DE102010042214A1 - Catalyst system for the oxidative carbonylation of diols and polyols - Google Patents

Abstract

The invention relates to the use of a catalyst system containing at least one redox catalyst and at least one cocatalyst for the production of cyclic carbonates via reaction of diols or polyols with molecular oxygen and carbon monoxide.

Description

The present invention relates to a process for the preparation of cyclic carbonates via oxidative carbonylation of diols and polyols using a redox catalyst and a cocatalyst.

Cyclic carbonates are suitable for the preparation of diaryl carbonates via transesterification and are therefore industrially of great importance. Diaryl carbonates are starting materials for the preparation of polycarbonates by the melt transesterification process (see, for example, in US Pat Chemistry and Physics of Polycarbonates, Polymer Reviews, H. Schnell, Vol. 9, John Wiley and Sons, Inc., 1964 ), are precursors of active substances from the pharmaceutical and phytosanitary sector and are suitable for the production of phenylurethanes. It is known that diaryl carbonates can be obtained by interfacial phosgenation (Schotten-Baumann reaction) of aromatic hydroxy compounds. However, this process has considerable disadvantages, such as the use of phosgene and solvents, such as methylene chloride.

In addition, cyclic carbonates of diols and polyols can also be used as solvents. Glycerine carbonate and the glycidol ( EP 582 201 A2 ) are useful as intermediates for the preparation of polymers. For example, epoxy resins of glycidyl esters of polycarboxylic acids ( Hel. Chim. Acta, 60 (1977) 1845 ) or glycidyl methacrylate as a polymer crosslinker (Hel. Chim. Acta, 60 (1977) 1845).

The oxidative carbonylation of aliphatic diols is known from EP 463 678 A2 , In this case, cobalt (II) acetate is used as oxidant in quasi-stoichiometric amounts. The turnover number with respect to cobalt is 1.7. Disadvantages are the low catalyst activity and the low yield (2%).

The font J. Org. Chem. 51 (1986) 2977 describes the reaction of ethylene glycol and 1-phenylethanediol to the corresponding cyclic carbonates. Using stoichiometric amounts of PdCl ₂ and 2 equivalents of NaOAc, the carbonates are obtained in 91 and 73% yield, respectively. By adding stoichiometric amounts of 2 equivalents of CuCl ₂ as the oxidant, 1-phenylethanediol can also be converted to the corresponding cyclic carbonate using 0.1 equivalent of PdCl ₂ . The disadvantage is the use of metal salts in stoichiometric amounts.

The font Organometallics 25 (2006) 2872 describes the production of ethylene carbonate from ethylene glycol. The disadvantage is that here too the Pd catalyst is required in stoichiometric amounts.

The font Tetrahedron Letters 50 (2009) 7330 describes the use of palladium iodide for the oxidative carbonylation of 1,2-diols of the formula HO-CHR-CH ₂ -OH with R = H, Et, Ph and 1,3-diols of the formula HO-CHR-CH ₂ -CH ₂ -OH with R = H, Me and HO-CH ₂ -CHR-CH ₂ -OH at 100 ° C and 20 bar of a CO-oxygen mixture. After a reaction time of 15 hours, the cyclic carbonate was obtained in a yield of 42 to 94%. This corresponds, for a ratio of substrate to catalyst of 100 or 200, to a turnover number with respect to palladium between 66 to 188 and a turnover frequency between 2.8 and 12.5 moles of _diol mol _Pd ^-1 h ^-1 . Disadvantages are the short service life of the Pd catalyst and the low catalyst activity.

The patent EP 582 201 A2 describes the preparation of glycerol carbonate via reaction of glycerol with carbon monoxide and oxygen in the presence of copper (I) chloride. Disadvantages are the short service life and activity of the catalyst with a turnover number of 4.7 and a turnover frequency of 0.07 mol of _glycerol mol _Cu ^-1 h ^-1 without use of a solvent or with a turnover number of 9.6 and a turnover frequency of 0.5 mol of _glycerol mol _Cu ^-1 h ^-1 in nitrobenzene. Another disadvantage is the high reaction temperature of 110-130 ° C.

From the patent DE A 22 65 228 is a process for the preparation of polymeric glycolates from glycols with CO / O ₂ in the presence of catalysts of group Ib, IIb and VIII of the Periodic Table of the Elements known. The disadvantage is the formation of preferably oligomeric carbonates and the low selectivity (<33% by weight) to cyclic carbonates. From the patent DE A 22 22 488 For example, a process for the preparation of cyclic glycol carbonates from glycols with CO / O ₂ in the presence of copper ions is known. A disadvantage is the low activity of the catalyst with a turnover frequency below 30 mol of _glycol mol _Cu ^-1 h ^-1 .

The use of noble metals as a catalyst is known for the preparation of diaryl carbonates via oxidative direct carbonylation of aromatic hydroxy compounds in the presence of CO and O ₂ (see, for example, US Pat. DE-OS 27 38 437 . US-A 4,349,485 . US-A 5,231,210 . EP-A 667 336 . EP-A 858 991 . US Pat. No. 5,760,272 ). In the prior art such. B. J. Mol. Cat. A: Chem. 151 (2000) 37-45 For example, copper, manganese or cobalt salts are added in excess relative to the noble metal catalyst. However, this reaction system is basically not transferable to the oxidative carbonylation of aliphatic diols, since aliphatic diols have a different chemical reactivity than aromatic hydroxy compounds.

It was therefore an object to provide an improved catalyst system for the oxidative carbonylation of diols and polyols, which provides a higher catalyst stability and enables a faster reaction with increased selectivity.

Surprisingly, it has now been found that the palladium catalyst has a higher stability in the presence of a cocatalyst, higher turnover numbers (TON) are achieved and at least the same high catalyst activity (indicated as turnover frequency, TOF) is achieved at reduced reaction temperatures.

The invention therefore provides a catalyst system comprising at least one redox catalyst and at least one cocatalyst and its use for the preparation of cyclic carbonates via oxidative carbonylation of diols and polyols. The task of the cocatalyst is to accelerate the reoxidation of the redox catalyst with molecular oxygen. Another object of the invention are cyclic carbonates prepared by oxidative carbonylation of aliphatic diols and polyols using the inventive combination of redox catalyst and cocatalyst. The invention further provides a process for the preparation of diaryl carbonates and polycarbonates, starting from dialkyl carbonates and monophenols, which comprises recycling the alkylene glycol formed in the preparation of the dialkyl carbonate from cyclic alkylene carbonate and alkyl alcohol by reaction with carbon monoxide to give the alkylene carbonate, which is subsequently used again with the alkyl alcohol for the preparation of the dialkyl carbonate. The monophenol which is released in the preparation of solvent-free polycarbonate by transesterification of diaryl carbonates and bisphenols can in turn be used to prepare the diaryl carbonate.

wobei
R¹, R², R³ und R⁴ jeweils unabhängig voneinander H, lineares oder verzweigtes, gegebenenfalls substituiertes C₁-C₃₄-Alkyl, bevorzugt C₁-C₆-Alkyl, besonders bevorzugt C₁-C₄-Alkyl, C₅-C₃₄-Cycloalkyl, C₇-C₃₄-Alkylaryl, C₆-C₃₄-Aryl oder den Rest eines 5- oder 6-gliedrigen aromatischen Heterocyclus mit 1 oder 2 Heteroatomen aus der Gruppe von N, O und S bedeuten, wobei die isocyclischen und heterocyclischen Reste durch 1 oder 2 Substituenten wie ein geradkettiges oder verzweigtes C₁-C₄-Alkyl, geradkettiges oder verzweigtes C₁-C₄-Alkoxy, geradkettiges oder verzweigtes C₁-C₄-Alkoxycarbonyl, die mit Phenyl, Cyano und Halogen (z. B. F, Cl, Br) substituiert sein können und wobei weiterhin die heterocyclischen Reste mit einem ankondensierten Benzolkern verbunden sein können. R¹, R², R³, R⁴ kann jeweils unabhängig voneinander auch -COO-R⁵ bedeuten, wobei R⁵ H, gegebenenfalls verzweigtes C₁-C₃₄ Alkyl, bevorzugt C₁-C₆-Alkyl, besonders bevorzugt C₁-C₄-Alkyl, C₅-C₃₄-Cycloalkyl, C₇-C₃₄-Alkylaryl oder C₆-C₃₄-Aryl sein kann.Cyclic carbonates according to the process of the invention are compounds of the formula I,

in which
R ¹ , R ² , R ³ and R ^{4 are} each independently H, linear or branched, optionally substituted C ₁ -C ₃₄ -alkyl, preferably C ₁ -C ₆ -alkyl, more preferably C ₁ -C ₄ -alkyl, C ₅ -C ₃₄ -cycloalkyl, C ₇ -C ₃₄ -alkylaryl, C ₆ -C ₃₄ -aryl or the radical of a 5- or 6-membered aromatic heterocycle having 1 or 2 heteroatoms from the group of N, O and S, where the isocyclic and heterocyclic radicals are substituted by 1 or 2 substituents, such as a straight-chain or branched C ₁ -C ₄ -alkyl, straight-chain or branched C ₁ -C ₄ -alkoxy, straight-chain or branched C ₁ -C ₄ -alkoxycarbonyl which is bonded with phenyl, Cyano and halogen (e.g., F, Cl, Br), and further wherein the heterocyclic groups may be linked to a fused-on benzene nucleus. R ¹ , R ² , R ³ , R ⁴ may each independently also be -COO-R ⁵ , where R ^{5 is} H, optionally branched C ₁ -C ₃₄ -alkyl, preferably C ₁ -C ₆ -alkyl, more preferably C ₁ -C ₄ alkyl, C ₅ -C ₃₄ cycloalkyl, C ₇ -C ₃₄ alkylaryl or C ₆ -C ₃₄ aryl.

R ¹ and R ² , R ¹ and R ⁴ , or R ² and R ³ may each also together have a C ₂ -C ₂₀ alkylene chain, preferably - (CH ₂ -CH ₂ ) _n - with n = 2, 3, 4 or a heteroatom-substituted C ₂ -C ₂₀ alkylene chain, preferably -CH ₂ -O-CH ₂ -.

In the context of the invention, C ₁ -C ₄ -alkyl is, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, C ₁ -C ₆ -alkyl, moreover, for example for n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, neo-pentyl, 1-ethylpropyl, cyclohexyl, cyclopentyl, n-hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 1-methylpentyl, 2 Methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl , 2-ethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methylpropyl or 1-ethyl-2-methylpropyl, C ₁ -C ₃₄ -alkyl furthermore, for example, for n-heptyl and n-octyl, pinacyl, adamantyl, the isomeric menthyl, n-nonyl, n-decyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-hexadecyl or n-octadecyl. The same applies to the corresponding alkyl radical, for example in aralkyl or alkylaryl radicals. Alkylene radicals in the corresponding hydroxyalkyl or aralkyl or alkylaryl radicals are, for example, the alkylene radicals corresponding to the preceding alkyl radicals.

Aryl represents a carbocyclic aromatic radical having 6 to 34 skeleton carbon atoms. The same applies to the aromatic part of an arylalkyl radical, also called aralkyl radical, as well as aryl components of more complex groups, such as. B. arylcarbonyl radicals.

Arylalkyl or aralkyl in each case independently denotes a straight-chain, cyclic, branched or unbranched alkyl radical as defined above, which may be monosubstituted, polysubstituted or completely substituted by aryl radicals as defined above.

The preceding listings are exemplary and not limiting.

erhalten, wobei R¹, R², R³ und R⁴ die oben genannte Bedeutung haben.Cyclic carbonates of the formula I are prepared by reacting diols of the general formula II

wherein R ¹ , R ² , R ³ and R ^{4 have} the abovementioned meaning.

wobei R¹, R², R³ und R⁴ die oben genannte Bedeutung haben.Cyclic carbonates according to the process of the invention are also compounds of the formula III,

wherein R ¹ , R ² , R ³ and R ^{4 have} the abovementioned meaning.

erhalten, wobei R¹, R², R³ und R⁴ die oben genannte Bedeutung haben.Cyclic carbonates of the formula III are prepared by reacting diols of the general formula IV

wherein R ¹ , R ² , R ³ and R ^{4 have} the abovementioned meaning.

wobei R¹, R², R³ und R⁴ die oben genannte Bedeutung haben und
R⁶, R⁷ jeweils unabhängig voneinander und von den anderen Resten H, lineares oder verzweigtes, gegebenenfalls substituiertes C₁-C₃₄-Alkyl, bevorzugt C₁-C₆-Alkyl, besonders bevorzugt C₁-C₄-Alkyl, C₅-C₃₄-Cycloalkyl, C₇-C₃₄-Alkylaryl, C₆-C₃₄-Aryl, -COO-R⁵ oder den Rest eines 5- oder 6-gliedrigen aromatischen Heterocyclus mit 1 oder 2 Heteroatomen aus der Gruppe von N, O und S bedeuten, wobei die isocyclischen und heterocyclischen Reste durch 1 oder 2 Substituenten wie ein geradkettiges oder verzweigtes C₁-C₄-Alkyl, geradkettiges oder verzweigtes C₁-C₄-Alkoxy, geradkettiges oder verzweigtes C₁-C₄-Alkoxycarbonyl, die mit Phenyl, Cyano und Halogen (z. B. F, Cl, Br) substituiert sein können und wobei weiterhin die heterocyclischen Reste mit einem ankondensierten Benzolkern verbunden sein können.Cyclic carbonates according to the process of the invention are also compounds of general formula V, VI, VII or VIII

wherein R ¹ , R ² , R ³ and R ^{4 have} the abovementioned meaning and
R ⁶ , R ^{7 are} each independently of one another and the other radicals H, linear or branched, optionally substituted C ₁ -C ₃₄ -alkyl, preferably C ₁ -C ₆ -alkyl, more preferably C ₁ -C ₄ -alkyl, C ₅ -C ₃₄ -cycloalkyl, C ₇ -C ₃₄ -alkylaryl, C ₆ -C ₃₄ -aryl, -COO-R ⁵ or the radical of a 5- or 6-membered aromatic heterocycle having 1 or 2 heteroatoms from the group of N, O and S, wherein the isocyclic and heterocyclic radicals by 1 or 2 substituents such as a straight-chain or branched C ₁ -C ₄ -alkyl, straight-chain or branched C ₁ -C ₄ -alkoxy, straight-chain or branched C ₁ -C ₄ -alkoxycarbonyl which may be substituted with phenyl, cyano and halogen (e.g., F, Cl, Br), and further wherein the heterocyclic groups may be linked to a fused benzene nucleus.

erhalten, wobei R¹, R², R³, R⁴, R⁶ und R⁷ die oben genannte Bedeutung haben.Cyclic carbonates of the general formula V, VI, VII or VIII are obtained by reacting polyols of the general formulas IX, X, XI or X.

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁶ and R ^{7 have} the abovementioned meaning.

Examples of diols and polyols are: ethylene glycol, propylene glycol, phenylethylene glycol, glycerol, pentonic acid γ-lactones, erythrono-1,4-lactones, 3-methoxy-1,2-propanediol, 1,2-cyclohexanediol, 1,3-propanediol , Penta erythritol, di-trimethylolpropane.

The process according to the invention is preferably carried out as follows: the reaction mixture is heated to the desired reaction temperature and the reaction is started by introducing a carbon monoxide / oxygen gas mixture into the reaction solution. The steps can also be performed in reverse order.

The composition of the gas mixture can be chosen arbitrarily within wide limits. Instead of oxygen, an oxygen-containing gas mixture, such as air may be used, or the gas mixture may optionally be diluted with an inert gas such as nitrogen, argon or carbon dioxide. The ratio of carbon monoxide, oxygen and inert gas is preferably outside the explosive range. In general, a CO / O ₂ molar ratio of 100: 1 to 0.01: 1, preferably 50: 1 to 0.1: 1, more preferably 20: 1 to 0.5: 1, most preferably 8: 1 used up to 1: 1. When using inert gases, the partial pressure ratio of the active gases to inert gas is 98: 2 to 2:98, preferably 95: 5 to 20:80, particularly preferably 95: 5 to 50:50.

The reaction gases are introduced into the liquid in the reactor. For better mixing and dispersion of the reaction gases in the reactor, mechanical stirring may be effected in a preferred embodiment. Suitable reactor types are stirred tanks, stirred autoclave or bubble reactors or bubble columns, which can advantageously be heated and, if desired, may additionally be provided with a stirring device.

The process of the invention can be carried out in a wide pressure and temperature range. In general, the temperature may range from 0 to 200 ° C, preferably from 60 to 150 ° C, more preferably from 80 to 120 ° C. The reaction is expediently carried out under elevated pressure, generally at a pressure of 1 to 200 bar, preferably 5 to 100 bar, more preferably 10 to 30 bar.

The reaction is conveniently carried out in a preferred embodiment using the same diol, polyol or carbonate as the solvent. In an alternative embodiment or when using solid glycols, the glycol can be diluted with an inert solvent or dissolved in an inert solvent. Suitable inert solvents are aliphatic, aromatic or halogenated hydrocarbons, ethers, esters or carbonates. Preferred solvents are chlorobenzene, dichlorobenzene, toluene, xylene, DMF, dimethylacetamide, tetrahydrofuran, NMP, DME, ethyl acetate, ethylene carbonate or propylene carbonate.

The reaction can be carried out continuously or batchwise. In the preferred continuous mode of operation, the reaction gases are generally used in excess and the unreacted gas is circulated.

As the redox catalyst, at least one noble metal selected from palladium, rhodium, iridium and platinum in the elemental form or as their ionic or nonionic compounds is used. Preferably, the noble metal is used as a compound soluble in the reaction mixture. Particularly suitable, for example, the salts or the organometallic compounds of palladium in the oxidation state II, rhodium in the oxidation state I or III, iridium in the oxidation state I or III or platinum in the oxidation state II. The noble metals can, however, in another oxidation state and as Trägägers or unsupported finely dispersed metal can be used. Particular preference is given to using palladium as noble metal, it being possible for it to be present either as elemental or as compound. If salts are used, all anions are suitable as counterion, which are stable under reaction conditions and are only weakly coordinated to the metal ion. Examples of such salts are the sulfates, sulfonates, chlorides, bromides, acetates and trichloroacetates of the abovementioned noble metals. The redox catalyst is used in a weight ratio of substrate to catalyst compound of 50,000: 1 to 100: 1, preferably 10000: 1 to 1000: 1

The redox-active cocatalyst used is at least one compound selected from manganese, cobalt or copper compounds in a weight ratio of catalyst compound to redox-active substance of 1: 1 to 1: 100, preferably 1: 2 to 1:30. Examples of manganese, cobalt or copper compounds according to the process of the invention are their oxides, sulfates, halides, acetylacetonates or carboxylates.

In addition, a base, bromide sources, quaternary salts, various quinones or hydroquinones and drying agents can be used. Further, other redox-active substances, such as quinones, alkali or Erdalkaliiodide, in a weight ratio of catalyst compound to redoxaktiviver substance of 1: 1 to 1: 100, preferably 1: 2 to 1:30, be present. Examples of quinones are benzoquinone, naphthoquinone and anthraquinone, and their substitution products.

Further auxiliaries may be onium salts, such as ammonium, phosphonium or sulfonium salts, lead compounds, such as lead alkyls or oxides, polymers, such as polyvinylpyrrolidone, alkyl halides, such as dibromoethane, in a weight ratio of catalyst compound to auxiliaries of 1: 1 to 1: 10'000 , preferably 1:10 to 1: 1000, are used. Particular preference is given to using potassium bromide or the bromides of the ammonium or phosphonium compounds in a weight ratio of catalyst compound to auxiliaries of 1: 1 to 1: 10 000, preferably 1:10 to 1: 1000.

The process is suitable for an integrated process for the preparation of diaryl carbonates and polycarbonates (see 1 ). The alkylene glycol formed in the preparation of a dialkyl carbonate (eg dimethyl carbonate, DMC) from cyclic alkylene carbonate (eg ethylene carbonate, EGC - obtained, for example, by reaction of ethylene oxide (EO) with carbon dioxide) and alkyl alcohol (eg MeOH) (eg, ethylene glycol, EG) is recycled to the alkylene carbonate by reaction with carbon monoxide and oxygen. Subsequently, the alkylene carbonate is used to prepare the diaryl carbonate and the resulting alkyl alcohol is recycled. The monophenol which is released in the preparation of solvent-free oligo- or polycarbonate (PC) by transesterification of diaryl carbonates and bisphenols (eg bisphenol A, BPA) can in turn be used to prepare the diaryl carbonate.

The use of a cocatalyst for the reoxidation of the redox catalyst with molecular oxygen has not previously been described for the oxidative carbonylation of diols and polyols.

The cyclic carbonates prepared by the process according to the invention can be used as solvents or for the preparation of diaryl carbonates or polycarbonates or isocyanates.

1 shows an integrated process for the production of polycarbonate and recycling of the resulting ethylene glycol and the methanol and phenol.

The following examples serve to exemplify the invention and are not to be considered as limiting.

Examples

The following examples illustrate different embodiments for using the catalyst system of the invention for the oxidative carbonylation of diols.

example 1

Reaction of ethane-1,2-diol to ethylene carbonate

A 20 ml autoclave was charged with ethane-1,2-diol (55.86 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg; 0.0142 mmol), KBr (8.5 mg, 0.071 mmol) and DME (2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Ethylene carbonate was obtained in 20.3% yield. This corresponds to a TON in terms of palladium of 255 and a TOF with respect to palladium of 12.8 h ^-1 . Ethylene carbonate was the only detectable product.

Example 2

Reaction of ethane-1,2-diol to ethylene carbonate with reduced additive concentration and shorter reaction time

A 20 ml autoclave was charged with ethane-1,2-diol (55.86 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg, 0, 0142 mmol), KBr (0.085 mg, 0.71 μmol) and DME (2 ml). The autoclave was pressed with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 2 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Ethylene carbonate was obtained in 10.5% yield. This corresponds to a TON in terms of palladium of 133 and a TOF with respect to palladium of 66.5 h ^-1 . Ethylene carbonate was the only detectable product.

Example 3

Reaction of ethane-1,2-diol to ethylene carbonate using PdBr ₂ without the addition of an additive and reduced reaction time

A 20 ml autoclave was charged with ethane-1,2-diol (55.86 mg, 0.9 mmol), PdBr ₂ (0.19 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg, 0.0142 mmol), and DME (2 ml) charged. The autoclave was pressed with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 2 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Ethylene carbonate was obtained in 6.5% yield. This corresponds to a TON in terms of palladium of 98 and a TOF with respect to palladium of 49 h ^-1 . Ethylene carbonate was the only detectable product.

Example 4

Reaction of propane-1,2-diol to propylene carbonate

A 20 ml autoclave was charged with propane-1,2-diol (68.4 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg, 0, 0142 mmol), KBr (8.5 mg, 0.071 mmol) and DME (2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Propylene carbonate was obtained in 27.3% yield. This corresponds to a TON in terms of palladium of 342 and a TOF with respect to palladium of 17.1 h ^-1 . Propylene carbonate was the only detectable product.

Example 5

Reaction of propane-1,2-diol to propylene carbonate

A 20 ml autoclave was charged with propane-1,2-diol (68.4 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg; 0.0142 mmol), KBr (8.5 mg, 0.071 mmol) and ethyl acetate (2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Propylene carbonate was obtained in 47.5% yield. This corresponds to a TON in relation to palladium of 615 and a TOF with respect to palladium of 30.8 h ^-1 . Propylene carbonate was the only detectable product.

Example 6

Reaction of 1-phenylethane-1,2-diol to phenylethylene carbonate

A 20 ml autoclave was charged with 1-phenylethane-1,2-diol (124 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg, 0, 0142 mmol), KBr (8.5 mg, 0.071 mmol) and DME (2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Phenylethylene carbonate was obtained in 7.3% yield. This corresponds to a clay with respect to palladium of 91 and a TOF with respect to palladium of 4.5 h ^-1 . Phenylethylene carbonate was the only detectable product.

Comparative example to 6

Reaction of 1-phenylethane-1,2-diol to phenylethylene carbonate without using a cocatalyst

A 20 ml autoclave was charged with 1-phenylethane-1,2-diol (124 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), KBr (8.5 mg, 0.071 mmol) and DME ( 2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Phenylethylene carbonate was obtained in 0.5% yield. This corresponds to a TON in terms of palladium of 6 and a TOF with respect to palladium of 0.3 h ^-1 .

Without use of a cocatalyst, the yield is greatly reduced.

Example 7

Reaction of 1-phenylethane-1,2-diol to phenylethylene carbonate using CuCl ₂ as cocatalyst and sodium acetate as additive

A 20 ml autoclave was charged with 1-phenylethane-1,2-diol (124 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), CuCl ₂ (1.916 mg, 0.0142 mmol). , NaAc (73.827 mg, 0.9 mmol) and DME (2 mL). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Phenylethylene carbonate was obtained in 1.8% yield. This corresponds to a TON in terms of palladium of 24 and a TOF with respect to palladium of 1.2 h ^-1 . Phenylethylene carbonate was the only detectable product.

Comparative Example to 7

Reaction of 1-phenylethane-1,2-diol to phenylethylene carbonate without using a cocatalyst

A 20 ml autoclave was charged with 1-phenylethane-1,2-diol (124 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), NaAc (73.827 mg, 0.9 mmol) and DME ( 2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Phenylethylene carbonate was obtained in 0.4% yield. This corresponds to a TON with respect to palladium of 5 and a TOF with respect to palladium of 0.3 h ^-1 .

Without use of a cocatalyst, the yield is greatly reduced.

Example 8

Reaction of glycerine to glycerol carbonate

A 200 ml autoclave was charged with glycerol (491.8 mg, 5.34 mmol), PdAc ₂ (4.00 mg, 17.8 μmol), Mn (acac) ₃ (126.5 mg, 0.355 mmol), KBr ( 212.5 mg, 1.775 mmol) and acetone (100 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

Glycerol carbonate was obtained in 24.2% yield. This corresponds to a TON in relation to palladium of 75 and a TOF with respect to palladium of 3.8 h ^-1 . Glycerol carbonate was the only detectable product.

Example 9

Reaction of propane-1,3-diol to 1,3-dioxane-2-one

A 20 ml autoclave was charged with propane-1,3-diol (68.00 mg, 0.9 mmol), PdAc ₂ (0.16 mg, 0.71 μmol), Mn (acac) ₃ (5.06 mg, 0, 0142 mmol), KBr (8.5 mg, 0.071 mmol) and ethyl acetate (2 ml). The autoclave was pressurized with 20 bar of a nitrogen-oxygen-carbon monoxide mixture (91: 3: 6) and the reaction mixture heated to 60 ° C for 20 hours. After cooling, the reaction mixture was analyzed by gas chromatography.

1,3-dioxane-2-one was obtained in 10.0% yield. This corresponds to a TON in relation to palladium of 130 and a TOF in relation to palladium of 6.5 h ^-1 . 1,3-dioxane-2-one was the only detectable product.

QUOTES INCLUDE IN THE DESCRIPTION

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Cited patent literature

• EP 582201 A2 [0003, 0008]
• EP 463678 A2 [0004]
• DE 2265228A [0009]
• DE 2222488 A [0009]
• DE 2738437 A [0010]
• US 4349485 A [0010]
• US 5231210 A [0010]
• EP 667336A [0010]
• EP 858991A [0010]
• US Pat. No. 5,760,272 A [0010]

Cited non-patent literature

• Chemistry and Physics of Polycarbonates, Polymer Reviews, H. Schnell, Vol. 9, John Wiley and Sons, Inc., 1964 [0002]
• Hel. Chim. Acta, 60 (1977) 1845 [0003]
• J. Org. Chem. 51 (1986) 2977 [0005]
• Organometallics 25 (2006) 2872 [0006]
• Tetrahedron Letters 50 (2009) 7330 [0007]
• J. Mol. Cat. A: Chem. 151 (2000) 37-45 [0010]

Claims (14)

A process for the preparation of cyclic carbonates by catalytic oxidative carbonylation of diols or polyols in the presence of a gas mixture containing carbon monoxide and oxygen, characterized in that as catalyst at least one noble metal selected from palladium, rhodium, iridium and platinum in the elemental form or as their ionic or non-ionic compounds and, as cocatalyst, at least one compound selected from manganese, cobalt or copper compounds. A method according to claim 1, characterized in that the catalyst used are salts or organometallic compounds of palladium in the oxidation state II, rhodium in the oxidation state I or III, iridium in the oxidation state I or III or platinum in the oxidation state II and as. Process according to Claim 1 or 2, characterized in that the catalyst used is palladium in elemental form or as ionic or nonionic compound. A method according to any one of claims 1 to 3, characterized in that as redox-active cocatalyst at least one compound selected from manganese, cobalt or copper compounds, in a weight ratio of catalyst compound to redoxactive substance of 1: 1 to 1: 100, preferably 1: 2 to 1:30 is used. A method according to any one of claims 1 to 3, characterized in that further a base, bromide sources, quaternary salts, quinones, hydroquinones, alkali metal or Erdalkaliiodide or drying agents are used. Method according to one of claims 1 to 3, characterized in that further auxiliaries selected from onium salts, lead compounds, polymers, alkyl halides, bromide salts, in a weight ratio of catalyst compound to auxiliaries of 1: 1 to 1: 10'000 be added. A process according to any one of claims 1 to 6, characterized in that cyclic carbonates are compounds of the formula I,

R ¹ , R ² , R ³ and R ^{4 are} each independently H, linear or branched, optionally substituted C ₁ -C ₃₄ -alkyl, C ₅ -C ₃₄ -cycloalkyl, C ₇ -C ₃₄ -alkylaryl, C ₆ -C ₃₄ aryl or the radical of a 5- or 6-membered aromatic heterocycle having 1 or 2 heteroatoms from the group of N, O and S, wherein the isocyclic and heterocyclic radicals by 1 or 2 substituents such as a straight-chain or branched C ₁ -C ₄ -alkyl, straight-chain or branched C ₁ -C ₄ -alkoxy, straight-chain or branched C ₁ -C ₄ -alkoxycarbonyl which is substituted by phenyl, cyano and halogen (for example F, Cl, Br) and wherein furthermore the heterocyclic radicals can be connected to a fused-on benzene nucleus. R ¹ , R ² , R ³ , R ⁴ may each independently also be -COO-R ⁵ , where R ^{5 is} H, optionally branched C ₁ -C ₃₄ alkyl, C ₅ -C ₃₄ cycloalkyl, C ₇ -C ₃₄ Alkylaryl or C ₆ -C ₃₄ -aryl. A process according to any one of claims 1 to 7, characterized in that ethylene glycol, propylene glycol, phenylethylene glycol, glycerol, pentonic acid γ-lactones, erythrono-1,4-lactones, 3-methoxy-1,2-propanediol, 1, are used as the diol or polyol , 2-cyclohexanediol, 1,3-propanediol, pentaerythritol, di-trimethylolpropane. Method according to one of claims 1 to 8, characterized in that the catalyst is supported. A method according to any one of claims 1 to 9, characterized in that the CO / O ₂ molar ratio in the range of 20: 1 to 0.5: 1. A method according to any one of claims 1 to 10, characterized in that the method is operated at a temperature in the range of 60 to 150 ° C and under a pressure in the range of 5 to 100 bar. Method according to one of claims 1 to 11, characterized in that the method is operated continuously. Cyclic carbonate obtainable from the process according to one of claims 1 to 12. Use of a catalyst system containing as the catalyst at least one noble metal selected from palladium, rhodium, iridium and platinum in the elemental form or as their ionic or nonionic compounds and as cocatalyst at least one compound selected from manganese, cobalt or copper compounds for the preparation of cyclic carbonates via oxidative carbonylation of diols and polyols.

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