Entitled: alpha-producing method of fluoroaldehyde

Technical field

[0001]

　The present invention relates to a process for producing α- fluoro aldehydes.

Background technique

[0002]

　As the conventional method of manufacturing a perfluorinated aldehydes, a method of manufacturing by reducing the perfluoro ester with lithium aluminum hydride is known (Non-Patent Document 1).

[0003]

　alpha, as a method for producing α- difluoro acetaldehyde, alpha, the α- difluoro acetic acid esters, there is known a method of manufacturing by reducing the hydride reducing agent such as lithium aluminum hydride (Non-Patent Document 2) .

[0004]

　On the other hand, ruthenium / tin type bimetallic catalyst (valences -4, coordination number by reducing ruthenium complex of 6, preparing a ruthenium / tin type metal catalyst) in the presence of a carboxylic acid in the vapor phase, a carboxylic acid ester or by reducing the carboxylic acid anhydride, a method for producing a corresponding aldehyde and its derivatives have been disclosed (Patent Document 1).

[0005]

　Furthermore, the α- fluoro acetic acid esters in the presence of a ruthenium catalyst (homogeneous catalyst), in the liquid phase, by reacting with hydrogen gas, a method of manufacturing the α- fluoro aldehyde (Patent Document 2), also, alpha, the α- difluoro acetic acid esters in the presence of a ruthenium catalyst (homogeneous catalyst), in the liquid phase, by reacting with hydrogen gas, alpha, a method of manufacturing the α- difluoro acetaldehyde (Patent Document 3) is known It is.

CITATION

Patent Literature

[0006]

Patent Document 1: U.S. Patent No. 5,476,827 Pat
Patent Document 2: WO 2013/018573 Patent Publication
Patent Document 3: WO 2014/115801 Patent Publication

Non-Patent Document

[0007]

Non-Patent Document 1: Journal of American Chemical Society, 1954, 76 (1), p.300-301.
Non-Patent Document 2: Journal of Organic Chemistry, 1993 , 58, p.2302-2312.

Disclosure of the Invention

Problems that the Invention is to Solve

[0008]

　The method described in Non-Patent Document 1 and Non-Patent Document 2, is used a hydride reducing agent, it postprocessing is often cumbersome and wastes, also, there are also secondary production of ethanols by over-reduction, industrial scale in order to manufacture there was a flame. The method described in Patent Document 1 is used bimetallic system ruthenium / tin, and requires heating of 200 ° C. or higher for reaction a is in the vapor phase, it is those energy efficient improvement is desired It was. On the other hand, the method described in Patent Document 2 and Patent Document 3, ethanols that ruthenium catalyst is is economically disadvantageous and expensive, and by sequentially over-reduction to produce the desired product aldehyde and the aldehyde used and but there has been greatly influenced tendency by the conversion rate.

[0009]

　The present invention uses the esters having a fluorine atom, an inexpensive conditions that may industrially employed, and to provide a process for producing aldehydes with good selectivity fluorine atom.

Means for Solving the Problems

[0010]

　The present invention has been made in consideration of the above situation, the present inventors have studied intensively, the α- fluoro esters in the presence of a base and specific catalysts, hydrogen (H 2 is reacted with) by, it obtained a finding that can produce the corresponding α- fluoro aldehydes with high selectivity, thus completing the present invention.

[0011]

　That is, the present invention [Invention 1] - provides described in [Invention 17] The method of α- fluoro aldehydes.

[0012]

　[Invention 1]
　to α- fluoroester represented by the general formula [1], ruthenium compound, a catalyst rhodium compound, or a platinum compound supported on a metal oxide or activated carbon, and the presence of a base, the hydrogen (H 2 ) by reacting a process for producing α- fluoro aldehydes represented by general formula [2].
[Chemical formula 1]

wherein, R 1 represents a hydrogen atom, a halogen atom or a haloalkyl group, R 2 represents an alkyl group or a substituted alkyl group. ]
[Formula 2]

wherein, R 1 has the formula [1] the same as. ]

[0013]

　[Invention 2]
　the base is imine base or an inorganic base A process according to the invention 1.

[0014]

　[Invention 3]
　base is alkoxide of alkali metal A method according to Invention 1 or 2.

[0015]

　[Invention 4]
　The reaction is carried out by adding a base or catalyst sequential method according to any one of Inventions 1 to 3.

[0016]

　[Invention 5]
　The amount of the base is, the general formula [1] shown by α- fluoroester 1 mol per 0.01 mol or more and 3 mol or less, according to any one of Inventions 1 to 4 Method.

[0017]

　[Invention 6]
　successive addition performs the base is divided into at least twice, the method according to the invention 4.

[0018]

　[Invention 7]
　successive addition performs catalyst was divided into at least twice, the method according to the invention 4.

[0019]

　[Invention 8]
　ruthenium compounds, fluorides of ruthenium, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride, the invention 1 to 7 the method according to any one.

[0020]

　[Invention 9]
　rhodium compound is a fluoride of rhodium, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride, the invention 1 to 7 the method according to any one.

[0021]

　[Invention 10]
　platinum compounds, fluorides of platinum, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride, the invention 1 to 7 the method according to any one.

[0022]

　[Invention 11]
　metal oxide is alumina, zirconia, titania, silica or magnesia, A method according to any one of Inventions 1 to 7.

[0023]

　[Invention 12]
　in the range of hydrogen pressure is 0.001 ~ 4 MPa, and is characterized in that in a range of 0 ~ 40 ° C. as a reaction temperature, method according to any one of Inventions 1 to 11.

[0024]

　[Invention 13]
　the reaction is carried out in the presence of an alcohol, The method according to any one of Inventions 1 to 12.

[0025]

　[Invention 14]
　After completion of the reaction, recovering the catalyst used is carried out by recycling method according to any one of Inventions 1 to 13.

[0026]

　[Invention 15]
　catalyst recovery, the catalyst was filtered off, carried out by washing with water and then an alcohol The method according to the invention 14.

[0027]

　[Invention 16]
　water in the reaction system and carrying out a range of 0.001 to 0.5 wt%, The method according to any one of Inventions 1 to 15.

[0028]

　[Invention 17]
　alpha-fluoro aldehyde represented by the general formula [2], comprising obtaining as alpha-fluoro aldehyde equivalents represented by the following formula The method according to any one of Inventions 1 to 16.
[Chemical Formula 3]

[wherein, R 1 is R in the general formula [1] 1 are the same as. R 3 represents an alkyl group or a substituted alkyl group. ]

[0029]

　Using a specific metal catalyst, hydrogenation in ketone bodies or aldehyde no fluorine atom (reduction) reactions have been known for a long time and also the hydrogenation reaction to the ester moiety are also known. On the other hand, the reduction reaction to an ester compound having a fluorine atom, the effect of specific reactivity with the fluorine atom, the other aldehyde of the object, resulting often by-products of the alcohols and the like which are over-reduction at the same time there are many. For example, International Publication No. 2012/105431, the esters having a fluorine atom, the presence certain ruthenium catalysts, an example in which a reduction reaction was performed with hydrogen gas is disclosed, the desired aldehyde product here rather than the body, that the β- fluoroalcohol excessively reduction reaction has proceeded is generated at high conversion and high selectivity it has been disclosed. This specific reactivity possessed by the fluorine atom, the ester (with high selectivity) is presumed that was converted to an alcohol body.

[0030]

　From the above, the reduction reaction to esters having a fluorine atom, although depending on the type of catalyst difference comes into reactive under the conditions of the aldehyde compound as the target compound can be industrially employed in the present invention, and efficiently it was expected to be very difficult to obtain.

[0031]

　However, the present inventors have found that the esters having a fluorine atom, the presence of a base and specific catalysts, to attempt the reduction reaction with hydrogen, the manufacture of the desired product in which aldehyde with at surprisingly high selectivity knowledge was obtained are possible. Furthermore, the type and amount of base and catalyst, such as a method for introducing reactants, by subjecting the specific reaction conditions, obtained a finding to obtain aldehydes with a very high selectivity, further the catalyst recovered after the reaction, the knowledge that can be reused to the invention were also obtained. These findings, in the present invention, compared with conventional methods, and to produce the desired product with high selectivity, became to be able to cost reduction since it is possible to reuse the catalyst. Also not applied load on the productivity, a very excellent method. Incidentally, as in the present invention, alpha-fluoro ester of the presence of a catalyst and a base to be used in the present invention, by reacting with hydrogen, the method of producing the alpha-fluoro aldehyde has not been known.

Effect of the invention

[0032]

　According to the present invention, is used for easy availability of raw materials as compared with the prior art, good conversion rate and selectivity, there is an effect that it is possible to provide a method for producing α- fluoro aldehyde.

DESCRIPTION OF THE INVENTION

[0033]

　The present invention will be described in detail. The scope of the invention should not be restricted to these descriptions, even with the addition to the following examples, can be suitably changed and then practiced within a range not departing from the spirit of the present invention. Note that all of the publications cited herein, for example, prior art documents, and publications, patent publications and other patent documents, are incorporated herein by reference.

[0034]

　Method for producing alpha-fluoro aldehydes according to the present invention (hereinafter sometimes referred to as the production method of the present invention.), As described above, alpha-fluoro ester of the presence of a base and a catalyst, hydrogen (H 2 ) by reaction with a process for producing α- fluoro aldehyde.

[0035]

　R of α- fluoroester represented by the general formula [1] 1 represents a hydrogen atom, a halogen atom or a haloalkyl group. The halogen atom is a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. The haloalkyl group having 1 to 18 carbon atoms, an alkyl group of straight or branched chain or cyclic (in the case of 3 or more carbon atoms), on any of the carbon atoms, any number and in combination, with the halogen atoms. Fluorine atoms among the halogen atom is preferable.

[0036]

　R of α- fluoroester represented by the general formula [1] 2 represents a substituted or unsubstituted alkyl group. Unsubstituted alkyl groups, having 1 to 18 carbon atoms, is of straight or branched or cyclic (in the case of 3 or more carbon atoms). Of these, linear or branched alkyl group, preferably an alkyl group having 1 to 10 carbon atoms, a cyclic alkyl group having 3 to 12 carbon atoms are preferred.

[0037]

　Specific examples of unsubstituted alkyl groups include methyl group, ethyl group, n- propyl group, i- propyl, n- butyl group, i- butyl, s- butyl, t- butyl group, n- pentyl group, a cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, a norbornyl group and an adamantyl group.

[0038]

　Substituted alkyl group, on any carbon atom of the unsubstituted alkyl group, in any number and combination, an alkyl group having a substituent. Substituents according to fluorine, chlorine and halogen atom such as bromine, lower alkyl groups such as methyl group, ethyl group and propyl group, fluoromethyl group, chloromethyl group and a lower haloalkyl group such as a bromomethyl group, a methoxy group, an ethoxy group and lower alkoxy groups such as propoxy, fluoromethoxy group, chloromethoxy group and a lower haloalkoxy group such as bromo methoxy group, a cyano group, a methoxycarbonyl group, a lower alkoxycarbonyl group such as methoxycarbonyl group and ethoxycarbonyl group and a propoxycarbonyl group, a carboxyl group , protected carboxyl group, an amino group, protected amino group, a protected form, such as a hydroxyl group, and a hydroxyl group. Depending on the kind of substituents in some cases a substituent is itself involved in side reactions, but can be minimized by adopting suitable reaction conditions.

[0039]

　In this specification, the term "lower", having 1 to 6 carbon atoms, means a straight-chain or branched chain or cyclic (in the case of 3 or more carbon atoms). Further, the protecting group of carboxyl group, amino group and hydroxyl group, Protective Groups in Organic Synthesis, Third Edition, 1999, John Wiley & Sons, is a by protecting groups described Inc., Etc., specifically, alkyl group is preferably a methyl group.

[0040]

　Among alpha-fluoro ester represented by the general formula [1], alpha is represented by the following formula, alpha-difluoro acetic acid esters are preferred, readily available in large scale.
[Formula 4]

[wherein, R 2 is R in the general formula [1] 2 is the same as. ]

[0041]

　The catalyst used in the production process of the present invention is not particularly limited as long as it has a solid catalysis the catalyst is a ruthenium compound, using a catalyst rhodium compound, or a platinum compound supported on a metal oxide or activated carbon .

[0042]

　Among them, ruthenium compound used in the preparation of the ruthenium compound supported catalyst, fluoride ruthenium, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride is there.

[0043]

　On the other hand, used in the preparation of the rhodium compound supported catalyst or a platinum compound supported catalyst, specific examples of the rhodium compound or a platinum compound, a fluoride of a rhodium compound or a platinum compound, a chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride.

[0044]

　The metal oxide or activated carbon, ruthenium compound, which functions as a "carrier" rhodium compound, or a platinum compound bearing. The type of the metal oxide is at least one of alumina, zirconia, selected from the group consisting of titania, silica, and magnesia.

[0045]

　Meanwhile, the activated carbon may be used to choose from among these because various ones are commercially available. For example, activated carbon produced from bituminous coal (for example, manufactured by Calgon granular activated carbon CAL (Toyo Calgon Corporation), palm husk charcoal (for example, manufactured by Japan EnviroChemicals, Ltd.) and the like can be mentioned, of course, these types It is not limited to.

[0046]

　Methods of preparing the catalyst used in the present invention is not limited, for example, ruthenium compounds, dissolved in a rhodium compound, or a platinum compound solution, the solution was impregnated into the carrier, hydrogen (H while heating 2 reduced at) It can be adjusted by. Or, pre hydrogen fluoride carrier, the compound modification treatment with halogen hydrogen chloride, and the like chlorinated fluorinated hydrocarbon, ruthenium compounds, or impregnated with a solution of soluble compounds of the rhodium compound, or a platinum compound, a spray It can be prepared by.

[0047]

　The soluble compounds referred to herein, water, hydrochloric acid, ammonia water, ethanol, the corresponding metal to be dissolved in a solvent such as acetone nitrate, phosphate, chloride, oxide, oxychloride, oxyfluoride, and the like .

[0048]

　Ruthenium compounds, rhodium compounds or platinum compound, the supported amount to the carrier is a percentage of the total amount of the carrier is 0.1 to 80 wt%, and preferably from 1 to 40% by weight.

[0049]

　Of the catalysts prepared by the above method, the metal oxide for the catalyst as a carrier, previously treated with hydrogen fluoride, fluorinated agents such as fluorinated hydrocarbons under the given reaction temperature or more before use, it is effective to perform the activity of the catalyst. In activation of the catalyst may be used after treatment with previously chlorinated hydrocarbons, a method of fluorination. Further, oxygen in the reaction, chlorine, extension of fluorinated or chlorinated hydrocarbons, such as that fed into the reactor catalyst life, reaction rate, is an effective means for improving the reaction yield.

[0050]

　Further, in the present invention, the use of high water content catalyst, under the influence of bases that are separately into the reaction system exists, hydrolysis the starting material alpha-fluoro ester proceeds preferentially, alpha- may fluorocarboxylic acid is produced. Because the present reaction conditions does not proceed the reduction reaction to α- fluoro carboxylic acids, the use of high water content catalyst unfavorably reduced yield. The water content of the catalyst is good to use the following 50% by weight, preferably not more than 20 wt%, more preferably at most 2 mass%. Also, of course also the water from the solvent and a base, to affect the hydrolysis of the raw material, the smaller is preferred. The catalyst, solvent, bases, moisture in the reaction system obtained by mixing raw materials may be performed in the range of 10 to 0.001 wt%, preferably from 5 to 0.001 mass%, more preferably from 0.5 to 0.001 % by mass.

[0051]

　The amount of the catalyst has the general formula with respect to α- fluoroester represented by [1], may be not less than 0.01 wt%, preferably 1 to 100 mass%, more preferably 5 to 30 wt%.

[0052]

　The base used in the present invention,
(a) 3 amines, (b) nitrogen-containing aromatic heterocyclic compound, (c) an following imine backbone: -C = N-C- compounds having (Note that this specification in writing, the compound may be referred to as "imine base"), an organic base, selected from
(d) an inorganic base,
or
(e) tetraalkyl ammonium hydroxide, an.

[0053]

　Specific examples of each of the compounds, the following demonstrates.

[0054]

　(A) tertiary amines: trimethylamine, triethylamine, N- ethyldiisopropylamine, tri -n- propylamine, triisopropylamine, tri -n- butylamine, trioctylamine, tridecylamine, triphenylamine, tribenzylamine, tris (2-ethylhexyl) amine, N, N- dimethyldecylamine, N- benzyldimethylamine, N- butyl-dimethylamine, N, N- dimethylcyclohexylamine, N, N, N ', N'- tetramethyl ethylenediamine, N, N- dimethylaniline, N, N- diethylaniline, 1,4-diazabicyclo [2.2.2] octane, N- methylpyrrolidine, N- methylpiperidine, N- methylmorpholine, N- ethylmorpholine, N, N'-dimethyl piperazine, N- main Rupipekorin, N- methylpyrrolidone, N- vinyl - pyrrolidone, bis (2-dimethylamino - ethyl) ether, N, N, N, N ', N' '- pentamethyl - diethylenetriamine, triethanolamine, tripropanolamine, dimethyl ethanolamine, dimethylaminoethoxyethanol, N, N-dimethylaminopropyl amine, N, N, N ', N', N '' - pentamethyl dipropylenetriamine, tris (3-dimethylaminopropyl) amine, tetramethyl-imino - bis (propylamine), N- diethyl - such as ethanolamine.

[0055]

　(B) nitrogen-containing aromatic heterocyclic compound: pyridine, 2,4,6-trimethylpyridine, 4-dimethylaminopyridine, lutidine, pyrimidine, pyridazine, pyrazine, oxazole, isoxazole, thiazole, isothiazole, imidazole, 1 , 2-dimethylimidazole, 3- (dimethylamino) propyl imidazole, pyrazole, furazan, pyrazine, quinoline, isoquinoline, purine, 1H-indazole, quinazoline, cinnoline, quinoxaline, phthalazine, pteridine, phenanthridine, 2,6-di -t- butyl pyridine, 2,2'-bipyridine, 4,4'-dimethyl-2,2'-bipyridyl, 4,4'-dimethyl-2,2'-bipyridyl, 5,5'-dimethyl-2, 2'-bipyridyl, 6,6'-t- butyl-2,2'-Jipiri Le, 4,4'-diphenyl-2,2'-bipyridyl, 1,10-phenanthroline, 2,7-dimethyl-1,10-phenanthroline, 5,6-dimethyl-1,10-phenanthroline, 4,7 diphenyl-1,10-phenanthroline.

[0056]

　(C) imine bases: 1,8-diazabicyclo [5.4.0] undec-7-ene, 1,5-diazabicyclo [4.3.0] non-5-ene.

[0057]

　(D) an inorganic base alkali metal, hydrides of alkaline earth metal (sodium hydride, potassium hydride, lithium hydride, calcium hydride, etc.), alkali metal, alkaline earth metal hydroxides (sodium hydroxide , potassium hydroxide, lithium hydroxide, calcium hydroxide, etc.), alkali metal, carbonates (sodium carbonate of an alkaline earth metal, potassium carbonate, lithium carbonate, calcium carbonate, etc.), hydrogen carbonates (sodium hydrogen carbonate of an alkali metal , potassium hydrogen carbonate, lithium hydrogen carbonate), an alkali metal, oxide of an alkaline earth metal (lithium oxide, sodium oxide, potassium oxide, calcium oxide, magnesium oxide), alkali metal, alkaline earth metal halides (fluoride lithium hydride, sodium fluoride, potassium fluoride, cesium fluoride, Kka magnesium, calcium fluoride, cesium chloride, etc.), alkali metal alkoxides (lithium methoxide, sodium methoxide, potassium methoxide, lithium ethoxide, sodium ethoxide, potassium ethoxide, lithium isopropoxide, sodium isopropoxyphenyl de, potassium isopropoxide, lithium tert- butoxide, sodium tert- butoxide and potassium tert- butoxide) and the like.

[0058]

　(E) tetraalkyl ammonium hydroxide: tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n- propyl ammonium hydroxide, tetra n- butylammonium.

[0059]

　Among these, imine base as organic base or inorganic base, is preferred. Among the imine base 1,8-diazabicyclo [5.4.0] undec-7-ene is more preferable. On the other hand, more preferably an alkoxide of an alkali metal inorganic bases, among others, sodium ethoxide, potassium ethoxide, is highly preferred lithium ethoxide or potassium tert- butoxide.

[0060]

　The amount of the base to be used, the general formula can be used more than 0.001 mol per α- fluoroester 1 mole represented by [1], preferably 0.005 to 5 mol, 0.01 to 3 moles particularly preferred.

[0061]

　In the present invention, in addition to the abovementioned bases, fluoride ions in order to prevent deactivation of the catalyst (F - ) as a scavenger, Group 13, at least one hydroxide selected from the metals belonging to Group 14 (hydroxide aluminum, gallium hydroxide, indium hydroxide) or oxides (aluminum oxide, gallium oxide, indium oxide, may be added as silicon dioxide, germanium dioxide, tin oxide).

[0062]

　Aluminum hydroxide Among these, gallium hydroxide, indium hydroxide, silicon dioxide is preferable, aluminum hydroxide is particularly preferred. Incidentally, these may be mixed with either alone or in one or more.

[0063]

　The amount of fluoride ion-capturing agent has the general formula may be used more than 0.001 mol per α- fluoroester 1 mole represented by [1], preferably 0.005 to 5 mol, 0.03 to 1 mol it is particularly preferred.

[0064]

　It can be used a reaction solvent in the production method of the present invention. The reaction solvent may be any inert under the conditions of the present reaction is not particularly limited, for example, aliphatic hydrocarbons, aromatic hydrocarbons, nitriles, acid amides, lower ethers, alcohols and the like.

[0065]

　Among them, lower ethers and alcohols are preferred, alcohols are particularly preferred.

[0066]

　Specific compounds, n- pentane, n- hexane, n- heptane, benzene, toluene, xylene, acetonitrile, propionitrile, phenylacetonitrile, isobutyronitrile, benzonitrile, dimethylformamide, dimethylacetamide, methylformamide , formamide, hexamethylphosphoric triamide, N- methylpyrrolidone, diethyl ether, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, 1,2-epoxy, 1,4-dioxane, dibutyl ether, t- butyl methyl ether, substituted tetrahydrofuran, methanol, ethanol, n- propanol, isopropanol, n- butanol, tert- butanol, n- pentanol, n- hexanol and cyclohex Lumpur, and the like. Among them, diethyl ether, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, and 2-epoxy ethane, and methanol, ethanol, n- propanol, isopropanol, n- butanol, tert- butanol, n- pentanol , n- hexanol and cyclohexanol are preferred, methanol, ethanol and n- propanol is highly preferred.

[0067]

　These reaction solvents can be used alone or in combination. In the production of the target product α- fluoro aldehydes, easy methanol separation by fractional distillation, ethanol and n- propanol is highly preferred.

[0068]

　The amount of the reaction solvent, the formula may be used to 0.01 L (liter) or more with respect to α- fluoroester 1 mole represented by [1], preferably 0.03 ~ 10L, 0.05 ~ 7L It is particularly preferred. The reaction can also be carried out in neat state without using a reaction solvent.

[0069]

　Hydrogen (H 2 usage) of the general formula may be used more than 1 mol per α- fluoroester 1 mole represented by [1], and preferably about 1 to 10 moles, more preferably 1 ~ is a 5 moles.

[0070]

　Hydrogen pressure is not particularly limited, usually, 0.001 ~ 10 MPa (absolute pressure reference. Hereinafter, in this specification the same) may be carried out in a pressure range of, preferably 0.001 ~ 5 MPa. To maximize the effects of the present invention are very preferably 0.001 ~ 4 MPa.

[0071]

　The reaction temperature may at -30 ° C. ~ 100 ° C., preferably from 0 ° C. ~ 70 ° C., more preferably from 0 ° C. ~ 40 ° C. are preferred. It is lower than the reaction temperature -30 ° C. The reaction may slow. On the other hand, catalyst life is shortened when the reaction temperature exceeds 100 ° C., while, the reaction proceeds rapidly, the decomposition products and the like are produced, selectivity in the present invention may be lowered.

[0072]

　In the present invention, alpha-fluoro ester time of the reaction of hydrogen with respect to, the hydrogen pressure is in a range of 0.001 ~ 4 MPa, and at a range of 0 ~ 40 ° C. as a reaction temperature, alpha-fluoro aldehyde also because it can produce a kind efficiently, which is one of the preferred embodiments.

[0073]

　The charging method of the reaction system of catalyst and a base in the present invention may be charged at the same time the catalyst and a base in the reaction system, whereas it may be charged a catalyst and a base separately to the reaction system. Further, catalyst and a base may be added simultaneously sequential were charged the required amount to the reaction system either the catalyst or base, it may be added to other reagents sequentially. Here, the "sequential addition" means the addition of catalysts and / or bases, an agent to the reaction system sequentially one after another intermittently to the reaction system (refers to separating a certain time) . As in the present invention, with respect to α- fluoro acetates 1 mol in the reaction system, so that the base is 1 mol to 0.25 mol in molar equivalents, 0.0001 mole catalyst in a molar equivalent to 0.03 so that the molar, the catalyst and / or base, it is also possible to added in portions to at least twice, the additive method is a preferred embodiment of the present invention.

[0074]

　Activation method of the catalyst used in the regeneration of the catalyst, a general method may be employed. For example, dry air, chlorine, can be reactivated by contacting appropriate with decreased activity in the catalyst hydrogen fluoride. As a method for activating a catalyst without contact with these gases, the separated catalyst after used in the reaction, by washing with water and / or alcohol (such as ethanol), can also be used repeatedly, this is one of the preferred embodiments (examples 17 and 18).

[0075]

　Production method of the present invention, for example, nitrogen, can be carried out in an inert gas atmosphere such as argon. Reactor, hydrogen fluoride heat resistance, it is sufficient made of a material having corrosion resistance against hydrogen chloride, stainless steel, Hastelloy TM , Monel TM , and platinum are preferable. It can also be made of a material lined with these metals.

[0076]

　The reaction time is different may be performed within 72 hours, the raw material substrate and the reaction conditions (reaction temperature, kind of catalyst, amount) by. H from the pressure of the reaction vessel 2 consumption condition of observation at any time, hydrogen (H 2 it is preferred that the consumption of) to terminate the reaction at the stage of completion virtually. Alternatively, gas chromatography, liquid chromatography to follow the progress of the reaction by an analytical means nuclear magnetic resonance, etc., the time when the reduction of the raw material substrate was not recognized almost be the end point of the reaction preferred.

[0077]

　Α- fluoroaldehyde of the formula [2] is a powerful since the electron withdrawing group is an aldehyde which is directly connected, self-polymerization of the aldehydes, stable equivalent of such hydrated form or hemiacetal thereof If obtained as many (of course, it can also be obtained in the form of an aldehyde in some cases). For example, in the present invention, referred to herein as "hemiacetal form", compounds represented by the following formula is obtained as α- fluoroaldehyde equivalent.
[Chemical Formula 5]

[wherein, R 1 is R in the general formula [1] 1 are the same as. R 3 represents an alkyl group or a substituted alkyl group. ]

[0078]

　Therefore, the α- fluoro aldehyde represented by the general formula [2] in the claims, handled as contained even these stable equivalents. Alcohols, alcohol was used as the alkali metal alkoxide and the reaction solvent used as the base, and the raw substrate material of the ester moiety (formula [1] alpha-fluoro ester OR as indicated by constituting the hemiacetal body 2 ) and the like from to. Incidentally, R in the α- fluoroaldehyde equivalent 3 Definition of (alkyl or substituted alkyl groups), R in the formula [2] 2 is the same as, omitted as here.

[0079]

　In the present invention, the "preferred reaction conditions" in the production of α- fluoroaldehyde hereinafter described.

[0080]

　Α- fluoro ester represented by the formula [1] is alpha, an α- difluoro acetic acid esters,
the catalyst is a ruthenium compound, rhodium compound or a platinum compound to a catalyst supported on activated carbon, and, of the catalyst amount, alpha, alpha-difluoro acetic acid esters to be 5 to 30 wt%,
base used is an alkoxide of an alkali metal, and the amount of the alkoxide is alpha, alpha-difluoro acetic acid esters 1 mole from 0.01 to 3 moles,
a alcohol as a reaction solvent, the amount of the alcohol is alpha, alpha-difluoro acetic acid esters 1 mole, and 0.05 ~ 7L,
hydrogen pressure and the aforementioned by employing the reaction temperature, as shown in examples described later, it is possible to obtain the target product with high selectivity.

[0081]

　Moreover, by tilting the equilibrium by addition of any alcohol post-processing, it is possible to replace the alcohol constituting the hemiacetal body with any of ( "any alcohol" is of 1 to 18 carbon atoms, straight chain or branched chain or cyclic (in the case of 3 or more carbon atoms) is of the). Of course, it is possible to obtain a hydrated body by adding the same water.

[0082]

　Post-processing, by employing the common operations in organic synthesis, can be obtained α- fluoro aldehyde of the formula [2]. The post-treatment after the reaction, the crude product (alpha-fluoro aldehyde or alpha-fluoro aldehyde equivalent) is activated carbon treatment as needed, fractional distillation, recrystallization, purification to a high purity by column chromatography or the like can. When the boiling point of the object is low, the reaction-terminated liquid directly operation for recovery distillation is simple. In the reaction in the presence of a base, when the recovery distillation of the relatively acidity high target product (self polymer, hydrated, or hemiacetal thereof, etc.) is a salt or complex such as the base used formed and tend to remain in the pot residue. In such a case, pre-formic acid reaction solution, acetic acid, citric acid, oxalic acid, benzoic acid, methanesulfonic acid, organic acid or hydrogen chloride, such as p-toluenesulfonic acid, hydrogen bromide, nitric acid, such as sulfuric acid can be the target product obtained with good yields by recovery distillation after neutralization with an inorganic acid (recovered washing the bottoms with an organic solvent such as diisopropyl ether is also included).

[0083]

　At post-processing, represented by the general formula [2] of α- fluoro aldehydes, stability equivalent of the aldehyde, especially dimeric derived α- fluoro aldehyde hemiacetal derivatives represented by the general formula [3] the, by contacting an alcohol such as methanol or ethanol, it is also possible purification operation to converge to a hemiacetal of α- fluoro aldehydes.
[Formula 6]

[wherein, R 1 represents a hydrogen atom, a halogen atom or a haloalkyl group, R 4 represents a methyl group or an ethyl group. ]

[0084]

　Incidentally, the catalyst used in the present invention are intended product after the reaction was filtered off and the reaction solution containing α- fluoro aldehyde of the formula [2], after separation of the reaction solution and the catalyst, the catalyst to the reaction residue containing, washed with alcohol such as ethanol, by subsequently recovered can be recycled to the reaction of the present invention.
Example

[0085]

　Hereinafter, the present invention will be described by way of examples more specifically, the present invention is not limited thereto.

[0086]

　The general method of Example and Comparative Examples shown below, also a part of the results are summarized in Table 1.

[0087]

　[Examples 1-12] and [Comparative Examples 1-3]
　A stainless steel (SUS) was charged the following formula:
[Chem 7]

alpha represented by, alpha-predetermined amount of difluoro acetic acid esters (1 eq ), the catalyst (dry product (hereinafter moisture content of 2 wt%), N. E. Ltd. Chemcat) a predetermined quantity (0.002Eq), a predetermined amount of base and (0.25 eq) a predetermined amount of the reaction solvent in addition, the reaction vessel was replaced three times with hydrogen gas, the hydrogen pressure was set to 0.9 MPa, followed by stirring at a predetermined reaction temperature and a predetermined reaction time.
　The reaction solution 19 from the F-NMR analysis, the conversion of the esters, as well as the following formula:
[Chem 8]

alpha indicated by, and stability equivalent of α- difluoro acetaldehyde, excessively reduced following formula:
[ of 9]

beta represented by was calculated selectivity of β- difluoroethanol. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 10]

[0088]

[Table 1]

[0089]

　[Comparative Example 4]
　A stainless steel (SUS) was charged the following formula:
[Chem 11]

alpha represented by, alpha-difluoro acetates 10 g (0.081 mol, 1 eq ), Ru / C 5 wt% (0.12 mmol, 0.002eq, dry goods (hereinafter moisture content of 2 wt%), manufactured by NE Chemcat), sulfuric acid 0.5 g (0.005 mol, 0.06eq) and ethanol 38 mL (2.1 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, the hydrogen pressure was set to 0.9 MPa, the mixture was stirred for 6 hours at 30 ° C.. The reaction solution 19 from the F-NMR analysis, the reaction was found not to proceed.
[Of 12]

[0090]

　Example 13
　A stainless steel (SUS) was charged the following formula:
[Chem 13]

alpha represented by, alpha-difluoro acetates 50 g (0.403 mol, 1eq) , Ru / C 5 wt % (0.62 mmol, 0.002eq, dry goods (water content 2 mass%), manufactured by NE Chemcat), 0.101 of 20% ethanol solution 36.58 g (sodium ethoxide, sodium ethoxide mol, 0.25 eq) and ethanol 202 mL of (2.0 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, and a hydrogen pressure of 3.0 MPa, stirred for 4 hours at 30 ° C. did.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 14]

alpha represented by, alpha-and stability equivalent of difluoro acetaldehyde, excessively reduced following formula:
[Formula 15]

in selectivity of indicated by beta, beta-difluoro ethanol, 50% respectively, 84: was 16. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 16]

[0091]

　Example 14 Additional reactants: a base and a catalyst at the same time added
　to a stainless steel (SUS) was charged the following formula:
[Formula 17]

represented by alpha, alpha-difluoro acetates 10 g (0. 081mol, 1eq), Ru / C 5 wt% (0.12 mmol, 0.002eq, dry goods (hereinafter moisture content of 2 wt%), manufactured by NE Chemcat), 20% sodium ethoxide ethanol solution 6. 89 g (0.020 mol as sodium ethoxide, 0.25 eq) and ethanol 13.3 mL of (6.0 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, 0 hydrogen pressure. set 9 MPa, and stirred for 1 hour at 30 ° C.. Then, hydrogen gas was replaced with nitrogen gas, Ru / C 5 wt% ( 0.12 mmol, 0.002eq), 20% sodium ethoxide ethanol solution 6.89 g (0.020 mol as sodium ethoxide, 0.25 eq) was added and the reaction vessel was replaced three times with hydrogen gas, the hydrogen pressure was set to 0.9 MPa, followed by stirring for 1 hour at 30 ° C.. Similar addition operation (Ru / C 5 wt% ( 0.12 mmol, 0.002eq, dry goods (water content 2% by mass or less), and manufactured by NE Chemcat), ethanol 20% sodium ethoxide solution 6 .89 g (0.020 mol as sodium ethoxide, 0.25 eq) is added operation) was repeated twice.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 18]

alpha indicated by, and stability equivalent of α- difluoro acetaldehyde, excessively reduced following formula:
[Formula 19]

in selectivity of indicated by beta, beta-difluoro ethanol, 79% respectively, was 95: 5. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 20]

[0092]

　Example 15 Additional reactants: catalyst added
　stainless steel (SUS) was charged the following formula:
[Chem 21]

alpha represented by, alpha-difluoro acetates 10 g (0.081mol, 1eq) , Ru / C 5 wt% ( 0.12 mmol, 0.002eq, dry goods (hereinafter moisture content of 2 wt%), manufactured by NE Chemcat), 20% ethanol solution 27.56 g (sodium sodium ethoxide 0.080 mol, 1.00 eq) and ethanol 6.3 mL of (2.4 mol / L) was added as ethoxide, the reaction vessel was replaced three times with hydrogen gas, a hydrogen pressure of 0.9 MPa and it was stirred for 1 hour at 30 ° C.. Then, hydrogen gas was replaced with nitrogen gas, Ru / C 5 wt% of (0.12 mmol, 0.002eq, dry goods (water content 2 mass%), manufactured by NE Chemcat) was added, the reaction vessel the inner was replaced three times with hydrogen gas, the hydrogen pressure was set to 0.9 MPa, followed by stirring for 1 hour at 30 ° C.. Similar addition operation (Ru / C 5 wt% ( 0.12 mmol, 0.002eq) is added operation) was repeated twice.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 22]

alpha indicated by, and stability equivalent of α- difluoro acetaldehyde, excessively reduced following formula:
[Chem 23]

in selectivity of indicated by beta, beta-difluoro ethanol, 82% respectively, 88: was 12. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 24]

[0093]

　Example 16 Additional reactants: bases added
　stainless steel (SUS) to the pressure-proof reaction vessel made of the following formula:
[Chem 25]

alpha represented by, alpha-difluoro acetates 10 g (0.081mol, 1eq) , Ru / C 20 wt% ( 0.48 mmol, 0.008eq, dry goods (hereinafter moisture content of 2 wt%), manufactured by NE Chemcat), 20% ethanol solution 6.89 g (sodium sodium ethoxide 0.020 mol, 0.25 eq) and ethanol 6.3 mL of (2.4 mol / L) was added as ethoxide, the reaction vessel was replaced three times with hydrogen gas, a hydrogen pressure of 0.9 MPa and it was stirred for 1 hour at 30 ° C.. Then, hydrogen gas was replaced with nitrogen gas, was added (0.020 mol, 0.25 eq as sodium ethoxide) 20% ethanol solution 6.89 g of sodium ethoxide, 3 times the reaction vessel with hydrogen gas replacement and the hydrogen pressure was set to 0.9 MPa, followed by stirring for 1 hour at 30 ° C.. Similar addition operation (0.020 mol as a 20% ethanol solution 6.89 g (sodium ethoxide, sodium ethoxide, 0.25 eq) is added operation) was repeated twice.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chemical Formula 26]

alpha represented by, alpha-and stability equivalent of difluoro acetaldehyde, excessively reduced following formula:
[formula 27]

with selectivity of indicated by beta, beta-difluoro ethanol, 77% respectively, 87: was 13. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
Formula 28]

　reaction solution is filtered, neutralized, to obtain an ethanol solution containing the desired product by distillation. Of the ethanol solution 19 was quantified by internal standard method (internal standard substance hexafluorobenzene) by F-NMR analysis, overall yield desired product was about 74%. By performing further fractional distillation, it could be purified to a high purity product (gas chromatography purity of 90% or more).

[0094]

　Example 17 Study of reuse of the catalyst:
　stainless steel (SUS) was charged the following formula:
[Formula 29]

represented by alpha, alpha-difluoro acetates 100 g (0.806 mol, 1eq ), Ru / C 10 wt% (5.0 mmol, 0.006eq, dry goods (water content 2 mass%), manufactured by NE Chemcat), sodium ethoxide 20% ethanol solution 73.16 g ( 0.202 mol as sodium ethoxide, 0.25 eq) and ethanol 202 mL (2.0 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, a hydrogen pressure of 0.9 MPa and stirred for 4 hours at 30 ° C..
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 30]

alpha represented by, alpha-and stability equivalent of difluoro acetaldehyde, excessively reduced following formula:
[Chem 31]

in selectivity of indicated by beta, beta-difluoro ethanol, 47% respectively, 81: was 19. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
　The Ru / C using filtered, washed over with ethanol 200 g. Thereafter recovering the Ru / C and filtered after stirring for 30 minutes with water 200g, filtered after stirring for 30 minutes with ethanol 200g recovered again Ru / C, recovered catalyst the following reaction (Example 16) I was used to.
[Of 32]

[0095]

　Example 18 Study of the reuse of the catalyst
　stainless steel (SUS) was charged the following formula:
[Chem 33]

alpha represented by, alpha-difluoro acetates 100 g (0.806 mol, 1eq) , recovered Ru / C 10 wt% in example 15 (5.0 mmol, 0.006eq), 20% sodium ethoxide ethanol solution 73.16 g (0.202 mol as sodium ethoxide, 0.25 eq) ethanol 202 mL of (2.0 mol / L) was added and the reaction vessel was replaced three times with hydrogen gas, the hydrogen pressure was set to 0.9 MPa, and stirred for 4 hours at 30 ° C..
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 34]

alpha represented by, alpha-and stability equivalent of difluoro acetaldehyde, excessively reduced following formula:
[formula 35]

with selectivity of indicated by beta, beta-difluoro ethanol, 48% respectively, was 80:20. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
　After the reaction described above, it was recovered Ru / C by the same procedure as described in Example 15.
Formula 36]

　Then, using the recovered Ru / C was reacted according to the above scheme, the reaction was carried out again using the further recovered Ru / C. By performing a total of 3 times Ru / C Repeat recovery and reuse, alpha, to give a α- difluoro acetates 300 g (2.4 mol) completion of the reaction solution corresponding to that was subjected to the reaction. Acetate 137g to the reaction-terminated liquid (2.3 mol, 0.95eq) was added directly recovery distillation (oil bath temperature ~ 77 ° C., vacuum degree ~ 2.1 kPa) by the desired product (alpha, alpha- to obtain an ethanol solution containing stabilizing equivalent of difluoro acetaldehyde (ethyl hemiacetal thereof)). Bottoms (solid containing the desired product sodium acetate and unrecovered) ethanol 300mL addition, stirring washed, filtered, the solid washed with ethanol 300mL, recovered again. The filtrate was distilled (oil bath temperature ~ 77 ° C., by the degree of reduced pressure ~ 4.5 kPa) to obtain an ethanol solution containing the desired product. Fractional distillation combined these solutions (10 theoretical plates, distillation temperature 65 ° C., vacuum degree ~ 45 kPa) by the following formula:
[Chem 37]

alpha represented by, alpha-difluoro acetaldehyde stability equivalent of ( to give 180g of ethyl hemiacetal thereof) as a fraction.
　1 H and 19 from F-NMR analysis and gas chromatographic analysis of ethanol in purified products -1 (fraction), beta, beta-difluoro ethanol, alpha, alpha-difluoro-acetaldehyde ethyl hemiacetal of the following formula:
[ of 38]

in β shown, beta-difluoroethyl hemiacetal thereof and the following formula:
[Chem 39]

found that the dimer from ethyl hemiacetal body is contained represented by the respective composition ratios ( mol%) is <5.4%, 0.3% 81.8% 0.2%, was 12.3%. The yield considering the purity was about 59%. It obtained the ethyl hemiacetal body, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
　Β contained in the purified products -1, relative to the sum of the dimer derived from the ethyl hemiacetal thereof with β- difluoroethyl hemiacetal thereof, ethanol was added 1.8 eq, stirred for 2 hours at 30 ° C., purified products It was obtained -2. Of purified product -2 1 H and 19 from F-NMR analysis, beta, beta-difluoro ethanol, alpha, alpha-ethyl hemiacetal of difluoro acetaldehyde, beta, beta-difluoroethyl hemiacetal body and from ethyl hemiacetal body the purity of the dimer, 0.2% respectively 83.2%, 0.1% and 8.2%. Further, the content of ethanol was 8.7%. This action, beta, beta-content difluoroethyl hemiacetal body and ethyl hemiacetal-derived dimeric can be reduced, it is possible to improve the content of the desired alpha, alpha-difluoro-acetaldehyde ethyl hemiacetal body It was.
　In addition to the above, the low boiling components of the removal of less relative coexistence of ethanol performed until (in particular less than 4.0 wt%) made, remarkably the content of dimers from ethyl hemiacetal body there is a case to be increased. For example, beta, beta-difluoro ethanol, alpha, alpha-ethyl hemiacetal of difluoro acetaldehyde, beta, beta-purity difluoroethyl hemiacetal body and ethyl hemiacetal-derived dimeric, 0.6% respectively, 76.2%, 1.4%, was 18.1% (content of ethanol was 3.8%). Even in such a case, as described above, beta, ethanol 1.8 eq. Added to the sum of the dimers derived from β- difluoroethyl hemiacetal body and ethyl hemiacetal thereof, 2 hours at 30 ° C. by employing a purification operation of stirring, 0.8%, respectively, 79.39%, 0.4%, it could be converged to 10.9% (content of ethanol 8.9%).
　alpha, alpha-ethyl hemiacetal of difluoro acetaldehyde, beta, beta-difluoro-ethyl hemiacetal body and dimer from ethyl hemiacetal body, 1 H and 19 shows the assignment of F-NMR analysis below.
[Alpha, alpha-difluoro-acetaldehyde ethyl hemiacetal body]
1 H-NMR (reference material; Me 4 Si, deuterated solvent; CDCl 3 ), [delta] ppm; 1.26 (t, 3H), 3.63 (m, 1H), 3.92 (m, 1H ), 4.70 (m, 1H), 5.60 (dt, 1H), protons of hydroxyl groups can not be assigned.
19 F-NMR (reference material; C 6 F 6 , deuterated solvent; CDCl 3 ), [delta] ppm; 27.9 (ddd, 2F).
[Beta, beta-difluoroethyl hemiacetal body]
1 H-NMR (reference material; Me 4 Si, deuterated solvent; CDCl 3 ), [delta] ppm; 3.92 (m, 2H), 4.79 (m, IH) , 5.68 (dt, 1H), 5.91 (ddt, 1H), protons of hydroxyl groups can not be assigned.
19 F-NMR (reference material; C 6 F 6 , deuterated solvent; CDCl 3 ), [delta] ppm; 27.0 (ddd, 2F), 36.1 (dt, 2F).
[Ethyl hemi dimer from acetalized]
1 H-NMR (reference material; Me 4 Si, deuterated solvent; CDCl 3 ), [delta] ppm; 1.28 (t, 3H), 3.67 (m, IH) , 3.88 (m, 1H), 4.78 (m, 0.5H), 4.90 (m, 0.5H), 5.04 (m, 1H), 5.64 (m, 2H), protons of hydroxyl groups can not be assigned.
19 F-NMR (reference material; C 6 F 6 , deuterated solvent; CDCl 3 ), [delta] ppm; 27.9 (m, 4F).

[0096]

　Substrate Change Example 19 starting material
　in stainless steel (SUS) was charged the following formula:
[Chem 40]

alpha represented by, alpha-difluoro acetates 50 g (0.454 mol, 1eq) , ru / C 5 wt% (0.62 mmol, 0.001eq, dry goods (water content 2 mass%), manufactured by NE Chemcat), 28% methanol solution 21.90 g (sodium methoxide sodium methoxide 0.114 mol as de, 0.25 eq) and methanol 190 mL of (2.4 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, and a hydrogen pressure of 0.9 MPa, 30 and the mixture was stirred for 6 hours at ℃.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 41]

alpha indicated by, and stability equivalent of α- difluoro acetaldehyde, excessively reduced following formula:
[Chem 42]

in selectivity of indicated by beta, beta-difluoro ethanol, 22% respectively, was 100: 0. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 43]

[0097]

　Example 20 Substrate changing the starting material
　in stainless steel (SUS) was charged the following formula:
[Chem 44]

trifluoroacetate esters 50 represented by g (0.352 mol, 1eq), Ru / C 5 wt% (0.62 mmol, 0.002eq , dry goods (water content 2 mass%), manufactured by NE Chemcat), as a 20% ethanol solution 29.77 g (sodium ethoxide, sodium ethoxide 0 .088 mol, 0.25eq) and ethanol 190 mL of (1.8 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, and a hydrogen pressure of 0.9 MPa, 6 at 30 ° C. time and the mixture was stirred.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 45]

and stability equivalent of trifluoroacetaldehyde represented by excessively reduced following formula:
[Chem 46]

tri represented by selectivity of trifluoroethanol are 38%, respectively, was 99: 1. Stability equivalent of trifluoroacetaldehyde obtained are, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 47]

[0098]

　Example 21 Substrate changing the starting material
　in stainless steel (SUS) was charged the following formula:
[Chem 48]

trifluoroacetate esters 50 represented by g (0.390 mol, 1eq), Ru / C 5 wt% (0.62 mmol, 0.002eq , dry goods (water content 2 mass%), manufactured by NE Chemcat), as a 28% methanol solution of 18.81 g (sodium methoxide, sodium methoxide 0 .096 mol, 0.25eq) and methanol 190 mL of (2.1 mol / L) was added, the reaction vessel was replaced three times with hydrogen gas, and a hydrogen pressure of 0.9 MPa, stirred for 6 hours at 30 ° C. did.
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 49]

and stability equivalent of trifluoroacetaldehyde represented by excessively reduced following formula:
[Chem 50]

bird represented by selectivity of trifluoroethanol are 27%, respectively, was 99: 1. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
Formula 51]

[0099]

　Example 22
　Stainless steel (SUS) pressure-proof reaction vessel, the following formula:
[Chem 52]

alpha represented by, alpha-difluoro acetates 100 g (0.806 mol, 1eq) , Ru / C 10 wt % (5.0 mmol, 0.006eq, dry goods (hereinafter moisture content of 2 wt%), manufactured by NE Chemcat), 0.202 of 20% ethanol solution 73.16 g (sodium ethoxide, sodium ethoxide mol, 0.25 eq) and ethanol 202 mL of (2.0 mol / L) was added and after confirming that it is 0.18% by measuring the water in the system by Karl Fischer, the reaction vessel with hydrogen gas substituted three times, the hydrogen pressure was set to 0.9 MPa, and stirred for 4 hours at 30 ° C..
　The reaction solution 19 from the F-NMR analysis, the conversion rate, the following formula:
[Chem 53]

alpha indicated by, and stability equivalent of α- difluoro acetaldehyde, excessively reduced following formula:
[Chem 54]

in selectivity of indicated by beta, beta-difluoro ethanol, 69% respectively, was 98: 2. The resulting alpha, stable equivalent of α- difluoro acetaldehyde, 1 H and 19 was consistent with the preparation in F-NMR analysis and gas chromatography.
[Of 55]

Industrial Applicability

[0100]

　α- fluoro aldehydes obtained by the process of the present invention can be utilized as pharmaceutical and agrochemical intermediates.

The scope of the claims

[Claim 1]

The α- fluoroester represented by the general formula [1], ruthenium compound, rhodium compound or catalyst platinum compound supported on a metal oxide or activated carbon, and, in the presence of a base, the hydrogen (H 2 are reacted) it makes the method of producing the α- fluoro aldehydes represented by general formula [2].
Formula 56]

wherein, R 1 represents a hydrogen atom, a halogen atom or a haloalkyl group, R 2 represents an alkyl group or a substituted alkyl group. ]
[Chemical Formula 57]

wherein, R 1 has the formula [1] the same as. ]

[Claim 2]

Base is imine base or an inorganic base A process according to claim 1.

[Claim 3]

The base is alkoxide of alkali metal A method according to claim 1 or 2.

[Claim 4]

The reaction is carried out by adding a base or catalyst sequential method according to any one of claims 1 to 3.

[Claim 5]

The amount of the base is, the general formula [1] shown by α- fluoroester 1 mol per 0.01 mol or more and 3 mol or less, The method according to any one of claims 1 to 4.

[Claim 6]

Successive addition performs the base is divided into at least twice, The method of claim 4.

[Claim 7]

Successive addition performs catalyst was divided into at least twice, The method of claim 4.

[8.]

Ruthenium compounds, fluorides of ruthenium, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride, to any one of claims 1 to 7 the method described.

[Claim 9]

Rhodium compounds, fluorides rhodium, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride, to any one of claims 1 to 7 the method described.

[Claim 10]

Platinum compounds, fluorides of platinum, chloride, fluoride chloride, oxyfluoride, oxychloride, and at least one selected from the group consisting of oxyfluorides chloride, to any one of claims 1 to 7 the method described.

[Claim 11]

Metal oxide is alumina, zirconia, titania, silica or magnesia, A method according to any one of claims 1 to 7.

[Claim 12]

In the range of hydrogen pressure is 0.001 ~ 4 MPa, and, in a range of 0 ~ 40 ° C. as a reaction temperature, method according to any one of claims 1 to 11.

[Claim 13]

The reaction is carried out in the presence of an alcohol, The method according to any one of claims 1 to 12.

[Claim 14]

After completion of the reaction, recovering the catalyst used is carried out by recycling method according to any one of claims 1 to 13.

[Claim 15]

Catalyst recovery, the catalyst was filtered off, carried out by washing with water and then an alcohol The method of claim 14.

[Claim 16]

Water in the reaction system and carrying out in a range of 0.5 to 0.001 wt% A method according to any of claims 1 to 15.

[Claim 17]

Α- fluoroaldehyde of the formula [2], comprising obtaining as α- fluoroaldehyde equivalents represented by the following formula The method according to any one of claims 1 to 16.
Formula 58]

wherein, R 1 is R in the general formula [1] 1 are the same as. R 3 represents an alkyl group or a substituted alkyl group. ]