KR20000004943A - Carbonylation method of acetylenic unsaturated compound - Google Patents

Abstract

PURPOSE: The invention relates to a carbonylation method of acetylenic unsaturated compound, in which acetylenic unsaturated compound contacts with CO and coreactant, under the carbonylation condition in the presence of a catalyst system based on mono dentate monophosphine or monophosphite. CONSTITUTION: In the invention, supplied materials including acetylenic unsaturated compound and relatively small amount of 1, 2-alkadiene compound, are based on a) 1 or more 8 class metal cation source; b) phosphine having aromatic substituent containing imino nitrogen atom separated from phosphorous by at least 1 bridging carbon atom; and c) protonic acid.

Description

Carbonylation Method of Acetylene Unsaturated Compound

EP-A-0, 271 and 144 disclose the synthesis of acetylenically unsaturated compounds in the presence of a palladium compound, an amphoteric asset, and a catalyst system that can be formed from organic monophosphines such as diphenyl-2-pyridylphosphine. Carbonylation is described.

Problems encountered in the carbonylation process of acetylenically unsaturated compounds include catalytic poisons by the isomeric 1,2-alkadiene compounds (so-called allen) typically found. Small amounts of allene, so-called up to 0.4%, are often acceptable, but the amounts commonly found in acetylene feedstocks pose a problem of the need to be addressed before they can be used in the carbonylation process.

EP-A-0, 441, 446 describe improved carbonylation catalyst systems that exhibit resistance (eg up to 7%) in basic conditions, i.e., in the presence of tertiary amines (vs. Example 12). See Comparative Example G). However, no information can be obtained from this document that even further improvements can be achieved with respect to the carbonylation process performed in the absence of tertiary amines.

Further improvement in allene resistance is described in WO 95/05357. According to this document, this process must be carried out in the presence of a (di) phosphine-based catalyst system containing an imino nitrogen atom and having aromatic substituents substituted in the specified manner with electron-primary groups.

The present invention relates to a method for carbonylating an acetylenically unsaturated compound, whereby a feedstock comprising an acetylenically unsaturated compound and a relatively small amount of 1,2-alkadiene compound is contacted with carbon monoxide and a co-reactant under carbonylation conditions. .

Surprisingly, Applicant has found that minimal allene resistance with minimal catalytic activity is achieved using synergistic combination of ligands. Thus, a process for carbonylating an acetylenically unsaturated compound is provided, whereby a feedstock comprising an acetylenically unsaturated compound and a relatively small amount of 1,2-alkadiene compound comprises: a) at least one Group 8 metal cation source of the periodic table; b) phosphines with aromatic substituents containing imino nitrogen atoms separated by at least one bridging carbon atom from a phosphorus atom, and c) based on an amphoteric, d) further monodentate monophosphine or monophosphite In the presence of a catalyst system characterized in that it is based on carbon monoxide and co-reactants are contacted under carbonylation conditions.

Due to the presence of the imino nitrogen atom, component b) is believed to act as a bidentate ligand which forms a chelate with the Group 8 metal cation. In particular, good results are observed when the imino nitrogen atoms are separated by a single carbon atom to form a 4-ring chelate. The role of component d) is unclear. This forms a complex with the Group 8 metal cation, but the catalyst thus prepared is poor in catalytic activity. However, the fact that no significant improvement is observed remains.

Components a), b) and c) are described extensively in the aforementioned patent documents. Preferably, the Group 8 metal is a platinum group metal (Ni, Pd or Pt), most preferably Pd. However, all Group 8 metals are known to provide Reppe catalysts which can be recognized or recognized for use in the carbonylation of acetylenes, which are therefore within the scope of the present invention. Group 8 metal cation sources are not critical. Typically, it is provided in the form of a metal salt, for example a metal salt of carboxylic acid, or a valent metal complex, or a metal complex in an oxidized state. Palladium acetate has proved to be particularly suitable as a preferred metal cation source.

Similarly, extensive description has been made of component b) of the catalyst system, which has at least one heterocyclic ring containing an imino nitrogen atom represented by -N = separated from a phosphorus atom by one bridging carbon atom. Mono- and diphosphine. This ring may have additional substituents. For example, component b) contains a heterocyclic group selected from pyridyl, pyrazinyl, quinolyl, isoquinolyl, pyrimidinyl, pyridazinyl, cinnolinyl, triazinyl, quinoxalinyl and quinalolinyl One mono- and diphosphine. The imino nitrogen atom is separated from the phosphorus atom by a single carbon atom, i.e. 2-pyridyl, 2-pyrazinyl, 2-quinolyl, 1-isoquinolyl, 3-isoquinolyl, 2-pyrimidinyl, Preferred are groups selected from 3-pyridazinyl, 3-cinnolinyl, 2-triazinyl, 2-quinoxalinyl and 2-quinalolinyl. Of these groups 2-pyridyl, 2-pyrimidyl and 2-triazinyl are particularly preferred.

Suitably, component b) is a monophosphine with one or two optionally substituted 2-pyridyl groups, with the remaining groups optionally substituted as described, for example, in EP-A-0, 386, 834 Selected from phenyl group and alkyl group.

In addition, the function of the positive asset (component c), which is the basis of the catalyst system, is believed to provide a positive resource. Positive assets can be generated on-site.

Preferably the protic asset has substantially noncoordinating anions, ie an anion that does not coordinate or only coordinate to a very small extent with the Group 8 metal. Preferred acids in this respect include acids with pKa (water at 18 ° C.) or less, for example so-called super acids; Sulfuric acid; Sulfonic acid; Halogenated carboxylic acid; Perhalonic acids such as perchloric acid, and acidic ion exchange resins such as sulfonated ion exchange resins. Hydrogen halides are preferably avoided because they tend to easily form metal complexes and corrode. Preferred examples of suitable amphoterics include optionally substituted alkylsulfonic acids such as arylsulfonic acids such as sulfonic acid, (trifluoro) methanesulfonic acid, tert-butanesulfonic acid, and toluenesulfonic acid.

In turn, component d) of the catalyst system may be aromatic phosphine or phosphite, aliphatic phosphine or phosphite, or mixed aromatic / aliphatic phosphine or phosphite. Preferred phosphines may be primary, secondary, or tertiary. Phosphite is suitably third grade. Suitable phosphines and phosphites include those of the general formulas PQ ₃ and P (OQ) ₃ , wherein each Q is independently an optionally substituted aryl group, an optionally substituted (cyclo) alkyl group, or two or three Q Together form a ring in which the phosphorus atoms are bridging groups. Preferably, aryl or alkyl groups have up to 20 carbon atoms, while cycloalkyl groups have 5 to 7 carbon atoms in the ring. Most preferably, component d) is phosphine, typical examples of which can be found in EP-A-0, 186, 228. Substituted triphenylphosphines may also be used in view of good properties, but preferably, triphenylphosphine, which is relatively inexpensive and readily available, is used.

Catalysts based on bidentate diphosphine and monodentate monophosphine for the carbonylation of (pure) acetylene are already known to be exemplified in EP-A-0, 186, 228. However, this document makes no suggestion regarding the improved allen resistance known to date.

The number of moles of components b) and d) and the number of moles of protons per mole of Group 8 metal atoms can vary considerably. The recommended amounts of components b) and d) range from 10 to 200 moles, in particular from 20 to 160, per mole of Group 8 metal atom, respectively. Suitably, the molar ratio of component d) to component b) ranges from 50: 1 to 1:50, more suitably 20: 1 to 1:20, subject to the concentration of allene in the feed. Thus, when a feed containing a relatively high amount of allene is used, a relatively high amount of component d) also applies. Preferred ratios are readily known since the catalytic activity is reduced when an optimal amount of component d) is used. The amount of protons is preferably selected in such a way that there are 2 to 500 moles of protons per mole of Group 8 metal atom.

The catalyst system of the present invention may be uniform or non-uniform, but is preferably uniform. The amount of catalyst applied is suitably selected in such a way that 10 ⁻⁸ to 10 ⁻¹ mole of Group 8 metal atoms, preferably 10 ⁻⁷ to 10 ^−2, are present on the same basis per mole of acetylenically unsaturated compound to be converted.

Acetylene-based unsaturated compounds suitable for use as starting materials in the process of the present invention include optionally substituted alkyne having 2 to 20 carbon atoms per molecule. Examples are acetylene, propyne, 1-butyne, 2-butyne, 1-hexine, phenyl acetylene and benzylethine. Preferably, unsaturated alkynes having 3 to 10 carbon atoms are used. Given commercial trade for carbonylated products, propyne is the preferred starting material.

As mentioned above, the main advantage of the catalyst system of the present invention lies in the resistance to 1,2-alkadiene compounds in the acetylene feedstock. Thus, commercial feedstocks containing small amounts of 1,2-alkadiene compounds, such as propadiene, and acetylenically unsaturated compounds can be used. Generally, 1,2-alkadienes in a content of at least 10% based on acetylenically unsaturated compounds may be acceptable. The use of a feedstock having a lower amount of 1,2-alkadiene compound, suitably in the range of 0.002 to 0.05 mole per mole of acetylenically unsaturated compound, is recommended.

The co-reactant may be a hydroxyl-containing compound such as monovalent, divalent or polyvalent alkanols, phenols, or water, but also the carboxylic acids described in J. Falbe's "New Syntheses with Carbon Monoxide (1980, p. 173)". , Mercaptans and amines. Particular preference is given to monovalent alkanols having 1 to 4 carbon atoms. Of these, methanol is most preferred.

Co-reactants are used in modest excess, eliminating the need for individual diluents or solvents. However, liquid diluents can be used if desired. Preferably, non-alkaline diluents, for example ketones such as methylisobutylketone, or ethers such as for example dipropylether or 2,5,8-trioxanonan (diglyme) are used.

Due to the high activity of the catalyst, the process of the invention proceeds easily at the appropriate reaction conditions. Suitably the reaction may be carried out at ambient temperature, for example about 20 ° C., but the reaction temperature is conveniently for this higher, for example in the range 20 to 200 ° C., suitably in the range 50 to 150 ° C. The reaction pressure is generally selected in the range of 1 to 100 bar. Pressures higher than 100 bar can be used but are generally not economically preferred due to the requirements of the particular device. Preferably, the pressure is in the range of 5 to 70 bar.

The invention is illustrated by the following, non-limiting examples.

All experiments are performed in 250 ml "Hastelloy C" (tradename) magnetically stirred autoclave. The autoclave is charged with 0.025 mmol of palladium (II) acetate, selected phosphines and methanesulfonic acid (MSA) or trifluoromethanesulfonic acid (TMSA) in the amounts indicated in the table below, and 50 ml of methanol.

Simultaneously withdraw the air from the autoclave, add 30 ml of propadiene-containing propene feed. Subsequently, carbon monoxide is supplied at a pressure below 60 bar. Seal the autoclave and heat to the desired reaction temperature.

At the same time the constant pressure is lowered (reaction completion time = reaction time), the contents of the autoclave are cooled and the samples are collected and analyzed by gas phase liquid chromatography. Conversion selectivity and average conversion (based on molar products / molar Pd / hour) of propadiene-containing propene feeds are listed in Table 1.

conclusion

As can be seen in Comparative Example A, the catalyst system based on monodentate monophosphine is not resistant to propadiene. Comparative Example B teaches that bidentate phosphine also lacks resistance. Comparative Example C is Example I (b) of WO 95/05357. As described in Comparative Example D, it performs much better at slightly higher temperatures, but the performance of these ligands is poor. This is unfortunate because the reaction will be exothermic and will require extensive cooling if high performance is maintained. Comparative Example E is also Comparative Example A (a) of WO 95/05357. Comparative Example F is, for example, Example 17 of EP-A-0, 441, 446 containing tertiary amines rather than monophosphine or monophosphite, using 30 ml methanol and 30 ml MMA as solvent Is performed.

Examples 1-3 illustrate that the combined presence of both components b) and d) substantially increases the reaction rate, even in the presence of a significant amount of propadiene. Examples 4-8 illustrate that the reaction rate can be further improved by substitution of component b) or d).

Example b) ^{@ (mmol)} d) ^# (mmol) c) (mmol) Allen (%) T (℃) Execution time (hr) Execution speed (mol / mol.hour) Selected MMA (%) A (Compare) B (Compare) C (Compare) D (Compare) E (Compare) F (Compare) 12345678 -PN (1) 6-Cl-PN (1) 6-Cl-PN (1) PN (1) 6-Me-PN (1) PN (1) PN (0.5) PN (0.25) PN (1) PN (1) 6-Cl-PN (1) 6-Bu-PN (1) 2,6-DPPN (0.25) PPh ₃ (4) ---- Dimethyl-p-toluidine (10) PPh ₃ (2) PPh ₃ (3.5) PPh ₃ (3.75) P (m-ClPh) ₃ (3) P (p-MeOPh) ₃ ( 3) PPh ₃ (3) PPh ₃ (3) PPh ₃ (3. 75) MSA (4) MSA (2) TMSA (2) TMSA (2) TMSA (2) MSA (2) MSA (2) MSA (4) MSA (4) MSA (4) MSA (4) MSA (4) MSA ( 4) MSA (4) 3.03.52.22.22.32.03.12.02.85.08.2 * 3.71.31.3 6070457050607060607080806060 5.05.00.51.55.05.00.50.51.00.250.250.51.00.5 <101.00024.0004.0006257.00030.00025.0007.00042.00040.00028.00018.00020.000 89.099.299.699.499.099.999.098.899.298.698.999.499.899.8 ＠ PN = diphenyl-2-pyridylphosphine; 6-Cl-PN = diphenyl (6-chloro-2-pyridyl) phosphine; 6-Me-PN = diphenyl (6-methyl-2-pyridyl) phosphine; 6-Bu-PN = diphenyl (6-butyl-2-pyridyl) phosphine; 2,6-DPPN = 2,6-bis (diphenylphosphino) pyridine # PPh ₃ = triphenylphosphine; P (m-ClPh) ₃ = tri (meth-chlorophenyl) phosphine; P (p-MeOPh) ₃ = tri (para-methoxyphenyl) phosphine. Dimethyl-p-toluidine is not component d) as defined herein. * 15 ml propyne / propadiene instead of 30 ml

Claims (10)

A feedstock comprising an acetylenically unsaturated compound and a relatively small amount of 1,2-alkadiene compound comprises a) at least one Group 8 metal cation source of the periodic table; b) phosphines with aromatic substituents containing imino nitrogen atoms separated by at least one bridging carbon atom from a phosphorus atom, and c) based on an amphoteric and further d) monodentate monophosphine or monophosphite A carbonylation process of an acetylenically unsaturated compound in contact with carbon monoxide and co-reactants under carbonylation conditions in the presence of a catalyst system characterized by The process of claim 1 wherein the catalyst system is based on monophosphine as component d). The process according to claim 1 or 2, wherein the catalyst system is based on triphenylphosphine optionally substituted with component d). 4. The process of any of claims 1 to 3, wherein the catalyst system is based on palladium as a Group 8 metal. The process according to claim 1, wherein the catalyst system is based on a mono- or diphosphine with aromatic substituents each containing an imino nitrogen atom separated by a single bridging carbon atom from the phosphorus atom. 6. The process of claim 5 wherein the catalyst system is based on 2-pyridylphosphine optionally substituted with component b). The process according to claim 1, wherein the catalyst system is based on components b) and d) present in a molar ratio of 50: 1 to 1:50. The method according to any one of claims 1 to 7, wherein the amount of the 1,2-alkadiene compound in the feedstock is 0.1 mol or less per mol of the acetylene-based unsaturated compound. 9. The process according to claim 8, wherein the molar amount of the 1,2-alkadiene compound in the feedstock per mole of acetylenically unsaturated compound ranges from 0.002 to 0.05. 10. The process according to any one of claims 1 to 9, wherein methyl methacrylate is prepared by reacting a feedstock comprising propene and 1,2-propadiene with carbon monoxide and methanol.