 150°C in a nitrogen stream for 1 hour.
After drying for an hour, the mixture was reduced at 200° C. for 2 hours using a methanol-nitrogen mixed gas saturated at room temperature, and then further reduced at 400° C. for 1 hour. This catalyst 0.10f was placed in a glass sealed tube with an internal volume of 25TI11, and 4.27 (70mm01) of acetic acid was placed on top of it.The glass sealed tube was cooled to the dry ice-methanol temperature, and the butadiene 108W ( After replacing the gas phase of the glass sealed tube with pure oxygen, the tube was sealed with a burner.

The reaction tube was allowed to react for 2 hours while rotating in a water bath at 80°C.

Analysis of the produced liquid by gas chromatography revealed that the conversion rate of butadiene was 56%, indicating that 1,4-diacetoxysis-2
-Yield of butene was 39.1%, 1,4-diacetoxy-
The yield of trans-2-butene is 10.591), 3,4
The yield of -diacetoxy-1-butene was 4.9%.

Example 2 Rhodium chloride 0.15f (0.62mm01), chloroplatinic acid 0.25t (0.49mm01), palladium chloride 0.15y (0.84mm01) and tellurium dioxide 0
．． 0761 (0.48mm01) in 5N monohydrochloric acid 20me
5 tons (1 ton) of activated carbon that had been previously treated with nitric acid was
6 to 32 meshes) were added and gradually evaporated to dryness on a hot water bath.

Thereafter, this catalyst was packed in a calcining tube and dried at 150°C in a nitrogen stream for 1 hour, then reduced at 200°C for 2 hours with a methanol-nitrogen mixture saturated at room temperature, and then further heated at 400°C for 1 hour. I got my time back. This catalyst 0.10V
The reaction was carried out in the same manner as in Example 1 using .

Analysis of the produced liquid by gas chromatography revealed that the conversion rate of butadiene was 62%, indicating that 1,4-diacetoxysis-2
-Yield of butene was 43.5%, 1,4-diacetoxy-
The yield of trans-2-butene was 10.9%, and the yield of 3,4-diacetoxy-1-butene was 5.1%.

Comparative Example 1 5N of palladium chloride 0.447 (2.47 mm01) and tellurium dioxide 0.0767 (0.48 mm01)
It was dissolved in 20 me of monohydrochloric acid, and 5 tons (16 to 32 mesh) of activated carbon that had been previously treated with nitric acid was placed therein and evaporated to dryness on a hot water bath.

Thereafter, the catalyst was packed in a calcining tube and dried at 150°C for 1 hour in a nitrogen stream, then reduced at 200°C for 2 hours with a methanol-nitrogen mixture saturated at room temperature, and then further heated at 400°C. It was allowed to recover for 1 hour. This catalyst 0.10
The reaction was carried out in the same manner as in Example 1 using 7.

Analysis of the product liquid by gas chromatography showed that the conversion rate of butadiene was 49 (fl), the yield of 1,4-diacetoxy-trans-2-butene was 15.9%, and the yield of 1,4-diacetoxy-trans-2 -butene yield is 27.3%, 3,
The yield of 4-diacetoxy-1-butene was 2.8%.

Comparative Example 2 Chloroplatinic acid 0.65V (1.27 dishes 01) and tellurium dioxide 0.076ft (0.48mm 01) were dissolved in 5N-hydrochloric acid 20d, and activated carbon 5V (16 to 32 dishes) which had been previously treated with nitric acid was dissolved in this solution. ) and was gradually evaporated to dryness on a hot water bath.

Thereafter, this catalyst was packed in a calcining tube and dried at 150°C in a nitrogen stream for 1 hour, then reduced at 200°C for 2 hours with a methanol-nitrogen mixture saturated at room temperature, and then further heated at 400°C for 1 hour. I got my time back. This catalyst 0.10V
The reaction was carried out in the same manner as in Example 1, and the resulting solution was analyzed by gas chromatography, and the conversion rate of butadiene was 65.
%, the yield of 1,4-diacetoxy-trans-2-butene was 10.1%, and the yield of 1,4-diacetoxy-trans-
The yield of 2-butene was 42.1%, and the yield of 3,4-diacetoxy-1-butene was 11.0%.

Claims (1)

[Claims] 1. General composition is [Rh]x[Pt]y[Pd] in molar ratio
z[Te]w (where x=1, 2≦z (or z+y)
≦3, 0.2≦w/(x+y+z)≦2.0) Butadiene and acetic acid at a temperature of 30 to 200°C in the presence of a solid catalyst (reduced compound containing the above metal component) containing a metal. 1. A method for producing 1,4-diacetoxy-cis-2-butene, which comprises reacting 1,4-diacetoxy-cis-2-butene with an oxygen-containing gas in a liquid phase.