JPS6154783B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a urethane compound. More specifically, the present invention relates to a method for producing a urethane compound by reacting a urea compound with carbon monoxide and an organic hydroxyl compound in the presence of an oxidizing agent to oxidatively carbonylate it. Urethane compounds are important compounds used in carbamate pesticides and the like, and recently there has been a demand for an inexpensive method for producing them as raw materials for producing isocyanates without using phosgene. As a method for producing such urethane compounds using carbon monoxide, aromatic nitro compounds,
A method of reductively urethanizing an aromatic nitroso compound, an aromatic azo compound, an aromatic azoxy compound, etc. in the absence of an oxidizing agent, and a method of oxidatively urethanizing an aromatic amino compound are known. Furthermore, a method of oxidatively converting N·N'-diarylurea into urethane has also been proposed (Japanese Patent Application Laid-open No. 1983-1999-
Publication No. 120552). In this method, a group noble metal or its compound is used as the main catalyst, and a metal capable of carrying out a redox reaction in the reaction system, such as copper chloride, iron chloride, iron oxychloride, vanadium chloride, vanadium oxychloride, etc., is used as a promoter. It is necessary to dissolve the chloride in the reaction system. However, these dissolved metal chlorides are highly corrosive to metal materials such as reaction vessels, piping, valves, etc., and therefore there is an equipment problem in that expensive metal materials must be used.
Furthermore, when producing aromatic urethane, separating and recovering these dissolved metal chlorides from high-boiling substances such as the aromatic urethane product requires complicated operations and a large amount of cost. There was a drawback that it was necessary. In order to overcome these drawbacks, the present inventors have conducted intensive research on a method for producing urethane compounds by oxidatively urethanizing urea compounds. We have discovered a completely new catalyst system that allows the reaction to proceed catalytically without using the chloride of an element that performs a redox reaction, and based on this knowledge, we have completed the present invention. That is, in the present invention, in producing a urethane compound by reacting a urea compound with carbon monoxide and an organic hydroxyl compound in the presence of an oxidizing agent,
(a) at least one selected from platinum group metals and compounds containing platinum group elements, and (b) at least one halogen selected from chlorine, bromine, and iodine.
and (c) at least one selected from basic substances.
The present invention provides a method for producing a urethane compound characterized by using a catalyst system comprising a species. As described above, a major feature of the present invention is that at least one selected from platinum group metals and compounds containing platinum group elements, at least one selected from chlorine, bromine, and iodine, It is a catalyst system that combines at least one kind selected from basic substances, and by using this catalyst system, a urethane compound can be obtained from a urea compound with good selectivity and in high yield. be. These facts are completely unknown and truly surprising, and could not have been expected from the prior art mentioned above (Japanese Patent Application Laid-open No. 120552/1983). That is, in the prior art, a catalyst system is used in which a platinum group compound is used as a main catalyst and a chloride of an element capable of carrying out a redox reaction is used as a co-catalyst. is a combination of palladium chloride and iron oxychloride. In such a system, divalent palladium is involved in the reaction, and as the reaction progresses, it is reduced to zero-valent palladium, which is reoxidized by trivalent iron oxychloride to divalent palladium. At the same time, trivalent iron is reduced to divalent iron, and this divalent iron is further oxidized by an oxidizing agent and returned to trivalent iron. It is thought that the product is a urethane compound. As described above, it has been shown that in the prior art methods, the chloride of an element having a redox effect is essential as a reoxidizing agent for the main catalyst in the reaction system. Elements that have such a function are those that can undergo redox reactions selected from the elements of groups a to a and groups b to b of the periodic table, and specifically include copper, zinc, and mercury. , thallium, tin, titanium, arsenic, antimony, bismuth, vanadium, chromium, molybdenum, tungsten-manganese, iron, cobalt, and nickel, among which copper, vanadium, manganese, molybdenum, tungsten, antimony, and iron Only those examples are described in the Examples. In contrast, the method of the present invention uses a halogen or a combination of a halogen and a basic substance, does not use any acidic substances such as Lewis acids, and uses a metal capable of performing a redox reaction in the reaction system. It does not require any elements at all. Therefore, it is presumed that the reaction of the present invention proceeds by a completely different reaction mechanism from the reactions described in the prior art. Although it is unclear how the combination of halogen and basic substance used in the method of the present invention acts in this reaction, it is possible to combine it with a platinum group metal or a compound containing a platinum group element. It is clear that it plays an important role as a catalyst component in the oxidative urethanization reaction of urea compounds. In other words, when only a platinum group metal or a compound containing a platinum group element is used, under the conditions of this reaction, the urethanization reaction hardly progresses, or even if it does proceed, only a small amount of urethane is produced. When only platinum group elements in the state are used, hardly any urethane compounds can be obtained. For example, palladium is one of the effective catalyst components for this reaction, but the reaction hardly progresses if only palladium black, which is zero-valent metal palladium, is used alone. However, the present inventors discovered that when a halogen such as iodine is added to this, the reaction proceeds catalytically, and when a basic substance such as cesium hydroxide is further added to this system, a urethane compound can be obtained almost quantitatively. You will be able to do it. In this way, in the method of the present invention, a solid platinum group compound in a metallic state can also be used as one of the catalyst components, which means that the expensive platinum group compound can be separated from the reaction system by a simple method such as filtration. , it has been shown that it can be recovered, which is industrially advantageous. In addition, when a solid platinum group compound in a metallic state is used, if a Lewis acid such as ferric chloride used in the prior art coexists, the platinum group compound will be eluted into the solution by these acids. Sometimes,
One of the major features of the present invention is that these platinum group compounds do not substantially elute in the reaction system of the present invention.
It is one. Another major feature of the present invention is that it uses a halogen and a basic substance, and the halogen and basic substance can be easily separated and recovered from the product. Unlike heavy metal chlorides, they do not mix into products as contaminants. The platinum group metal and platinum group element-containing compound used in the method of the present invention may contain at least one component selected from platinum group elements such as palladium, rhodium, platinum, ruthenium, iridium, and osmium. There are no particular limitations on these elements, and these elements may be in a metallic state or may be components forming a compound. In addition, these catalyst components include activated carbon, graphite,
Silica, alumina, silica - alumina, silica -
It may be supported on a carrier such as titania, titania, zirconia, barium sulfate, calcium carbonate, asbestos, bentonite, diatomaceous earth, polymer, ion exchange resin, zeolite, molecular sieve, magnesium silicate, magnesia, etc. . Examples of platinum group elements in the metallic state include metals such as palladium, rhodium, platinum, ruthenium, iridium, and osmium, these metal blacks, and catalyst components containing these metal ions on the above-mentioned carrier, and then hydrogen and Those reduced with formaldehyde, alloys or intermetallic compounds containing these metals, etc. are used. Further, the alloy or intermetallic compound may be one of these platinum group metals, or it may be one of these platinum group metals, or it may contain other elements such as selenium, tellurium, sulfur, antimony, bismuth,
Copper, silver, gold, zinc, tin, vanadium, iron, cobalt nickel, mercury, lead, thallium, chromium,
It may also contain molybdenum, tungsten, or the like. On the other hand, compounds containing platinum group elements include, for example, inorganic salts such as halides, sulfates, nitrates, phosphates, and borates; organic acid salts such as acetates, oxalates, and formates; and cyanides. ; Hydroxides; Oxides; Sulfides; Nitro group, cyano group,
Complex compounds of metals such as metal salts containing anions such as halogens and oxalate ions, and salts or complexes containing ammonia, amines, phosphines, carbon monoxide, chelate ligands, etc.; organic ligands or organic Examples include organometallic compounds having groups. Among these catalyst components, those containing palladium or rhodium or both are particularly preferred, such as Pd black; Pd black;
-C, Pd- _Al2O3 , Pd- _SiO2 , _Pd - _TiO2 , Pd-
Supported palladium catalysts such as ZrO ₂ , Pd-BaSO ₄ , Pd-CaCO ₃ , Pd-asbestos, Pd-zeolite, Pd-molecular sieve; Pd-Pb, Pd-
Be, Pd-Te, Pd-Hg, Pd-Tl, Pd-P, Pd-
Cu, Pd−Ag, Pd−Fe, Pd−Co, Pd−Ni, Pd−
Alloys or intermetallic compounds such as Rh; and these alloys or intermetallic compounds supported on the above-mentioned carriers; PdCl ₂ , PdBr ₂ , PdI ₂ , Pd
(NO ₃ ) ₂ , PdSO ₄ and other inorganic salts; Pd
(OCOCH ₃ ) ₂ , organic acid salts such as palladium oxalate; Pd(CN) ₂ ; PdO; PdS; M ₂ [PdX ₄ ], M ₂
Palladate salts represented by [PdX ₆ ] (M represents an alkali metal or ammonium ion,
X represents a nitro group, a cyano group, or a halogen. ); Ammine complexes _of palladium such as [Pd(NH ₃ ) _{4 ]} X ₂ , [Pd(en) ₂ ] ) ₂ , PdCl ₂ (PR ₃ ) ₂ , Pd
(CO)( _PR3 ) ₃ , Pd( _PPh3 ) ₄ , PdCl(R)
(PPh ₃ ) ₂ , Pd(C ₂ H ₄ )(PPh ₃ ) ₂ , Pd(C ₃ H ₅ ) ₂ and other complex compounds or organometallic compounds (R represents an organic group); Pd(acac) ₂ Complex compounds coordinated with chelate ligands such as Rh black; Supported rhodium catalysts similar to Pd; Rh alloys or intermetallic compounds similar to Pd, and those supported on supports; RhCl ₃
and hydrates, RhBr ₃ and hydrates, RhI ₃ and hydrates, Rh ₂ (SO ₄ ) ₃ and inorganic salts such as hydrates; Rh ₂
(OCOCH ₃ ) ₄ ; Rh ₂ O ₃ , RhO ₂ ; M ₃ [RhX ₆ ] and hydrates (M and X have the same meanings as above); [Rh
Rhodium ammine complexes such as ( _NH3 ) ₅ ] _X3 , [Rh(en) ₃ ] _X3 ; Rhodium carbonyl clusters such as _Rh4 (CO) ₁₂ , _Rh6 (CO) ₁₆ ;
(CO) ₂ ] ₂ , RhCl ₃ (PR ₃ ) ₃ , RhCl (PPh ₃ ) ₃ , RhX
(CO)L ₂ (R, X have the same meanings as above, L
is a ligand consisting of an organic phosphorus compound and an organic arsenic compound), a complex compound such as RhH(CO)(PPh ₃ ) ₃ , or an organometallic compound. In the present invention, only one type of these platinum group metals or compounds containing platinum group elements may be used, or two or more types may be used as a mixture, and there is no particular restriction on the amount used. Normally, components containing platinum group elements are 0.0001 to 50% relative to urea compounds.
A range of mole % is desirable. The basic substance used in the present invention may be either inorganic or organic, and includes, for example, lithium oxide, lithium peroxide, sodium oxide, sodium peroxide, sodium superoxide, potassium oxide, potassium peroxide, Dipotassium trioxide, potassium superoxide, rubidium oxide, rubidium peroxide,
Dirubidium trioxide, rubidium superoxide, rubidium ozonide, cesium oxide, cesium peroxide,
Alkali metal oxides such as dicesium trioxide, cesium superoxide, and cesium ozonide; alkalis such as beryllium oxide, magnesium oxide, calcium oxide, calcium peroxide, strontium oxide, strontium peroxide, barium oxide, and barium peroxide Earth metal oxides; alkalis such as lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, etc. hydroxides of metals and alkaline earth metals;
Salts of strong bases and weak acids such as sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, barium carbonate, sodium silicate, magnesium silicate, potassium aluminate, calcium aluminate, sodium borate, barium borate; carbonization Carbides such as calcium and cesium carbide; Hydroxides and oxides of aluminum group metals such as aluminum hydroxide, potassium hydroxide, isodium hydroxide, thallium hydroxide, and thallium oxide; Lanthanum oxide, cerium oxide, and cerium hydroxide oxides and hydroxides of rare earth elements such as; lithium hydride;
Hydrides such as sodium hydride, borothotrium hydride, calcium hydride, lithium aluminum hydride; sulfides and hydrogen sulfides of alkali metals or alkaline earth metals such as sodium sulfide, sodium hydrogen sulfide, potassium sulfide, calcium sulfide, etc. quaternary ammonium hydroxide compounds such as tetraethylammonium hydroxide and tetrapropylammonium hydroxide; quaternary phosphonium hydroxide compounds such as methyltriphenylphosphonium hydroxide and tetrabutylphosphonium hydroxide;
Tertiary sulfonium hydroxide compounds such as triethylsulfonium hydroxide and triphenylsulfonium hydroxide; salts of strong bases and weak organic acids such as sodium acetate, potassium benzoate, lupidium oxalate, and barium propionate; sodium methylate; Alkali metal and alkaline earth metal alcoholates such as sodium ethylate and calcium ethylate; alkali metal and alkaline earth metal phenolates such as sodium phenolate, potassium phenolate and magnesium phenolate; lithium amide, sodium amide, Amides of alkali metals and alkaline earth metals such as calcium amide and lithium dimethylamide;
trimethylamine, triethylamine, tri-n
-Butylamine, triphenylamine, diethylmethylamine, N・N-diethylaniline, N-
Methylpiperidine, N・N′-diethylpiperazine, N-methylmorpholine, triethylenediamine, hexamethylenetetramine, N・N・N′・
N'-tetramethylethylenediamine, dicyclohexylethylamine, 1,2,2,6,6-pentamethylpiperidine, pyridine, quinoline, phenanthroline, indole, N-methylimidazole, 1,8-diazabicyclo-[5,4,
0]-undecene-7 (DBU), 1,5-diazabicyclo-[4.3.0]-nonene-5 (DBN)
tertiary amines such as cyclic nitrogen-containing compounds (however, N
-H group); Crown compounds such as crown ether, aza crown ether, thia crown ether, aza crown, and complexes of these crown compounds with alkali metals, alkaline earth metal ions, etc. are used. It will be done. Furthermore, these basic groups have 2 groups in the molecule.
There may be more than one, or it may form a part of a polymer such as an anion exchange resin having a quaternary ammonium hydroxide group. Further, these basic substances or groups having basicity may be supported on a solid or chemically bonded. These basic substances may be used alone or
Alternatively, two or more types may be mixed and used. Further, as for the halogens, only one kind of chlorine, bromine, and iodine may be used, or two or more kinds of halogens may be used as a mixture.
Among the halogens, bromine and iodine are preferred;
Iodine is particularly preferred. The amount of halogen and basic substance used in the present invention is not particularly limited, but the amount of halogen is usually in the range of 0.001 to 10,000 times the amount of the metal element in the component containing the platinum group element used. It is preferable to use the basic substance in a molar amount of 0.01 to 1000 times that of the halogen. The urea compound used as a raw material in the present invention has the formula A compound containing at least one urea bond in one molecule as shown in Here, the two lines connected to N represent bonds between the nitrogen atom and other atoms or groups. Such atoms or groups include hydrogen, alkali metal atoms, hydroxyl groups, amino groups, aliphatic groups, alicyclic groups, araliphatic groups, heterocyclic groups, and aromatic groups. In addition, these nitrogens themselves may be elements constituting a ring,
The urea bond itself may be a part of the ring. Such urea compounds may be unsubstituted urea, monosubstituted urea, disubstituted urea, trisubstituted urea, tetrasubstituted urea, or the like. Examples of monosubstituted ureas include aliphatic monosubstituted ureas such as methylurea, ethylurea, propylurea, butylurea, and hexylurea; alicyclic monosubstituted ureas such as cyclopropylurea, cyclobutylurea, and cyclohexylurea; benzyl Aroaliphatic monosubstituted ureas such as urea and β-phenethylurea; heterocyclic monosubstituted ureas such as furanylurea and thiophenyl urea; aromatic monosubstituted ureas such as phenyl urea, tolylurea and naphthylurea, etc. are used. It will be done. Examples of the disubstituted urea include N·N-dimethylurea, N·N-diethylurea, N·N-dipropylurea, N·N-dibutylurea, N·N-dihexylurea, and N-ethyl-N-methylurea. , N-
Aliphatic N/N-disubstituted ureas such as ethyl-N-butyl urea; N/N-dicyclopropylurea, N.
N-dicyclobutylurea, N·N-dicyclohexylurea; Alicyclic N·N-disubstituted ureas such as N-cyclopropyl-N-methylurea, N-cyclohexyl-N-ethylurea; N·N-dibenzylurea , Aroaliphatic N・N-disubstituted ureas such as N-benzyl-N-methylurea; Heterocyclics such as N・N-difuranylurea, N・N-dithiophenylurea, N-furanyl-N-methylurea N/N-disubstituted ureas; N/N-diphenylurea, N/N-ditolyl urea, N/N-dinaphthylurea, N-phenyl-N-methylurea, N-phenyl-N-tolylurea, N- Aromatic N, such as naphthyl-N-benzylurea, N-phenyl-N-cyclohexylurea, etc.
N-disubstituted ureas; N・N'-dimethylurea,
N・N′-diethylurea, N・N′-dipropylurea, N・N′-dibutylurea, N・N′-dihexylurea, N-ethyl-N′-methylurea, N-ethyl-N′-butyl Aliphatic N/N'-disubstituted ureas such as urea and N-hexyl-N'methylurea;
N・N′-dicyclopropylurea, N・N′-dicyclobutylurea, N・N′-dicyclohexylurea, N-cyclopropyl-N′-methylurea, N
-Alicyclic N/N'-disubstituted ureas such as cyclohexyl-N'-ethylurea; Aroaliphatic N/N'- such as N/N'-dibenzylurea and N-benzyl-N'-methylurea Disubstituted ureas; Heterocyclic N/N'-disubstituted ureas such as N/N'-difuranylurea, N/N'-dithiophenyl urea; N/N'-diphenylurea, N/N'-ditolyl urea , N.N'-dinaphthylurea, N-phenyl-N'-tolylurea,
Aromatic N/N'-disubstitution such as N-phenyl-N'-naphthylurea, N-phenyl-N'-ethylurea, N-naphthyl-N'-benzylurea, N-phenyl-N'-cyclohexylurea, etc. Ureas and ureas of cyclic nitrogen compounds such as piperidyl urea and pyrrolidinyl urea are used. Examples of trisubstituted ureas include trimethylurea, triethylurea, tripropylurea, tributylurea, trihexylurea, N·N-dimethyl-N′-ethylurea, N·N-diethyl-N′-butylurea, N-
Aliphatic trisubstituted ureas such as methyl-N-ethyl-N'-butylurea; tricyclopropylurea, tricyclohexylurea, N.N'-dicyclohexyl-N'-methylurea, N-cyclohexyl-
Alicyclic trisubstituted ureas such as N-ethyl-N'-butylurea and N·N-diethyl-N'-cyclobutylurea; such as trifuranylurea, trithiophenylurea, N·N'-difuranyl-N-methylurea, etc. Heterocyclic trisubstituted ureas; triphenylurea, tritolylurea, trinaphthylurea, N·N-diphenyl-N'-methylurea, N·N'-diphenyl-N-cyclohexylurea, N·N-dimethyl-
Aromatic trisubstituted ureas such as N'-phenyl urea and N-phenyl-N-ethyl-N'-benzylurea; N-substituted cyclic nitrogen compounds such as N-ethylpiperidylurea and N-methylpyrrolidinyl urea Ureas and the like are used. Examples of tetra-substituted ureas include aliphatic tetra-substituted ureas such as tetramethylurea, tetraethylurea, tetrapropylurea, tetrahexylurea, diethyldimethylurea, and ethyltrimethylurea;
Alicyclic tetra-substituted ureas such as tetracyclopropyl urea, tetracyclohexyl urea, dicyclohexyl diethyl urea, and cyclobutyl trimethyl urea; aromatic aliphatic tetras such as tetrabenzyl urea, tribenzyl methyl urea, dibenzyl diethyl urea, benzyl trimethyl urea, etc. Substituted ureas; Heterocyclic tetra-substituted ureas such as tetrafuranylurea, tetrathiophenylurea, furanyltrimethylurea; tetraphenylurea, tetratolylurea, tetranaphthylurea, methyltriphenylurea, diethyldiphenylurea, dicyclohexyldiphenyl Aromatic tetra-substituted ureas such as urea and naphthyltriethylurea are used. Examples of cyclic urea compounds having a urea bond as a ring component include 2-imidazolone, 2-imidazolidone,
Biotin, hydantoin, N·N'-hexamethylene urea, parabanic acid, benzimidazolidone, etc. are used. Furthermore, compounds having two or more urea bonds in the molecule, such as polyureas of polyamines such as N.N'-dimethylcarbamoylhexamethylenediamine and N.N'-diphenylcarbamoylphenylenediamine, or compounds represented by the following formula. Polymeric ureas having a structural unit such as that described above can also be used. In addition, in these substituted ureas, one of the substituents
or more hydrogen may be substituted with other substituents, such as lower aliphatic groups, amino groups, carboxyl groups, ester groups, alkoxy groups, cyano groups, halogens, nitro groups, urethane groups, sulfoxide groups, sulfone groups, carbonyl groups, and amide groups. , an aromatic group, an araliphatic group, or the like. In order to obtain a urethane compound as a raw material for producing isocyanates, N.N'-disubstituted ureas are preferable, and aromatic urethane compounds are particularly preferred.
It is easily produced using N'-diarylureas. One or more of these urea compounds may be used. The organic hydroxyl compound used in the present invention is 1
or polyvalent or polyhydric alcohols, or monovalent or polyvalent phenols. Examples of such alcohols include linear or branched monovalent or polyhydric alkanols and alkenols having 1 to 20 carbon atoms. ,
Examples include monovalent or polyvalent cycloalkanols, cycloalkenols, and aralkyl alcohols. Furthermore, these alcohols may contain other inert substituents, such as halogen atoms, cyano groups, alkoxy groups, sulfoxide groups, sulfone groups, carbonyl groups, ester groups, and amide groups. Specific examples of such alcohols include methanol, ethanol, propanol (each isomer), butanol (each isomer), pentanol (each isomer), hexanol (each isomer), heptanol (each isomer), Octanol (each isomer), Nonyl alcohol (each isomer), Decyl alcohol (each isomer), Undecyl alcohol (each isomer), Lauryl alcohol (each isomer), Tridecyl alcohol (each isomer), Tetra Aliphatic alcohols such as decyl alcohol (each isomer) and pentadecyl alcohol (each isomer); cycloalkanols such as cyclohexanol and cycloheptanol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether,
Alkylene glycol monoethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether; ethylene glycol, propylene glycol, diethylene glycol, dipropylene Polyhydric alcohols such as glycol, glycerin, hexanetriol, and trimethylolpropane; aralkyl alcohols such as benzyl alcohol are used. Examples of phenols that can be used include phenol, various alkylphenols, various alkoxyphenols, various halogenated phenols, dihydroxybenzene, 4,4'-dihydroxy-diphenylmethane, bisphenol-A, and hydroxynaphthalene. The oxidizing agent used in the present invention may be any conventional oxidizing agent, but preferred are molecular oxygen, organic nitro compounds, or mixtures thereof. Particularly preferred is molecular oxygen. This molecular oxygen is pure oxygen or a substance containing oxygen, which may be air, or other gases that do not inhibit the reaction of air or pure oxygen, such as nitrogen,
It may be diluted by adding an inert gas such as argon, helium, or carbon gas. In some cases, it may also contain gases such as hydrogen, carbon monoxide, hydrocarbons, and halogenated hydrocarbons. Further, the organic nitro compound may be any of alicyclic, aliphatic, and aromatic nitro compounds. Examples of alicyclic nitro compounds include nitrocyclobutane, nitrocyclopentane, nitrocyclohexane, dinitrocyclohexane (each isomer), bis-(nitrocyclohexyl)-methane, and examples of aliphatic nitro compounds include nitromethane, nitroethane, Nitropropane (each isomer), Nitrobutane (each isomer), Nitropentane (each isomer), Nitrohexane (each isomer),
Nitrodecane (each isomer), 1,2-dinitroethane, dinitropropane (each isomer), dinitrobutane (each isomer), dinitropentane (each isomer), dinitrohexane (each isomer), dinitrodecane (each Aromatic nitro compounds include, for example, nitrobenzene, dinitrobenzene (isomers), nitrotoluene (isomers), phenylnitromethane, bis-(nitromethyl)-cyclohexane, bis-(nitromethyl)-benzene, etc. , dinitrotoluene (each isomer), nitropyridine (each isomer), dinitropyridine (each isomer), nitronaphthalene (each isomer), dinitronaphthalene (each isomer), and the like. In addition, in these nitro compounds, at least one hydrogen has another substituent, such as a halogen atom, an amino group, a cyano group, an alkyl group, an alicyclic group, an aromatic group, an aralkyl group, an alkoxy group, a sulfoxide group, It may be substituted with a sulfone group, carbonyl group, ester group, amide group, etc. In the present invention, when the oxidizing agent is molecular oxygen,
The reaction proceeds according to the following general reaction formula. (Here, R ¹ , R ² , R ³ , and R ⁴ are hydrogen, alkali metal atoms, hydroxyl groups, amino groups, aliphatic groups, alicyclic groups, araliphatic groups, heterocyclic groups, and aromatic groups. (R represents an organic group.) Molecular oxygen may be present in less or more than equivalent amounts, but mixtures of oxygen/carbon monoxide or oxygen/organic hydroxyl compounds are outside the explosive limits. should be used in In addition, when an organic nitro compound is used as an oxidizing agent, the organic nitro compound itself also participates in the reaction and becomes urethane, so if the structure of the organic group is different from the substituent of the urea compound, the urethane compound depending on the structure It goes without saying that the same urethane compound can be obtained if both structures are the same. In this case, the urethanization reaction proceeds according to the following reaction formula, for example. (Here, R ¹ , R ² , R ³ , R ⁴ and R have the same meanings as above, and R ⁵ represents an organic residue of an organic nitro compound.) When only an organic nitro compound is used as an oxidizing agent, urea The quantitative ratio of the compound to the organic nitro compound is preferably 1 mole of nitro group per 2 moles of urea group, but of course it may be carried out at a value deviating from this stoichiometric ratio. Generally, the equivalent ratio of urea groups to nitro groups is carried out from 1.1:1 to 4:1, preferably from 1.5:1 to 2.5:1. Of course, if molecular oxygen or other oxidizing agents are used at the same time, the amount of organic nitro compound may be less than the stoichiometric amount. In the method of the present invention, it is preferable to use an excess of the organic hydroxyl compound as the reaction solvent, but if necessary, a solvent that does not adversely affect the reaction can also be used. Examples of such solvents include aromatic hydrocarbons such as benzene, toluene, xylene, and mesitylene; halogenated aromatics such as chlorobenzene, dichlorobenzene, trichlorobenzene, fluorobenzene, chlorotoluene, chlornaphthalene, and bromnaphthalene. Hydrocarbons; halogenated aliphatic hydrocarbons or halogenated alicyclic hydrocarbons such as chlorhexane, chlorocyclohexane, trichlorotrifluoroethane, methylene chloride, and carbon tetrachloride; nitriles such as acetonitrile and benzonitrile; sulfolane, methyl Sulfones such as sulfolane and dimethylsulfolane; tetrahydrofuran, 1.4
- Ethers such as dioxane and 1,2-dimethoxyethane; Ketones such as acetone and methyl ethyl ketone; Esters such as ethyl acetate and ethyl benzoate;
Examples include amides such as N-dimethylacetamide, N-methylpyrrolidone, and hexamethylphosphoramide. In the method of the present invention, other additives may be added to the reaction system as necessary in order to carry out the reaction more efficiently. Suitable examples of such additives include zeolites, salts of nitrogen-containing compounds and hydrogen halides, onium halides, and alkali metal salts and alkaline earth metal salts of hydrohalic acid. In the method of the present invention, the reaction is usually carried out at 80 to 300°C.
Preferably it is carried out at a temperature range of 120 to 220°C. The reaction pressure is 1 to 500Kg/cm ² , preferably 20 to 300Kg/cm 2 .
Kg/cm ² , and the reaction time varies depending on the reaction system, catalyst system, and other reaction conditions, but is usually from several minutes to several hours. Further, the reaction of the present invention can be carried out either batchwise or continuously in which the reaction solution is continuously drawn out while continuously supplying the reaction components. Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples. Example 1 A stirring autoclave with an internal volume of 140 ml was charged with N.
N'-diphenyl urea 20 mmol, ethanol 40 ml,
After adding 0.5mgatom of palladium black, 1mmol of iodine, and 1mmol of triethylamine and replacing the inside of the system with carbon monoxide, 80Kg/cm ² of carbon monoxide and then 6Kg/cm ² of oxygen were introduced to make the total pressure 86Kg/cm ² . . After reacting at 160°C for 1 hour with stirring, the reaction mixture was filtered and the filtrate was analyzed. As a result, the reaction rate of N・N'-diphenylurea was 98%, and the yield of ethyl N-phenylcarbamate was 98%. The selection rate was 96% and 98%. Note that no palladium was detected in the solution. Examples 2 to 26 Reactions were carried out in exactly the same manner as in Example 1, except that various basic substances (1 mmol) were used in place of triethylamine. Iodine (1 mmol) was used as the halogen. The results are shown in Table 1.

【table】

[Table] A 10% aqueous solution of tetrapropylammonium hydroxide was used. DBU is 1,8-diazabicyclo-
[5.4.0] represents undecene-7. Comparative Example 1 The same reaction as in Example 1 was carried out using only palladium black without using any iodine or basic substance. As a result, the reaction rate of N・N'-diphenylurea was 10
%, ethyl N-phenylcarbamate was produced in a yield of only 3%. Comparative Example 2 When the same reaction as in Example 1 was carried out using only 0.5 mmol of palladium chloride instead of the catalyst system consisting of palladium black, iodine and triethylamine, a dark brown opaque liquid containing dark brown suspended matter was obtained. It was done. Analysis of this reaction solution showed that the reaction rate of N・N'-diphenylurea was 63%, but the yield of ethyl N-phenylcarbamate was 43%, and the selectivity was only 68%. Ta. Next, the reaction mixture from which organic matter had been removed was put into the autoclave again, 20 mmol of N.N'-diphenylurea and 40 ml of ethanol were added, and the same method as above was repeated under pressure of carbon monoxide and oxygen. - The reaction rate of N'-diphenylurea was 61%, the yield of ethyl N-phenylcarbamate was 33%, and the selectivity was 54%. Example 27 1 mmol of bromine instead of iodine in Example 1
The reaction was carried out in the same manner as in Example 1 except that the reaction rate of N・N'-diphenylurea was 83
%, the yield of ethyl N-phenylcarbamate is
The selection rate was 93% with 77%. Example 28 The reaction was carried out in exactly the same manner as in Example 1, except that an ethanol solution of chlorine (containing about 1 mmol of chlorine) was used instead of iodine in Example 1.
The reaction rate of N・N'-diphenyl urea was 64% and N-
The yield of ethyl phenylcarbamate was 48% and the selectivity was 75%. Example 29 20 mmol of N・N'-dicyclohexyl urea, 50 ml of methanol, 0.5 mg of palladium black, 1 m of iodine
As a result of carrying out the same reaction as in Example 1 using 1 mmol of N·N·N'·N'-tetramethylethylenediamine, the reaction rate of N·N'-dicyclohexylurea was 97%, and the reaction rate of N-cyclohexylcarbamine was 97%. The yield of methyl acid was 94% and the selectivity was 97%. Example 30 20 mmol of N・N'-dibenzylurea, ethanol
40ml, palladium black 1mgatom, iodine, 1m
mol, 1,5-diazabicyclo-[4,3,0]-
As a result of carrying out the same reaction as in Example 1 using 1 mmol of nonene-5 (DBN), the reaction rate of N·N'-dibenzylurea was 95% and the yield of ethyl N-benzylcarbamate was 93%. The rate was 98%. Example 31 30 mmol of tetramethylurea, 50 ml of methanol,
As a result of carrying out the same reaction as in Example 1 using 0.5mgatom of palladium black, 1mmol of iodine, and 1mmol of potassium hydroxide, the reaction rate of tetramethylurea was 75
The yield of methyl N.N-dimethylcarbamate was 68% and the selectivity was 91%. Example 32 20 mmol of urea, 40 ml of ethanol, palladium black
The same reaction as in Example 1 was carried out using 0.5 mgatom, 1 mmol of iodine, and 1 mmol of triethylamine. As a result, the reaction rate of urea was 90%, the yield of ethyl carbamate was 83%, and the selectivity was 92%. Example 33 20 mmol of N・N'-di(n-butyl)urea, 40 ml of ethanol, 0.5 mg of rhodium black, 1 m of iodine
Example 1 using 1 mmol of potassium bicarbonate
As a result of a reaction similar to
The reaction rate of (butyl)urea was 73%, the yield of ethyl N-n-butylcarbamate was 66%, and the selectivity was 90%. Example 34 20 mmol of N・N'-diphenyl urea, ethanol
40ml, palladium black 0.5mg atom, iodine 2m
Example 1 using 1 mmol of potassium hydroxide
As a result of carrying out the same reaction as above, the reaction rate of N·N'-diphenylurea was 95%, the yield of ethyl N-phenylcarbamate was 91%, and the selectivity was 96%. Comparative Example 3 The same reaction as in Example 34 was carried out without using potassium hydroxide. As a result, the reaction rate of N・N'-diphenylurea was 48%, and the yield of ethyl N-phenylcarbamate was 48%. The rate was 31% and the selection rate was 65%. Example 35 1 m of bromine instead of iodine in Example 34
As a result of carrying out the same reaction as in Example 34 except using 1 mmol of rubidium hydroxide instead of potassium hydroxide, the reaction rate of N・N'-diphenylurea was 76%, and ethyl N-phenylcarbamate The yield was 68% and the selectivity was 90%. Comparative Example 4 The same reaction as in Example 35 was carried out without using rubidium hydroxide. As a result, the reaction rate of N・N'-diphenylurea was 42%, and the yield of ethyl N-phenylcarbamate was 42%. The rate was 24% and the selection rate was 57%. Example 36 A stirred autoclave with an internal volume of 200ml was charged with N.
N'-diphenyl urea 30 mmol, nitrobenzene 15
After adding 50 ml of methanol, 1 mmol of potassium tetrabromopalladate, 2 mmol of iodine, and 2 mmol of triethylamine, and replacing the inside of the system with carbon monoxide, carbon monoxide was introduced under pressure at 120 kg/cm ² . The reaction was carried out at 180° C. for 6 hours while stirring. As a result of analyzing the reaction solution, the reaction rates of N・N′-diphenylurea and nitrobenzene were 30% and 30%, respectively.
38%, methyl N-phenylcarbamate is 15m
mol was produced. Examples 37 to 44 The same reactions as in Example 1 were carried out, except that various platinum group metals or compounds containing platinum group elements were used in place of palladium black in Example 1. The results are shown in Table 2.

[Table] In these examples, 0.5 mgatom is used as the metal element for the platinum group metal or platinum group compound, and the % expression indicates the weight % of the supported catalyst component. Pd-Te/C is a product in which palladium chloride and tellurium dioxide are co-supported on activated carbon at a molar ratio of 10:3, and then subjected to hydrogen ring reduction at 350°C.

Claims (1)

[Scope of Claims] 1. A method for producing a urethane compound by reacting a urea compound with carbon monoxide and an organic hydroxyl compound in the presence of an oxidizing agent, comprising (a) a platinum group metal and a compound containing a platinum group element; (b) at least one halogen selected from chlorine, bromine and iodine; and (c) at least one selected from basic substances. A method for producing a urethane compound characterized by using a system. 2. The method according to claim 1, wherein the oxidizing agent is molecular oxygen, an organic nitro compound, or both. 3. The method according to claim 2, wherein the oxidizing agent is molecular oxygen. 4. Claims 1 to 3, wherein the platinum group metal and the compound containing the platinum group element are palladium, rhodium, palladium compounds, and rhodium compounds.
The method described in any of the paragraphs. 5. The method according to any one of claims 1 to 4, wherein the halogen is bromine or iodine. 6 Claim 5 in which the halogen is iodine
The method described in section. 7. The method according to any one of claims 1 to 6, wherein the urea compound is N·N'-diarylurea. 8. The method according to claim 7, wherein the N.N'-diarylurea is N.N'-diphenylurea.