JP4306151B2 - Method for producing carbonyl compound - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a carbonyl compound by dehydrogenating alcohol. In particular, the present invention relates to a catalyst used in this reaction.
[0002]
[Prior art]
Several methods for producing a carbonyl compound by dehydrogenating an alcohol in the presence of a complex catalyst have been proposed. For example, J. et al. Orgmet. Chem. 1992, 429, 269-274 describe a reaction in which a lactone is obtained by dehydrogenating a diol using a ruthenium-tetrahydrido-tristriphenylphosphine complex as a catalyst. Bull. Chem. Soc. Jpn. , 1988, 61, 2291-2294 report a dehydrogenation reaction of methanol using a ruthenium-chloro-tetraacetoxy-ethyldiphenylphosphine complex. Bull. Chem. Soc. Jpn. 1988, 61, 2291-2294 report methanol dehydrogenation reaction using an acetic acid-phosphine-ruthenium catalyst. Org. Chem. , 1987, 52, 4319-4327 report a reaction in which an ester is synthesized by dehydrogenating alcohol using a trifluoroacetic acid-triphenylphosphine-ruthenium catalyst.
[0003]
However, the catalysts used in these reported examples are not sufficiently active, and an excess amount of a hydrogen acceptor such as acetone is required to increase the activity. Further, when the catalyst contains chlorine or organic acid, there are problems of side reaction and corrosion due to these, making industrialization difficult. Even a catalyst containing no chlorine or organic acid requires a hydrogenation reagent that is not easy to handle, such as sodium borohydride, which is difficult to implement industrially. In addition, for example, J.A. Org. Chem. , 1987, 52, 4319-4327, Ru (OCOCF ₃ ) ₂ (CO) (PPh ₃ ) ₂ , whose phosphine content is 2 moles compared to ruthenium, is described in the papers with the same reaction activity and selectivity. As shown by the fact that it is lower than RuH ₂ (PPh ₃ ) ₄ , the conventional catalyst has a tendency to lower the catalytic activity when the ratio of the phosphine to the central metal is small.
[0004]
[Problems to be solved by the invention]
Therefore, the present invention provides a dehydration of alcohol using a transition metal complex catalyst in which the ratio of the ligand containing a phosphorus atom to the central metal atom is small and there is no problem of reduction in selectivity and corrosion due to side reactions with acids. It is an object of the present invention to provide a method for producing a carbonyl compound by using an element.
[0005]
[Means for Solving the Problems]
According to the present invention, a ligand containing a phosphorus atom and a ketone compound or diketone compound containing no halogen atom are bonded to ruthenium, and a ligand containing a phosphorus atom for one ruthenium atom A carbonyl compound can be efficiently produced by dehydrogenating alcohol in the presence of a ruthenium complex catalyst in which two are bonded as phosphorus atoms.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The alcohol used for the dehydrogenation reaction in the present invention may be either a monohydric alcohol or a polyhydric alcohol, and the alcohol may be either a primary alcohol or a secondary alcohol. Usually, a saturated or unsaturated alcohol having 1 to 50 carbon atoms, preferably 1 to 10 carbon atoms is used. These alcohols may have a substituent.
[0007]
Examples of some alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, Hexanol, 2-hexanol, 3-hexanol, 1-heptanol, 2-heptanol, 3-heptanol, 4-heptanol, 1-octanol, 2-octanol, 3-octanol, 4-octanol, 1-nonanol, 2-nonanol, 3-nonanol, 4-nonanol, 5-nonanol, 1-decanol, 2-decanol, 3-decanol, 4-decanol, 5-decanol, allyl alcohol, 1-butenol, 2-butenol, 1-pentenol, 2- Pentenol, 1-hexenol, 2 Hexenol, 3-hexenol, 1-heptenol, 2-heptenol, 3-heptenol, 1-octenol, 2-octenol, 3-octenol, 4-octenol, 1-nonenol, 2-nonenol, 3-nonenol, 4-nonenol, 1-decenol, 2-decenol, 3-decenol, 4-decenol, 5-decenol, cyclohexanol, cyclopentanol, cycloheptanol, adamantyl alcohol, 1-phenethyl alcohol, 2-phenethyl alcohol, methanolamine, ethanolamine, etc. Is mentioned. Polyhydric alcohols include those in which two hydroxyl groups are present through 3-6 carbon atoms, such as 1,3-propanediol, 1,4-butanediol, 1,5-hexanediol, 1 , 6-hexanediol, 1,2-cyclohexanedimethylol, 1,3-cyclohexanedimethylol, 1-hydroxymethyl-2-hydroxyethylcyclohexane, 1-hydroxy-2-hydroxypropylcyclohexane, 1-hydroxy-2-hydroxy Ethylcyclohexane, 1-hydroxymethyl-2-hydroxyethylbenzene, 1-hydroxy-2-hydroxypropylbenzene, 1-hydroxy-2-hydroxyethylbenzene and the like are preferable. As alcohol used for the dehydrogenation reaction, 1,4-butanediol is particularly preferred, and γ-butyrolactone is produced in good yield when used as a raw material.
[0008]
The ligand containing a phosphorus atom constituting the ruthenium complex catalyst used in the present invention is usually triphenylphosphine, diphenylmethylphosphine, dimethylphenylphosphine, tridecylphosphine, trinonylphosphine, trioctylphosphine, triheptylphosphine. , Trihexylphosphine, tripentylphosphine, tributylphosphine, tripropylphosphine, triethylphosphine, trimethylphosphine, dimethyloctylphosphine, dioctylmethylphosphine, dimethylheptylphosphine, diheptylmethylphosphine, dimethylhexylphosphine, dihexylmethylphosphine, dimethylpentylphosphine , Dipentylmethylphosphine, dimethylbutylphosphine, dibutylmethylphosphine Tricyclohexylphosphine, tribenzylphosphine, dimethylcyclohexyl phosphine, an organic phosphine such as dicyclohexyl methyl phosphine used. 1,2-bis (dimethylphosphino) ethane, 1,3-bis (dimethylphosphino) propane, 1,4-bis (dimethylphosphino) butane, 1,2-bis (dioctylphosphino) ethane, , 3-bis (dioctylphosphino) propane, 1,4-bis (dioctylphosphino) butane, 1,2-bis (dihexylphosphino) ethane, 1,3-bis (dihexylphosphino) propane, 1,4 -Multidentate coordination of bis (dihexylphosphino) butane, 1,2-bis (dibutylphosphino) ethane, 1,3-bis (dibutylphosphino) propane, 1,4-bis (dibutylphosphino) butane An organic phosphine which is a child can also be used. These organic phosphines may have a substituent. Trialkylphosphine is preferably used. The three alkyl groups of the trialkylphosphine may be linear, branched or a mixture thereof, but is preferably a primary alkyl group.
[0009]
Examples of the ketone compound or diketone compound that does not contain a halogen atom, which is another ligand constituting the ruthenium complex catalyst, include acetone, acetophenone, methyl ethyl ketone, propiophenone, diphenyl ketone, and acetylacetone. Of these, acetylacetone or acetone is preferably used, and acetylacetone is particularly preferred.
[0010]
Some examples of the ruthenium complex catalyst used in the present invention are bis (trimethylphosphino) ruthenium diacetylacetonate, bis (triethylphosphino) ruthenium diacetylacetonate, bis (tripropylphosphino) ruthenium diacetylacetonate, bis ( Tributylphosphino) ruthenium diacetylacetonate, bis (trihexylphosphino) ruthenium diacetylacetonate, bis (trioctylphosphino) ruthenium diacetylacetonate, bis (triphenylphosphino) ruthenium diacetylacetonate, bis (diphenylmethylphosphine) Fino) ruthenium diacetylacetonate, bis (dimethylphenylphosphino) ruthenium diacetylacetonate, and the like. From the viewpoint of the stability of the organic phosphine, the alkylphosphine complexes bis (trimethylphosphino) ruthenium diacetylacetonate, bis (triethylphosphino) ruthenium diacetylacetonate, bis (tripropylphosphino) ruthenium diacetylacetonate, It is preferable to use bis (tributylphosphino) ruthenium diacetylacetonate, bis (trihexylphosphino) ruthenium diacetylacetonate, bis (trioctylphosphino) ruthenium diacetylacetonate, etc. Among them, bis (tributylphosphino) ruthenium It is preferable to use diacetylacetonate or bis (trioctylphosphino) ruthenium diacetylacetonate.
[0011]
The ruthenium complex catalyst used in the present invention is a known compound and can be synthesized by a known method. For example, bis (tributylphosphino) ruthenium diacetylacetonate can be synthesized by stirring a ruthenium (acetylacetonate) dimethylbutadiene complex with 2 moles of tributylphosphine in an argon atmosphere. The ruthenium (acetylacetonate) dimethylbutadiene complex, a precursor complex, is synthesized by stirring ruthenium acetylacetonate and an excess amount of dimethylbutadiene, preferably 2 to 20 moles of dimethylbutadiene, in the presence of zinc metal. it can. In addition to dimethylbutadiene, other olefins and dienes can be used, and isoprene, butadiene and the like are particularly preferable.
[0012]
In addition, as for a ruthenium complex catalyst, the precursor can be added to a reaction system, and a catalyst can also be produced | generated within a reaction system besides using what was synthesize | combined beforehand.
The carbonyl compound produced by the present invention is an aldehyde, a ketone, an ester or the like depending on the alcohol to be subjected to the dehydrogenation reaction, such as formaldehyde, acetaldehyde, propanal, butanal, pentanal, hexanal, heptanal, octanal, nonanal, decanal, etc. Aldehydes, ketones such as 2-propanone, 2-butanone, 2-pentanone and 3-pentanone, diketones such as acetylacetone, and esters such as γ-butyrolactone.
[0013]
The production of the carbonyl compound according to the present invention is preferably carried out without the presence of a solvent, that is, using the reaction raw material and the product itself as a solvent, but a solvent can also be used. Examples of the solvent include ethers such as diethyl ether, anisole, tetrahydrofuran, ethylene glycol dimethyl ether and dioxane, esters such as methyl acetate, butyl acetate and benzyl benzoate, aromatic hydrocarbons such as benzene, toluene, ethylbenzene and tetralin, aliphatic hydrocarbons such as n-hexane, n-octane and cyclohexane, nitro compounds such as nitromethane and nitrobenzene, carboxylic acid amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone, hexamethyl Phosphoric triamide and other amides, ureas such as N, N-dimethylimidazolidinone, sulfones such as dimethyl sulfone, sulfoxides such as dimethyl sulfoxide, γ-butyrolactone, caprolacto Lactones etc., tetraglyme, polyethers such as triglyme, dimethyl carbonate, although carbonate esters such as ethylene carbonate and the like, preferably ethers, polyethers, esters and the like.
[0014]
The dehydrogenation reaction is usually performed at 20 to 350 ° C. It is preferable to carry out at 100 to 250 ° C, particularly 150 to 220 ° C.
The reaction can be performed under reduced pressure, normal pressure, or increased pressure, and is usually performed at 0.001 to 10 MPa. The atmosphere is preferably air or an inert gas atmosphere such as nitrogen, argon, helium, carbon dioxide. Since the reaction is promoted by removing hydrogen produced by the reaction, it is also preferable to carry out the reaction in an open system. The reaction can be carried out either batchwise or continuously.
[0015]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, unless it exceeds the summary of this invention, it is not limited to a following example.
Example 1
In a 70 mL glass Schlenk tube, 966 mg of ruthenium acetylacetonatodimethylbutadiene complex in which 2 mol each of acetylacetone and dimethylbutadiene are bonded to ruthenium, and 1.26 mL of tri-n-butylphosphine (2 times mol to ruthenium) , And 15 mL of toluene. The mixture was heated to reflux for 12 hours using an oil bath at 170 ° C. The solvent was distilled off under reduced pressure to obtain orange crystals of bis (tributylphosphino) ruthenium diacetylacetonate. Yield 1.78 g, yield 100%. ¹ H NMR (C ₆ D ₆ ): d 0.96 (t, J = 7.2 Hz), 1.02 (t, J = 7.2 Hz), 1.25 2.06 (m), 5.21 (S), 5.34 (s)
In a 100 mL flask equipped with a stirrer, a condenser, a temperature measuring device, and a sampling port, 7.3 g of 1,4-butanediol was added and heated to 205 ° C. Thereto, 101 mg of bis (tributylphosphino) ruthenium diacetylacetonate synthesized above was diluted with 2 mL of triglyme, and heated and stirred at 203 ° C. for 9 hours (Ru metal concentration 2000 wtppm). As a result of GC analysis of the reaction solution by an internal standard method, the conversion of 1,4-butanediol was 88% and the selectivity for γ-butyrolactone was 87%.
[0016]
Conventionally reported catalysts containing an acid component such as Ru (OCOCF ₃ ) ₂ (PPh ₃ ) ₂ are described in J. Org. Org. Chem. , 1987, 52, 4319-4327, the selectivity is about 30%, and an ether compound is produced by a side reaction, but the production of ether by-product is 1% or less.

Claims (3)

A process for preparing an alcohol dehydrogenating carbonyl compounds in the presence of a ruthenium complex catalyst, had a ruthenium complex catalyst, such contain trialkylphosphine and a halogen atom which three alkyl groups in the phosphorus atom is bonded and di ketone compound binds to the ruthenium, and trialkyl phosphines are three alkyl groups in the phosphorus atom is bonded to one ruthenium atoms are bonded two of phosphorus atoms, and include a halogen atom A method comprising using two diketone compounds bonded together . The method according to claim 1, wherein the ruthenium constituting the ruthenium complex catalyst is divalent ruthenium. The method according to claim 1 or 2, wherein the alcohol is 1,4-butanediol and the carbonyl compound to be formed is γ-butyrolactone.