JPH01100139A - Production of 3-methylpentane-1,5-diol - Google Patents

Abstract

PURPOSE:To obtain the titled compound in high selectivity at a low cost, by hydrogenating 2-hydroxy-4-methyltetrahydropyran in the presence of a hydrogenation catalyst consisting of a molybdenum-modified Raney-Ni catalyst. CONSTITUTION:The titled compound useful as a raw material for polyester polyol can be produced by hydrogenating 2-hydroxy-4-methyltetrahydropyran in the presence of 0.1-10wt.%, preferably 0.5-5wt.% (in terms of metal based on the reaction mixture) of a molybdenum-modified Raney-Ni catalyst (preferably a catalyst modified with 0.1-10wt.% of molybdenum based on nickel) at 1-100atm., preferably 2-20atm., especially 5-15atm. at 50-180 deg.C, preferably 80-140 deg.C preferably using the reaction product as a reaction solvent. The industrial advantages of the process are e.g. quantitative production of the objective compound even under low pressure condition, the repeated use of the catalyst with little lowering of the catalytic activity, etc.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to hydrogenation of 3-methylpentane-1,5-diol (hereinafter referred to as MPi) by hydrogenation of 2-hydroxy-4-methyltetrahydrobilane (hereinafter referred to as MHP). )) is related to an improved manufacturing method.

The MPD obtained by the method of the present invention is useful as a raw material for polyester polyols. Since polyester polyol is liquid and has excellent physical properties such as hydrolysis resistance, it is possible to take advantage of its properties by using it in the fields of polyurethane and polymer plasticizers.

[Conventional technology]

Conventionally, as a method for producing MPI, a method is known in which MKP is hydrogenated in the presence of a hydrogenation catalyst at elevated temperature and pressure (Japanese Patent Publication No. 40533/1983). In Publication No. 40533, MPD is specifically produced by hydrogenating M)IP in the presence of a Raney cobalt catalyst under a pressure of 200 atmospheres. The publication also mentions that catalysts containing cobalt and nickel, which may contain activating additives such as copper, chromium, and manganese, are preferable to ordinary hydrogenation catalysts, or provide specific examples. is not disclosed.

[Problem that the invention seeks to solve] When MILP is hydrogenated according to conventionally known methods.

Significant amounts of β-methyl-δ-valerolactone and MI
An acetalization reaction product of IP and MPD is produced as a by-product. These by-products not only reduce the selectivity to KPD but also degrade the hydrogenation catalyst.

Among these, it is an industrially serious problem that when a hydrogenation catalyst is used repeatedly, its activity decreases rapidly the second time. Hydrogenation catalysts are relatively expensive;
The amount used in the hydrogenation reaction is large, and when producing a general-purpose chemical product like the one of the present invention, it cannot be said that it is an economical production method unless it can be used repeatedly.

Therefore, an object of the present invention is to find a hydrogenation catalyst that can obtain a high selectivity to AIFD in the MnP hydrogenation reaction and can be used repeatedly over a long period of time.

[Means for solving problems]

The inventors of the present invention have made extensive studies and have discovered that the above object can be achieved by using molybdenum-modified Raney nickel as a catalyst in the hydrogenation reaction of MHP, leading to the present invention. That is, the present invention uses a molybdenum-modified Raney nickel catalyst as a catalyst when hydrogenating 2-hydroxy-4-methyltetrahydropyran in the presence of a hydrogenation catalyst to produce 3-methylpentane-1,5-diol. 3-methylpentane-1, characterized by
This is a method for producing 5-diol.

By using molybdenum-modified Raney nickel as a hydrogenation catalyst for MiiP, it is possible to produce MPD%li almost quantitatively even at low pressure from Mill', and the activity hardly decreases even after repeated use, which is a great industrial advantage. brought about. As is clear from the comparative examples described later, such effects are not produced by commonly used hydrogenation catalysts such as Raney nickel, stabilized nickel, Raney cobalt, and copper chromite catalysts.

In the present invention, it is necessary to use a Raney nickel catalyst modified with molybdenum as a hydrogenation catalyst for MfiP. If the proportion of modification by molybdenum is too small, the above effect will be small, and if the proportion of modification is too large, the preparation tends to be complicated. Preference is given to using catalysts modified with %0 molybdenum. Since such a modified catalyst is easily available as modified Raney nickel, it is preferred from this point of view as well. In the present invention, in addition to molybdenum, small amounts of metals such as d, (3u, Co
Even if it contains %W, TOlZn, etc. within a range that does not cause actual harm, there is no problem.

The molybdenum-modified Raney nickel catalyst is 0.1 to 10% by weight, preferably 0.1 to 10% by weight in terms of metal weight, based on the reaction mixture.
Preferably, it is used in an amount of 5 to 5% by weight. The molybdenum-modified Raney nickel catalyst can be used alone or supported on a carrier such as alumina, silica, diatomaceous earth, or the like.

If the hydrogenation reaction of MIiP is carried out under hydrogen pressure or the pressure of the hydrogenation reaction is too low, the concentration of unreacted raw materials will increase with the same amount of raw material supplied, and as a result the catalyst will tend to deteriorate. In addition, even if fh is higher, it will not be as effective and problems will occur on the equipment, so in the present invention, it is carried out at 1 to 100 atm, preferably 2 to 20 atm, more preferably 5 to 15 atm. is desirable.

If the temperature of hydrogenation reaction of M n P is too low, the reaction rate tends to be low, and even if it is too high, the effect will not be as great. It will not be implemented.

A solvent inert to the reaction is used in the hydrogenation reaction of MILF, and specific examples of such solvents are as follows.

Examples include alcohols such as methanol, ethanol, butanol, and 2-ethylhexanol, and ethers such as dibutyl ether, dioxane, and tetrahydrofuran. Since the solvent is separated from the reaction product and reused, it is preferable to use the reaction product as the solvent in order to avoid the complexity of separation.

The hydrogenation reaction of MllP can be carried out batchwise or continuously using a suspended bed, fixed bed, etc. reaction system.
It is preferable to continuously feed the raw material MliP so that only one reaction or hydrogen supply becomes rate limiting. After the reaction is completed, the molybdenum-modified Raney nickel is separated from the reaction mixture by a known method and the reaction product is taken out.

〔Example〕

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited in any way by these examples.

Example 1 A molybdenum-modified Raney nickel catalyst (R-230
i Manufactured by Nikko Rica, molybdenum/nickel = 0.4-0.
6% by weight) in wet form (metal equivalent zg) and 150g of MPD, hydrogen gas pressure was 5ky/cd.
(gauge pressure) and purged the system 5 times. After that, the pressure was increased to 9 ky/al (gauge pressure) with hydrogen gas, and Bo
The temperature was raised to 120°C while stirring at 0 rpm. 120℃
When the temperature became constant, 150 g of MHP was continuously supplied over 3 hours. During the reaction, the hydrogen pressure was always maintained at 9 ky/crt (gauge pressure) through a pressure regulating valve, and the off-gas flow rate was adjusted to 151/hr. After the supply of raw materials was completed, the reaction was continued for 1 hour. Next, stirring was stopped, and the mixture was allowed to stand for 1 hour while being allowed to cool. 149 g of the reaction solution was taken out from the sampling port, and after filtering off a trace amount of floating catalyst, it was analyzed by gas chromatography. As a result M
, the conversion rate of EIF was 99.6 mol%, and the MPD
The selectivity to MHP was 96 mol% based on the reacted MHP. The selectivities of β-methyl-δ-valerolactone (MVL) and acetalized by-products were 3 mol % and 1 mol %, respectively, based on the reacted MMP.

Next, the pressure of the autoclave was increased to 9kv'al (gauge pressure), and the temperature was raised to 120°C while stirring at 800 rpm, and when the temperature remained constant at 120°C, the MIIP150
A second reaction was carried out by continuously supplying 1.5 g of 100 g over 3 hours. After the supply of MIiP was completed, the reaction was continued for 1 hour. Next, stirring was stopped and the mixture was allowed to stand for 1 hour while cooling, and then 150 g of the reaction liquid was taken out from the sampling port. Such repeated reactions were performed a total of four times. Conversion rate of MHP, MP
Table 1 shows the selectivity to D, β-methyl-δ-valerolactone and acetalized product.

Table 1 (mol%) MPD MVL Acetal 1 99.6 96 3
12 99.6 95 3
23 98.9 95
3 24 99.2 9
5 3 2 Example 2 In Example 1, except for carrying out using 2 g of molybdenum-modified Raney nickel catalyst (manufactured by Yoken Fine Chemical Co., Ltd., developed with Raney nickel alloy (molybdenum triplex fjkg6)) in a wet state (approximately 1 g in terms of metal). The same operation as in Example 1 was performed three times. Repeat 3rd MH
The conversion rate of P was 98.3 mol%, and the selectivity to MPD was 94 mol% based on the reacted MfiF. MVL
and the selectivity to the acetalate were 3 mol % and 3 mol %, respectively, based on the reacted MfiF.

Example 3 In Example 1, molybdenum-modified Raney nickel catalyst CB-230i manufactured by Nikko Rica, molybdenum/nickel =
0.4 to 0.6 weight ffi%) was used in a wet state of 6 g (approximately 3 y in terms of metal), and the reaction pressure was 3 kg/c11 (gauge pressure).
The same operation as in Example 1 was performed three times, except that The conversion rate of MHP in the third repetition was 98.5 mol %, and the selectivity to h&PD was 92 mol % based on the reacted MIliF. The selectivities to MVL and acetalate were 5 mol % and 3 mol %, respectively, based on the reacted ΔiMP.

Comparative Examples 1 to 3 The same operations as in Example 1 were carried out three times, except that the catalyst and temperature shown in Table 2 were used instead of the molybdenum-modified Raney nickel catalyst. Table 2 shows the M 14 F conversion, MPD, MVL, and selectivity to acetalate for the third repetition.

3 Raneko” 120 79
65 4 31 Ruto

Claims (1)

[Claims] 1,2-hydroxy-4-methyltetrahydropyran is hydrogenated in the presence of a hydrogenation catalyst to produce 3-methylpentane-
A method for producing 3-methylpentane-1,5-diol, which comprises using a molybdenum-modified Raney nickel catalyst as a catalyst in producing 1,5-diol. 2. The manufacturing method according to claim 1, wherein the molybdenum-modified Raney nickel catalyst is a catalyst modified with 0.1 to 10% by weight of molybdenum based on nickel. 3. The production method according to claim 1 or 2, wherein the amount of the molybdenum-modified Raney nickel catalyst used is 0.1 to 10% by weight in terms of metal weight based on the reaction mixture. 4. The production method according to claim 1 or 2, wherein the amount of the molybdenum-modified Raney nickel catalyst used is 0.5 to 5% by weight in terms of metal weight based on the reaction mixture. 5. The manufacturing method according to any one of claims 1 to 4, wherein the pressure of the hydrogenation reaction is 1 to 100 atm. 6. The manufacturing method according to any one of claims 1 to 4, wherein the pressure of the hydrogenation reaction is 2 to 20 atm. 7. The production method according to any one of claims 1 to 4, wherein the hydrogenation reaction pressure is 5 to 15 atm. 8. The manufacturing method according to any one of claims 1 to 7, wherein the hydrogenation reaction temperature is 50 to 180°C. 9. The manufacturing method according to any one of claims 1 to 7, wherein the hydrogenation reaction temperature is 80 to 140°C. 10. The manufacturing method according to any one of claims 1 to 9, wherein the solvent for the hydrogenation reaction is a reaction product.