JPH06104638B2 - Method for producing alcohol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing alcohol. More particularly, the present invention relates to a method for producing alcohol by catalytic hydrogenation of aldehyde.

[Conventional technology]

Conventionally, methods for reducing a carbonyl group of a compound having an aldehyde structure to a hydroxyl group are roughly classified into two categories depending on the form of the catalyst used during the reaction. In the first type, the catalyst is insoluble in the reaction solvent and is called a heterogeneous hydrogenation process. On the other hand, the second type is called a homogeneous hydrogenation method, in which the catalyst is completely soluble in the reaction solvent. The homogeneous hydrogenation method is an industrially desirable method because generally milder reaction conditions than those required for the heterogeneous hydrogenation method can be used.

As a conventional method of uniform hydrogenation using an aldehyde as a raw material, for example, JP-B-60-10013 and JP-A-60-120.
836, JP-A-60-120837 and the like describe a method for producing ethylene glycol by catalytically hydrogenating glycolaldehyde in a liquid phase using a ruthenium compound having an organic ligand as a catalyst. Also, RA Sanchez-delgado and OL de Ochiyoa (de
Ochoa), Journal of Molecular Catalysis, Vol. 6, 303 (1979), and K. Hotta, Journal of Molecula.
ar Catalysis, Vol. 29, p. 105 (1985), describes a method of producing a corresponding alcohol by hydrogenating various aldehyde compounds using a halogen-containing triphenylphosphine-coordinated ruthenium compound as a catalyst. There is. RA Gray (Grey), GP Pez (Pez), A. Waro (W
allo) and J. Corsi, Anals New York Academy of Sciences
K Academy of Sciences) 415, 235 (1983) describes a method of hydrogenating propanal to propanol using a ruthenium hydride compound having an anion charge as a catalyst. However, in the method of catalytic hydrogenation of aldehydes exemplified above, the selectivity is still insufficient, or using a corrosive halogen,
Alternatively, it is difficult to synthesize the catalyst used, and the stability is poor.
It has problems such as difficulty in adopting it as an industrial scale method.

Also, as a document describing a method of hydrogenating a ketone in a liquid phase into an alcohol by using rhodium as a catalyst and phosphine as a co-catalyst, RR Schroc (Schroc
k) and JA Osborn, JCS Chemical
There is page 567 (1970) of Communication (Chemical Communication). The morphology of the catalyst here is the rhodium cation complex [Rh (diene) (P
R ₃ ) ₂ ] ⁺ PF ₆ ⁻ or [Rh (diene) (PR ₃ ) ₂ ] ⁺ ClO ₄ ⁻ , which is effective for reducing ketones, but decarbonylation reaction is effective for reducing aldehydes. It is not suitable as it will occur In order to avoid this drawback, a rhodium cation complex [Rh (i-Pr) ₂ P (C
_{H 2) 3 P (i-} Pr) 2) (NBD) ] ⁺ ClO ₄ ^- (i-Pr is i-
It is a propyl group, and NBD represents norbornadiene. )
Hydrogenation of C ₆ H ₅ CHO and C ₃ H ₇ CHO to give the corresponding alcohols has been reported by Tani et al., Chemistry Letters, page 261 (1982). However, chelating phosphines used are special, it takes a number of steps in the synthesis, ClO _4, further comprising explosive as the counter anion of the cation complex ^- adopted as a method of implementing an industrial scale, such as with There were problems such as difficulty.

On the other hand, when hydroformylation of olephine is carried out using a cobalt carbonyl complex coordinated with phosphine as an example of a catalyst for hydrogenating an aldehyde in the presence of carbon monoxide, the resulting aldehyde undergoes further hydrogenation to give alcohol. Giving is reported in LH Slaugh and RD Marinaux (Mullineaux), Journal of Organometallic Chemistry, Vol. 13, p. 469 (1968).

Also, hydrogenating the aldehyde group of cinnamic aldehyde in the presence of carbon monoxide using RhCl ₃ .3H ₂ O and a specific amount of triethylamine for the rhodium atom as a catalyst to obtain cinnamic alcohol and hydrocinnamic alcohol. Gamo Roki et al., Bulletin of the Chemical Soc
Society of Japan) 50, 2148 (1977).

[Problems to be solved by the invention]

However, any of these methods still has a problem that the catalytic activity and the selectivity of alcohol are still insufficient and it is difficult to adopt as a method for carrying out on an industrial scale.

[Means for solving problems]

The present inventors have arrived at the present invention as a result of earnestly investigating the above facts and using a rhodium catalyst to improve the activity and selectivity of the catalyst.

That is, the present invention relates to a method for producing an alcohol by reacting an aldehyde and hydrogen in a liquid phase in the presence of a rhodium catalyst and carbon monoxide, wherein the reaction system is represented by the general formula PR ₁ R ₂ R ₃ (wherein R ₁ , R ₂ and R ₃ each represent a primary alkyl group, and may be different from each other.) A method for producing an alcohol characterized by the presence of a trialkylphosphine Is.

The present invention will be described in more detail below.

The aldehyde of interest in the present invention has the general formula (I) (In the formula, R ⁴ represents hydrogen or an alkyl group which may have a substituent, a cycloalkyl group, an aryl group or an aralkyl group.).

Examples of the alkyl group include a linear or branched saturated alkyl group having 1 to 50 carbon atoms, preferably 1 to 20 carbon atoms, and these include a hydroxy group, a halogen atom, a carbamoyl group, an amino group and an alkoxy group. It may be substituted with a cyano group, an alkoxycarbonylamino group, a nitro group or the like.

The cycloalkyl group usually includes a cycloalkyl group having a 3 to 20-membered ring. If the cycloalkyl group as a whole has about 3 to 50 carbon atoms, a hydroxy group, a halogen atom, a carbamoyl group can be mentioned. , Amino group, alkoxy group, cyano group, alkoxycarbonylamino group,
It may be substituted with a nitro group or the like.

Examples of the aryl group include aryl groups such as a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group. These are hydroxy groups, halogen atoms, carbamoyl as long as the aryl group as a whole has about 50 or less carbon atoms. It may be substituted with a group, amino group, alkoxy group, cyano group, alkoxycarbonylamino group, nitro group or the like.

Examples of the aralkyl group include an alkyl group having 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, in which one or more hydrogen atoms are substituted with the above aryl group.

Specifically, formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, i-butyraldehyde, n-valeraldehyde, i-valeraldehyde, pivalaldehyde, 2-methylbutyraldehyde, n-capronaldehyde, 2-ethyl. Butyraldehyde, n-heptyl aldehyde, n-capryl aldehyde, 2-ethylhexyl aldehyde, pelargon aldehyde, n-caprin aldehyde, tridecanal, glyoxal, glycol aldehyde, 2-chloropropionaldehyde, 2-aminopropionaldehyde, 4-
Aliphatic aldehydes such as methoxybutyraldehyde, 4-cyanobutyraldehyde, 3-nitropivalaldehyde; cyclopropylaldehyde, cyclobutyraldehyde, cyclopentylaldehyde, cyclohexylaldehyde, cycloheptylaldehyde, 2-methylcyclopropylaldehyde, 2-chloro Cyclopropylaldehyde, 3-aminocyclohexylaldehyde, 4-methoxycyclohexylaldehyde, 4-nitrocyclohexylaldehyde, 3-formyl-1-cyclohexanecarboxylic acid, 4-dimethylcarbamoyloxy-1-cyclohexanecarbaldehyde, 1,4-diformyl Alicyclic aldehydes such as cyclohexane; benzaldehyde, 1-formylnaphthalene, 2-formylnaphthalene, 3-formylnaphthalene, 9- Le mill anthracene, 2-formyl-anthracene, 9-formyl Hue phenanthrene, 2-
Hydroxybenzaldehyde, 4-amino-benzaldehyde, 4-chlorobenzaldehyde, 3-methoxybenzaldehyde, 4-formylbenzoic acid, 9-chloro-
Examples thereof include aromatic aldehydes such as 10-formylanthracene and 1,4-diformylbenzene. Further, the above-mentioned aldehyde may be supplied in the form of a precursor capable of producing the aldehyde of the formula (I) in the reaction system, and for example, aldehyde polymers such as paraformaldehyde, paraaldehyde, etc. may be used. it can.

In the present invention, rhodium is present as a catalyst component.

The rhodium component is a rhodium compound which is neutral or anionic in the reaction zone together with carbon monoxide and trialkylphosphine, which will be described later, such as the general formula [Rhx (CO) y (PR ₁ R ₂
R ₃ ) z ▲] ^n- _m ▼ (where x, y, z, m and n are respectively x ≧ 1,
represents an integer of y ≧ 0, z ≧ 1, m ≧ 1, n ≧ 0, and PR ₁ R
₂ R ₃ represents the above trialkylphosphine. ) Or the general formula _{[HwRhx (CO) y (PR 1} R 2 R 3) z ] n ^- (wherein, w,
x, y, z and n are w ≧ 1, x ≧ 1, y ≧ 0 and z ≧, respectively.
1 represents an integer of n ≧ 0, and PR ₁ R ₂ R ₃ has the same meaning as above. ) And the like are considered to form a rhodium complex. Of these, the rhodium-carbonyl complex in which carbon monoxide is coordinated is considered to be more preferable.

Therefore, either rhodium metal or rhodium compound capable of forming a rhodium carbonyl compound in the reaction zone can be used as the supply form of the rhodium component. Specific examples of the rhodium compound include zero-valent compounds such as dirhodium octacarbonyl; monovalent complex compounds such as acetylacetonatobis (carbonyl) rhodium and promotris (pyridine) rhodium; rhodium trichloride, rhodium nitrate;
Salts such as rhodium acetate; oxides such as rhodium trihydroxide;
Trivalent complex compounds such as tris (acetylacetonato) rhodium; clusters such as tetrarhodium dodecacarbonyl and hexarhodium hexadecacarbonyl; anion complexes such as rhodium tetracarbonyl anion and carbid hexalodium pentadecacarbonyl dianion. .

The amount of rhodium used is the reaction solution 1
Usually 0.0001-100 as rhodium atom per liter
The molar amount is preferably 0.001 to 10 mol.

In the present invention, a specific phosphine is further present as a reaction accelerator. By making a specific phosphine coexist, the activity of the catalyst is significantly improved and the selectivity of alcohol can be increased.

The phosphine is a trialkylphosphine represented by the general formula PR ₁ R ₂ R ₃ (wherein R ₁ , R ₂ and R ₃ represent a primary alkyl group and may be different from each other). Is used. As the primary alkyl groups R ₁ , R ₂ and R ₃ , those having a carbon number of usually 1 to 20, preferably 1 to 10 are used.

Specific examples of the trialkylphosphine used in the present invention include trimethylphosphine, triethylphosphine, tri-n-propylphosphine, tri-n-butylphosphine, tri-n-pentylphosphine, tri- n
-Hexylphosphine, tri-n-heptylphosphine, tri-n-octylphosphine, tri-n-dodecylphosphine, tri-i-butylphosphine, tri-i
-Pentylphosphine, tris (2-ethylhexyl)
Trialkylphosphines having the same primary alkyl group such as phosphines; and diethyl-n-propylphosphine, di-n-butyl-n-propylphosphine, di-
n-butyl-n-octylphosphine, ethyl-n-propyl-n-butylphosphine, di-n-butyl-i-
Trialkyl phosphines having different primary alkyl groups such as butyl phosphine are mentioned.

Among these, it is more preferable that R ₁ , R ₂ and R ₃ are linear primary alkyl groups.

As described above, the above-mentioned trialkylphosphine is considered to coordinate with rhodium in the reaction zone to form a neutral or anionic rhodium carbonyl complex. Therefore, in the present invention, a rhodium complex in which the above trialkylphosphine is pre-coordinated can be used.
Specific examples, RhH (PEt _{3) 4,} [RhH [P (n-
Pr _{3] 4,} RhH [P _{(n-Bu) 3] 4,} Rh _{2 (CO) 2} [P
(N-Bu) ₃ ] ₆ , Rh ₂ (CO) ₂ [P (n-Hex) ₃ ] ₆
Etc. (In the above formulas, Et represents an ethyl group, n-Pr represents an n-propyl group, n-Bu represents an n-butyl group, and n-Hex represents an n-hexyl group).

The amount of the above-mentioned trialkylphosphine used is usually 0.5 to 1000 mol, preferably 1 mol to 1 mol of the rhodium atom.
The amount is in the range of 1.0 to 100 mol, more preferably 3 to 50 mol.

In the present invention, carbon monoxide is present in the reaction system.

As described above, the rhodium component is considered to form a rhodium carbonyl complex with the trialkylphosphine and carbon monoxide in the reaction system. Therefore, in the present invention, free carbon monoxide may be present, or it may be supplied to the reaction system in the form of the rhodium carbonyl complex in which carbon monoxide is previously coordinated with rhodium. . Of these, the presence of free carbon monoxide is more preferred. Further, even when carbon monoxide is supplied to the reaction system in the form of a rhodium carbonyl complex, it is more preferable that free carbon monoxide is further present in the reaction system.

The source of carbon monoxide (free carbon monoxide) and hydrogen used in the present invention is not particularly limited, and may contain a small amount of an inert gas such as nitrogen gas or carbon dioxide. Good. The volume ratio of hydrogen to carbon monoxide is usually in the range of pure hydrogen (when carbon monoxide is present as a rhodium carbonyl complex) to 1/10, and should be used in the composition of 5/1 to 1/5. Is preferred.

The present invention can be carried out in the absence of a solvent, that is, using the reaction raw material and the catalyst component itself as a reaction medium, but a solvent can also be used.

Examples of such a solvent include ethers such as diethyl ether, anisole, tetrahydrofuran, ethylene glycol dimethyl ether and dioxane; alcohols such as methanol, ethanol, n-butanol, benzyl alcohol, phenol, ethylene glycol and diethylene glycol; formic acid and acetic acid. , Propionic acid,
Carboxylic acids such as toluic acid; Esters such as methyl acetate, n-butyl acetate and benzyl benzoate; Aromatic hydrocarbons such as benzene, toluene, ethylbenzene and tetralin; Aliphatic compounds such as n-hexane, n-octane and cyclohexane Hydrocarbons; halogenated hydrocarbons such as dichloromethane, trichloroethane, chlorobenzene; nitromethane,
Nitro compounds such as nitrobenzene; triethylamine,
Tertiary amines such as tri-n-butylamine, benzyldimethylamine, pyridine, α-picoline and 2-hydroxypyridine; carboxylic acid amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone ; Hexamethylphosphoric triamide, N, N, N ', N'
-Inorganic acid amides such as tetraethylsulfamide; N, N '
-Ureas such as dimethylimidazolidone, N, N, N ', N'-tetramethylurea; sulfones such as dimethyl sulfone and tetramethylene sulfone; sulfoxides such as dimethyl sulfoxide and diphenyl sulfoxide; γ-butyrolactone, ε -Lactones such as caprolactone; polyethers such as tetraglyme and 18-crown-6; nitriles such as acetonitrile and benzonitrile; carbonic acid esters such as dimethyl carbonate and ethylene carbonate.

Among the above solvents, it is preferable to use aromatic hydrocarbons, ethers and polyethers.

The reaction of the present invention can be carried out in either a homogeneous system or a heterogeneous suspension system.

The reaction temperature is usually 20 to 300 ° C, but a more preferable temperature range is about 50 to 150 ° C.

The reaction pressure is usually 1 to 600 kg / cm ^2, but preferably 5 to 300 kg / cm ^{2 and more} preferably 30 to 150 kg.
It is carried out at / cm ² .

This method can be carried out in any of batch, semi-continuous and continuous reaction modes.

The alcohol and the like produced by the reaction can be separated by a usual separation method, for example, distillation. Further, the distillation residue can be recycled and reused as a catalyst liquid.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples without departing from the gist thereof.

Example 1 A Hastelloy C autoclave having an internal volume of 35 cc and equipped with a spinner rotary stirrer contains Rh containing 0.05 mmol of rhodium.
(CO) ₂ (acac), tetraglyme 10 ml and tri-n-
Butylphosphine 0.5 mmol was introduced under argon atmosphere. The autoclave was closed and argon was removed by flushing the autoclave three times with a 1: 1 mixture of carbon monoxide and hydrogen of 15 kg / cm ² . About to autoclave
A 1: 1 mixture of carbon monoxide and hydrogen was introduced up to 120 kg / cm ² . Heat the autoclave to 150 ° C and increase the pressure to 150 kg / cm ^2.
As, the autoclave was cooled to room temperature after 1 hour and gas was released.

The resulting pale yellow liquid was used as HCHO under an argon atmosphere to give 10
After adding mmol paraformaldehyde and closing the autoclave, argon was removed by flushing the autoclave 3 times with a 1: 1 mixture of 15 kg / cm ² carbon monoxide and hydrogen. About 450 kg / cm ² of a 1: 1 mixture of carbon monoxide and hydrogen was introduced into the autoclave. Heat the autoclave to 80 ° C and adjust the pressure to 100kg / cm ²
I made a time reaction. Cool the autoclave to room temperature,
Gas was released.

As a result of analyzing the obtained liquid phase by gas chromatography, 0 mmol of formaldehyde (conversion rate 100%) and
The presence of 7.39 mmol of methanol (yield 73.9%, selectivity 73.9%) was confirmed.

Example-2 As a result of carrying out the reaction in the same manner as in Example 1 except that the amount of tri-n-butylphosphine used was 0.2 mmol, the result was 0.0 m.
The presence of mol formaldehyde (100% conversion) and 6.98 mmol methanol (69.8% yield, 69.8% selectivity) was confirmed.

Example 3 Acetylacetonatobis (carbonyl) rhodium Rh (CO) ₂ (acac) containing 0.05 mg of rhodium in an Hastelloy C autoclave having an internal volume of 35 cc, 0.5 mmol of tri-n-butylphosphine, 10.0 mmol of acetaldehyde. , And 10 g of tetraglyme as a solvent were charged, and then an equal volume mixed gas of carbon monoxide and hydrogen was injected up to 90 kg / cm ² at room temperature. Heat the autoclave temperature to 120 ° C and increase the pressure to 100
The reaction was carried out for 2 hours as it was at kg / cm ² . After the reaction, the autoclave was cooled to room temperature, the contents were taken out and analyzed by gas chromatography.
The presence of acetaldehyde (conversion rate 84.2%) and 6.27 mmol ethanol (yield 62.7%, selectivity 74.5%) was confirmed.

Examples-4 to 6 Table-1 shows the results of the reaction performed in the same manner as in Example-3 except that the aldehydes shown in Table-1 were used instead of acetaldehyde.

Example 7 An Hastelloy C autoclave with an internal volume of 35 cc equipped with a spinner rotary stirrer was used to contain Rh (C
O) ₂ (acac), 10 g tetraglyme and 0.3 mmol tri-n-butylphosphine were introduced under an argon atmosphere. The autoclave was closed and the argon was removed by flushing the autoclave three times with a 1: 1 mixture of carbon monoxide and hydrogen at 15 kg / cm ² . About to autoclave
120 kg / cm ² of a 1: 1 mixture of carbon monoxide and hydrogen was introduced. Heat the autoclave to 150 ° C and increase the pressure to 150 kg / cm ^2.
As, the autoclave was cooled to room temperature after 1 hour and gas was released.

0.6 mmol of glycolaldehyde was added to the obtained pale yellow liquid under an argon atmosphere, and the autoclave was closed.
Argon was removed by flushing the autoclave three times with a 1: 1 mixture of 15 kg / cm ² carbon monoxide and hydrogen. About 450 kg / cm ² of a 1: 1 mixture of carbon monoxide and hydrogen was introduced into the autoclave. The autoclave was heated to 150 ° C., the pressure was 500 kg / cm ² , and the reaction was performed for 2 hours as it was. Then, the autoclave was cooled to room temperature and gas was released. As a result of analyzing the obtained liquid phase by gas chromatography, 0 mmol of glycol aldehyde (conversion rate 100%) and 0.58 mmol of ethylene glycol (yield 96.
The presence of 7% and selectivity of 96.7%) was confirmed.

Comparative Example-1 The reaction was carried out in exactly the same manner as in Example-7 except that tri-n-butylphosphine was not used. As a result of analyzing the obtained liquid phase by gas chromatography, it was found to be 0.
11 mmol glycol aldehyde (81.7% conversion) and 0.
06 mmol ethylene glycol (10% yield, 12% selectivity)
Was confirmed.

Examples-8 to 9 The reaction was carried out in the same manner as in Example-7 except that the amount of glycolaldehyde used was changed as shown in Table-2.
The results are shown in Table-2.

Examples-10 to 15 Rh (CO) ₂ (acac) and tri-n-butyphosphine were changed to the amounts shown in Table 3, the amount of glycolaldehyde was changed to 10 mmol, and the reaction pressure was changed to 100 kg / cm ² . The reaction was carried out in the same manner as in Example-7 except that the reaction temperature was 80 ° C and the reaction time was 1 hour. The results are shown in Table-3.

Comparative Examples-2 to 4 Instead of 0.5 mmol of tri-n-butylphosphine, Table-
Table 4 shows the results of the reaction carried out in the same manner as in Example-11 except that the phosphine shown in Table 4 was used in the amount shown in Table-4.
4 shows.

Example 16 An autoclave made of Hastelloy C having an internal volume of 35 cc was added with 0.05 mm.
Rh (CO) ₂ (acac) containing rhodium of ol, tri-n-butylphosphine 0.5 mmol, glycol aldehyde 10.0 mmo
l, and after charging 10 g of tetraglyme as a solvent,
An equal volume mixed gas of carbon monoxide and hydrogen was injected at room temperature to 90 kg / cm ² . The pressure when the temperature of the autoclave was raised to 80 ° C. was 100 kg / cm ² , and the reaction was allowed to proceed for 1 hour. After the reaction, the autoclave was cooled to room temperature, and the contents were taken out and analyzed by gas chromatography. As a result, 0.33 mmol of glycol aldehyde (conversion rate 96.7
%) And 9.23 mmol ethylene glycol (yield 92.7%,
The existence of selectivity (95.4%) was confirmed.

Examples-17 to 24 The reaction was carried out in the same manner as in Example-16 except that the amount of tri-n-butylphosphine used in Table-5 was changed to the solvent shown in Table-5 instead of tetraglyme. . The results are shown in Table-5.
Shown in.

Examples-25 to 28 Carried out except that the amount of rhodium used was 0.01 mmol, 0.1 mmol of trialkylphosphine shown in Table 6 was used in place of tri-n-butylphosphine, and the reaction time was 2 hours. The reaction was carried out as in Example-16. The results are shown in Table-6.

Examples -29 to 31 Example-14 except that the reaction pressure was changed as shown in Table-7.
The results of the reaction performed in the same manner as in Table 7 are shown in Table 7.

Examples 32 to 34 Reactions were performed in the same manner as in Example 16 except that the reaction pressure and the volume ratio of hydrogen to carbon monoxide were changed as shown in Table 8. The results are shown in Table-8.

Example-35 The reaction was performed in the same manner as in Example-14 except that the reaction temperature was changed from 80 ° C to 120 ° C. As a result, 0.29 mmol of glycol aldehyde (conversion rate 97.1%) and 8.67 mmol of ethylene glycol (yield: The existence of 86.7% and 89.3% selectivity was confirmed.

Example-36 The reaction was performed in the same manner as in Example-16 except that the reaction temperature was changed to 120 ° C and the reaction time was changed to 30 minutes. As a result, 0.0 mmol of glycol aldehyde (conversion rate 100%) and 8.83 mmol The presence of ethylene glycol (yield 88.3%, selectivity 88.3%) was confirmed.

Example-37 The reaction was performed in the same manner as in Example-5 except that 0.5 mmol of tri-n-propylphosphine was used instead of tri-n-butylphosphine, and as a result, 7.51 mmol of cyclohexylaldehyde (conversion 24.9%) and 2.04 mmol (Yield 20.4%, selectivity 81.9%) was confirmed.

Comparative Example-5 The reaction was carried out in the same manner as in Example-5 except that 0.5 mmol of tri-i-propylphosphine was used instead of tri-n-butylphosphine, and as a result, 10.0 mmol of cyclohexylaldehyde (conversion 0.0%), Is the trace amount.

〔The invention's effect〕

According to the method of the present invention, alcohols, which are industrially very important chemicals, can be obtained in high yield and high selectivity.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication C07C 33/22

Claims (2)

[Claims] 1. A method for producing an alcohol by reacting aldehyde and hydrogen in a liquid phase in the presence of a rhodium catalyst and carbon monoxide, wherein the reaction system comprises a compound represented by the general formula PR ₁ R ₂ R ₃ (wherein
R ₁ , R ₂ and R ₃ represent a primary alkyl group and may be different from each other. ) The method for producing an alcohol, characterized in that a trialkylphosphine represented by 2. The method for producing alcohol according to claim 1, wherein the carbon monoxide is free carbon monoxide.