Phosphine ligands containing silicon hydride groups, methods for their preparation and use
By using a catalyst composed of phosphine ligands containing silane groups and transition metals, the problem of insufficient catalyst activity in existing olefin hydroformylation and hydroesterification reactions has been solved, achieving efficient and low-cost catalytic effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- EAST CHINA NORMAL UNIV
- Filing Date
- 2023-12-08
- Publication Date
- 2026-05-19
AI Technical Summary
Existing catalysts for olefin hydroformylation and hydrogen esterification reactions have insufficient activity and selectivity in industrial applications, and research on catalytic systems has not yet been widely industrialized.
Catalysts composed of phosphine ligands containing silane groups and transition metals are used for olefin hydroformylation or hydroesterification reactions. The preparation methods of the catalysts include the synthesis of monophosphine ligands and diphosphine ligands with silane groups, which are combined with transition metals such as cobalt, ruthenium, rhodium and palladium compounds to form a highly efficient catalytic system.
It improves the activity, selectivity and stability of olefin hydroformylation and hydrogen esterification reactions, and reduces the cost of generating aldehydes or carboxylic esters.
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Figure CN117683065B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of organic synthesis technology, and specifically to a phosphine ligand containing a silane group, its preparation method, and its application. Background Technology
[0002] Hydroformation of olefins refers to the process by which olefins react with syngas (H2 and CO) in the presence of a phosphine-ligand-modified transition metal catalyst to form an aldehyde with one more carbon atom. Hydroalkoxycarbonylation of olefins refers to the process by which olefins react with carbon monoxide (CO) and an alcohol (such as methanol) in the presence of a phosphine-ligand-modified transition metal catalyst to form a carboxylic acid (methyl) ester with one more carbon atom. The core of olefin hydroformation and hydroalkoxycarbonylation lies in the selection of the catalytic system. Research on catalytic systems for olefin hydroformation mainly focuses on transition metals such as Co, Rh, Ir, Pd, and Ru, but currently only Co and Rh are truly used in industrial-scale production. Research on catalytic systems for olefin hydroalkoxycarbonylation mainly focuses on the Pd transition metal, but it has not yet seen widespread industrial application. To date, catalysts for olefin hydroformylation have undergone four generations of evolution: unmodified Co2(CO)8 catalyst (generation 1), Co catalyst modified with tertiary phosphine ligands (generation 2), Rh catalyst system modified with PPh3 ligands, and rhodium catalyst modified with water-soluble phosphine ligand TPPTS (generation 3), and Rh catalyst modified with bisphosphite (generation 4) (US 4247486; US 4148830; CN 86106770; CN112010906 B; CN86106811; F. Ungvry, Coordin. Chem. Rev., 2005, 249, 2946-2961; R. Lazzaroni, Coordin. Chem. Rev., 2010, 254, 696-706; R. Franke, D. Selent, A. Boerner, Chem. Rev., 2012, 112, 5675-5732; PWNM van Leeuwen, inHomogeneous Catalysts: Understanding the Art, Kluwer 2004).
[0003] Studies have shown that the active catalysts for olefin hydroformylation and olefin hydroesterification are all carbonyl-coordinated metallic hydrogen species, such as HCo(CO)4 and HCo(CO) in olefin hydroformylation. x L 4-x HRh(CO) x L 4-xHPd(CO) in the hydrogen esterification reaction of olefins x L 3-x (L represents ligand). Therefore, effectively providing hydride anions to form active metallic hydrogen species is the key to obtaining highly active catalysts. Summary of the Invention
[0004] The purpose of this invention is to provide a phosphine ligand containing a silane group, wherein one or more of the phosphine ligand containing the silane group, together with a transition metal, forms a catalyst that efficiently catalyzes the hydroformylation or hydrogen esterification of olefins, and the catalyst exhibits excellent activity, selectivity and stability.
[0005] The present invention provides a phosphine ligand containing a silane group, the phosphine ligand containing a silane group includes a monophosphine ligand containing a silane group and a bisphosphine ligand containing a silane group, the monophosphine ligand containing a silane group has the structure shown in formula (I), and the bisphosphine ligand containing a silane group has the structure shown in formula (II).
[0006] ;
[0007] In formula (I), the silicon and phosphorus atoms in the silane group are located at the ortho, meta, or para positions of the benzene ring, and the R 1 The R is independently selected from any one of C1-C4 alkyl, C1-C4 alkoxy, or phenyl. 2 Independently selected from any one of C1-C4 alkyl or phenyl groups;
[0008] In formula (II), the silicon atom and the two phosphorus atoms in the silane group are simultaneously located at the ortho, meta, or para positions of the benzene ring, and the R 1 Independently selected from any one of C1-C4 alkyl, C1-C4 alkoxy, or phenyl, wherein R 2 It is independently selected from any one of C1-C4 alkyl or phenyl.
[0009] A method for preparing the above-mentioned phosphine ligand containing a silane group, wherein the preparation of the monophosphine ligand (I) containing a silane group includes the following steps:
[0010] (1) Using (o-, m-, or p-halophenyl)dialkyl (or diphenyl)phosphine as raw material, mix it with n-butyllithium in an equimolar ratio and react it at -78 °C for 0.5 to 2 hours to obtain (o-, m-, or p-phenyllithium)dialkyl (or phenyl)phosphine compound;
[0011] (2) The obtained (ortho-, meta-, or para-phenyllithium) dialkyl (or diphenyl)phosphine compound is mixed with diphenylchlorosilane or dialkylchlorosilane or dialkoxychlorosilane in equimolar amounts and reacted at -78 °C to room temperature for 1 to 4 hours to obtain a monophosphine ligand (Ia) containing a silane group.
[0012] ;
[0013] (3) Using [bis-(o-, meta- or para-halophenyl)]alkyl (or phenyl)phosphine as raw material, it is mixed with n-butyllithium at a molar ratio of 1:2 and reacted at -78 °C for 0.5 to 2 hours to obtain [bis-(o-, meta- or para-phenyllithium)]alkyl (or phenyl)phosphine compound;
[0014] (4) The obtained [bis-(ortho-, meta- or para-phenyllithium)]alkyl (or phenyl)phosphine compound is mixed with phenyl dichlorosilane or alkyl dichlorosilane or alkoxy dichlorosilane at a molar ratio of 1:2 and reacted at -78 °C to room temperature for 1 to 4 hours to obtain a monophosphine ligand (Ib) containing a silane group.
[0015] ;
[0016] The preparation of bisphosphine ligands (II) containing silane groups includes the following steps:
[0017] (1) Using (o-, m-, or p-halophenyl)dialkyl (or phenyl)phosphine as raw material, mix it with n-butyllithium in an equimolar ratio and react it at -78 °C for 0.5 to 2 hours to obtain (o-, m-, or p-phenyllithium)dialkyl (or phenyl)phosphine compound;
[0018] (2) The prepared (ortho-, meta-, or para-phenyllithium) dialkyl (or phenyl)phosphine is mixed with phenyl dichlorosilane or alkyl dichlorosilane or alkoxy dichlorosilane at a molar ratio of 2:1 and reacted at -78 °C to room temperature for 1 to 4 hours to obtain bisphosphine ligand (II) containing silane groups.
[0019] ;
[0020] A catalyst comprising a phosphine ligand and a transition metal, wherein the phosphine ligand is one or a combination of monophosphine ligands containing silane groups and bisphosphine ligands containing silane groups; and the transition metal comprises one of cobalt compounds, ruthenium compounds, rhodium compounds, iridium compounds, or palladium compounds.
[0021] The molar ratio of the phosphine ligand containing the silane group to the transition metal is 1 to 20:1.
[0022] One application of the catalyst is in an olefin hydroformylation reaction or an olefin hydrogen esterification reaction.
[0023] The olefins include one of the following: C3-C16 terminal olefins, C3-C16 internal olefins, and C4-C10 dienes.
[0024] The catalyst is applied to the hydroformylation reaction of olefins, specifically comprising: reacting the catalyst and the olefin in a high-pressure reactor at a temperature of 60-130 °C and a syngas pressure of 1.0-6.0 MPa for 2-20 hours to obtain an aldehyde with one more carbon atom than the olefin; the mass ratio of the transition metal to the olefin in the catalyst is 50-1300 ppm, and the volume ratio of carbon monoxide to hydrogen in the syngas is 1:1.
[0025] The catalyst is applied to the hydrogen esterification reaction of olefins, specifically comprising: reacting the catalyst, the olefin, and methanol in a high-pressure reactor at a temperature of 60-130 °C and a carbon monoxide pressure of 1.0-6.0 MPa for 6-24 hours to obtain a methyl carboxylate with one more carbon atom than the olefin; the mass ratio of the transition metal to the olefin in the catalyst is 50-1300 ppm, and the molar ratio of the olefin to methanol is 1:1-5.
[0026] The catalyst and the olefin hydroformylation or olefin hydrogen esterification reaction catalyzed by the catalyst described in this invention are carried out in a high-pressure reactor in an intermittent or continuous manner.
[0027] The phosphine ligands containing silane groups provided by this invention, in combination with transition metal catalysts, exhibit excellent activity, selectivity, and stability in the hydroformylation or hydrogen esterification of olefins. By using these phosphine ligands containing silane groups, the production cost of aldehydes prepared from olefins via hydroformylation or carboxylic esters prepared from olefins via hydrogen esterification can be greatly reduced. Detailed Implementation
[0028] The present invention will be described in more detail with reference to the following embodiments. However, these embodiments are merely illustrative and do not constitute any limitation on the invention. All reagents involved in the embodiments are commercially available products.
[0029] Examples 1-4: Synthesis of monophosphine ligands L1-L4 containing silane groups
[0030] ;
[0031] Example 1
[0032] Synthesis of L1: Under nitrogen protection, tetrahydrofuran (20 mL) was added to (2-bromophenyl)diphenylphosphine (4.5 mmol) and kept at -78°C for 30 minutes. Then, n-butyllithium (7.5 mmol) was added dropwise. After stirring at -78°C for 30 minutes, dimethylchlorosilane (5 mmol) was added dropwise. After stirring at -78°C for another 30 minutes, the reaction solution was gradually heated to room temperature. Distillation under reduced pressure yielded a white solid. Using n-hexane as eluent, rapid column chromatography yielded a white crystalline compound in 56% yield.
[0033] Example 2
[0034] Synthesis of L2: Under nitrogen protection, tetrahydrofuran (20 mL) was added to bis-(4-bromophenyl)phenylphosphine (5 mmol). After maintaining the temperature at -78°C for 30 minutes, n-butyllithium (12 mmol) was added dropwise. After stirring at -78°C for 30 minutes, methyldichlorosilane (5 mmol) was added dropwise. After continuing stirring at -78°C for another 30 minutes, the reaction mixture was gradually brought to room temperature. A white solid was obtained by vacuum distillation. A white crystalline compound was obtained by rapid column chromatography using n-hexane as eluent, with a yield of 43%.
[0035] Example 3
[0036] The synthesis method of L3 is the same as that of L1, except that the starting material dimethylchlorosilane is replaced with diisopropylchlorosilane. The structure is shown in structural formula L3.
[0037] Example 4
[0038] The synthesis method of L4 is the same as that of L1, except that the starting material dimethylchlorosilane is replaced with diphenylchlorosilane. The structure is shown in structural formula L4.
[0039] Example 5: Synthesis of L5, a bisphosphine ligand containing a silane group
[0040] ;
[0041] Synthesis of L5: Under nitrogen protection, tetrahydrofuran (20 mL) was added to (2-bromophenyl)diphenylphosphine (10 mmol), and the mixture was kept at -78°C for 30 minutes. Then, n-butyllithium (12 mmol) was added dropwise. After stirring at -78°C for 30 minutes, methyldichlorosilane (5.0 mmol) was added dropwise. After stirring at -78°C for another 30 minutes, the reaction was gradually brought back to room temperature. A white solid was obtained by vacuum distillation. A white crystalline compound was obtained by rapid column chromatography using a mixture of n-hexane and ethyl acetate as eluents, with a yield of 66%.
[0042] Examples 6-10
[0043] In a stainless steel high-pressure reactor lined with polytetrafluoroethylene, 30 mmol of 1-octene, 0.015 mmol of Rh(acac)(CO)2, and 0.12 mmol of L1 (L2, L3, L4, and / or L5) were added sequentially. Synthesis gas with a CO / H2 volume ratio of 1 was introduced to a pressure of 4.0 MPa. The reactor was sealed and reacted at 120 °C for 2 hours. After the reaction was complete, the reactor was cooled to room temperature, depressurized, and the organic phase was collected and analyzed by gas chromatography to determine the yield of nonanal. Table 1 shows the experimental results of the hydroformylation of 1-octene to nonanal catalyzed by a catalyst composed of phosphine ligands L1–L5 containing silane groups and Rh(acac)(CO)2.
[0044] Table 1. Catalytic results of the hydroformylation of 1-octene to nonanal using catalysts composed of phosphine ligands L1-L5 with different silane groups and Rh(acac)(CO)2. a
[0045]
[0046] a Rh(acac)(CO)2 0.05 mol%, phosphine ligand containing silane groups 0.4 mol%, 1-octene 30 mmol, CO / H2 (1:1) 4.0 MPa, 120℃, 2 hours.
[0047] b Gas chromatography analysis.
[0048] Examples 11-16
[0049] In a stainless steel high-pressure reactor lined with polytetrafluoroethylene, 30 mmol of 1-hexene, 10 mL of methanol, 0.3 mmol of Pd(OAc)₂, and 0.6 mmol of L1 (L2, L3, L4, and / or L5) were added sequentially. CO was introduced to 3.0 MPa, and the reactor was sealed and reacted at 100 °C for 8 hours. After the reaction, the reactor was cooled to room temperature, the pressure was released, and the reaction solution was analyzed by gas chromatography to determine the yield of methyl heptanoate. Table 1 shows the experimental results of the hydrogen esterification of 1-hexene to prepare methyl heptanoate catalyzed by a catalyst composed of phosphine ligands L1-L4 containing silanol groups and Pd(OAc)₂.
[0050] Table 2. Catalytic results of the hydrogen esterification of 1-hexene to prepare methyl heptanoate by catalysts composed of different phosphine ligands L1-L5 with silane groups and Pd(OAc)2. a
[0051]
[0052] aPd(OAc)2 1 mol%, phosphine ligand containing silane groups 2.0 mol%, 1-hexene 30 mmol, MeOH 10 mL, CO 4.0 MPa, 100℃, 8 hours.
[0053] b Gas chromatography analysis.
[0054] Examples 17-24
[0055] Table 3 presents the catalytic results of the hydroformylation of different olefins using catalysts composed of L3 and Rh(acac)(CO)2. In a stainless steel high-pressure reactor lined with polytetrafluoroethylene, 30 mmol of olefin, 0.015 mmol of Rh(acac)(CO)2, and 0.12 mmol of L3 were added sequentially. Synthesis gas with a CO / H2 volume ratio of 1 was introduced to a pressure of 4.0 MPa, and the reactor was sealed and reacted at 120 °C for 2 hours. After the reaction was completed, the reactor was cooled to room temperature, depressurized, and the reaction solution was analyzed by gas chromatography to determine the yield of the aldehyde product.
[0056] Table 3. Catalytic results of the hydroformylation of different olefins using catalysts composed of ligands L3 and Rh(acac)(CO)2. a
[0057]
[0058] a Rh(acac)(CO)2 0.05 mol%, L3 0.4 mol%, olefin 30 mmol, CO / H2 (1:1) 4.0 MPa, 120℃, 2 hours.
[0059] b Gas chromatography analysis.
[0060] Examples 25-32
[0061] Table 4 presents the catalytic results of the hydrogen esterification reactions of different olefins using catalysts composed of L1 and Pd(OAc)2. In a stainless steel high-pressure reactor lined with polytetrafluoroethylene, 30 mmol of olefin, 10 mL of methanol, 0.3 mmol of Pd(OAc)2, and 0.6 mmol of L1 were added sequentially. CO was introduced to 3.0 MPa, and the reactor was sealed and reacted at 100 °C for 8 hours. After the reaction was completed, the reactor was cooled to room temperature, depressurized, and the reaction solution was analyzed by gas chromatography to determine the yield of the carboxylic acid esters.
[0062] Table 4. Catalytic results of the hydrogen esterification reactions of different olefins using catalysts composed of ligands L1 and Pd(OAc)2. a
[0063]
[0064] a Pd(OAc)2 1 mol%, L1 2.0 mol%, olefin 30 mmol, MeOH 10 mL, CO 4.0 MPa, 100℃, 8 hours.
[0065] b Gas chromatography analysis.
[0066] Examples 33-37
[0067] Table 5 shows the recycling results of the catalyst composed of L3 and Rh(acac)(CO)2 in the 1-octene hydroformylation reaction. The catalyst maintained certain activity and stability after 5 cycles. In a stainless steel high-pressure reactor with a polytetrafluoroethylene liner, 30 mmol of 1-octene, 0.02 mmol of Rh(acac)(CO)2, and 0.12 mmol of L3 were added sequentially. Syngas with a CO / H2 volume ratio of 1 was introduced to 4.0 MPa, and the reaction was carried out at 120 °C for 2 hours. After the reaction, the mixture was cooled to room temperature, depressurized, and the reaction solution was analyzed by gas chromatography to determine the yield of the aldehyde product. Then, without separation, 30 mmol of 1-octene was added again, and syngas with a CO / H2 volume ratio of 1 was introduced to 4.0 MPa. The reaction was carried out at 120 °C for 2 hours, and the catalyst was recycled a total of 5 times.
[0068] Table 5 Results of recycling of the catalyst composed of L3 and Rh(acac)(CO)2 in the 1-octene hydroformylation reaction. a
[0069]
[0070] a Rh(acac)(CO)2 0.05 mol%, L3 0.4 mol%, 1-octene 30 mmol (added each time), CO / H2 (1:1) 4.0 MPa, 120℃, 2 hours.
[0071] b Gas chromatography analysis.
[0072] Examples 38-42
[0073] Table 6 shows the recycling results of the catalyst composed of L1 and Pd(OAc)2 in the 1-octene hydroesterification reaction. In a stainless steel autoclave with a PTFE liner, 30 mmol of 1-octene, 10 mL of methanol, 0.3 mmol of Pd(OAc)2, and 0.6 mmol of L1 were added sequentially. CO was introduced to 3.0 MPa, and the autoclave was sealed and reacted at 100 °C for 8 hours. After the reaction, the autoclave was cooled to room temperature, depressurized, and the reaction solution was analyzed by gas chromatography to determine the yield of methyl nonanoate. Then, without separation, 30 mmol of 1-octene and 5 mL of methanol were added, and CO was introduced to 4.0 MPa. The reaction was then carried out at 100 °C for 8 hours. This catalyst recycling process was repeated a total of 5 times.
[0074] Table 6. Results of recycling of the catalyst composed of L1 and Pd(OAc)2 in the 1-hexene hydrogen esterification reaction. a
[0075]
[0076] a Pd(OAc)2 1 mol%, L1 2.0 mol%, 1-hexene 30 mmol (added each time), initial MeOH 10 mL (5 mL added in cycles), CO 4.0 MPa, 100℃, 8 hours.
[0077] b Gas chromatography analysis.
Claims
1. The application of a phosphine ligand catalyst containing a silane group, characterized in that, The catalyst is applied to the hydroformylation reaction or the hydroesterification reaction of olefins; wherein the phosphine ligand containing silane groups includes monophosphine ligands containing silane groups and bisphosphine ligands containing silane groups, the monophosphine ligands containing silane groups have the structure shown in formula (I), and the bisphosphine ligands containing silane groups have the structure shown in formula (II). ； In formula (I), the silicon and phosphorus atoms in the silane group are located at the ortho, meta, or para positions of the benzene ring, and the R 1 Independently selected from any one of C1-C4 alkyl, C1-C4 alkoxy, or phenyl, wherein R 2 Independently selected from any one of C1-C4 alkyl or phenyl groups; In formula (II), the silicon atom and the two phosphorus atoms in the silane group are simultaneously located at the ortho, meta, or para positions of the benzene ring, and the R 1 Independently selected from any one of C1-C4 alkyl, C1-C4 alkoxy, or phenyl, wherein R 2 Independently selected from any one of C1-C4 alkyl or phenyl groups; The method for preparing the phosphine ligand containing a silane group, specifically the preparation of the monophosphine ligand (I) containing a silane group, includes the following steps: (1) Using (o-, m-, or p-halophenyl)dialkyl or diphenylphosphine as raw materials, mix them with n-butyllithium in an equimolar ratio and react them at -78 °C for 0.5 to 2 hours to obtain (o-, m-, or p-phenyllithium)dialkyl or diphenylphosphine compounds. (2) The obtained (ortho-, meta-, or para-phenyllithium) dialkyl or diphenylphosphine compound is mixed with diphenylchlorosilane or dialkylchlorosilane or dialkoxychlorosilane in equal molar amounts and reacted at -78 °C to room temperature for 1 to 4 hours to obtain a monophosphine ligand (Ia) containing a silane group. ； (3) Using [bis-(ortho-, meta- or para-halophenyl)]alkyl or phenylphosphine as raw material, mix it with n-butyllithium at a molar ratio of 1:2 and react it at -78 °C for 0.5 to 2 hours to obtain [bis-(ortho-, meta- or para-phenyllithium)]alkyl or phenylphosphine compound; (4) The obtained [bis-(ortho-, meta- or para-phenyllithium)]alkyl or phenylphosphine compound is mixed with phenyl dichlorosilane or alkyl dichlorosilane or alkoxy dichlorosilane at a molar ratio of 1:2 and reacted at -78 °C to room temperature for 1 to 4 hours to obtain a monophosphine ligand (Ib) containing a silane group. ； The preparation of bisphosphine ligands (II) containing silane groups includes the following steps: (1) Using (ortho-, meta-, or para-halophenyl)dialkyl or phenylphosphine as raw materials, mix them with n-butyllithium in an equimolar ratio and react them at -78 °C for 0.5 to 2 hours to obtain (ortho-, meta-, or para-phenyllithium)dialkyl or phenylphosphine compounds. (2) The prepared (ortho-, meta-, or para-phenyllithium) dialkyl or phenylphosphine is mixed with phenyl dichlorosilane or alkyl dichlorosilane or alkoxy dichlorosilane at a molar ratio of 2:1 and reacted at -78 °C to room temperature for 1 to 4 hours to obtain bisphosphine ligand (II) containing silane groups. ； The R 1 Independently selected from any one of C1-C4 alkyl, C1-C4 alkoxy, or phenyl, wherein R 2 Independently selected from any one of C1-C4 alkyl or phenyl groups; The catalyst is composed of a phosphine ligand and a transition metal, wherein the phosphine ligand is one or a combination of two of the aforementioned monophosphine ligands containing silane groups and bisphosphine ligands containing silane groups; and the transition metal is one of a rhodium compound and a palladium compound. The molar ratio of the phosphine ligand containing the silane group to the transition metal is 1 to 20:
1.
2. The application according to claim 1, characterized in that, The olefin is one of C3-C16 terminal olefins, C3-C16 internal olefins, and C4-C10 dienes.
3. The application according to claim 1, characterized in that, The catalyst is applied to the hydroformylation reaction of olefins, specifically comprising: reacting the catalyst and the olefin in a high-pressure reactor at a temperature of 60-130 °C and a syngas pressure of 1.0-6.0 MPa for 2-20 hours to obtain an aldehyde with one more carbon atom than the olefin; the mass ratio of the transition metal to the olefin in the catalyst is 50-1300 ppm, and the volume ratio of carbon monoxide to hydrogen in the syngas is 1:
1.
4. The application according to claim 1, characterized in that, The catalyst is applied to the hydrogen esterification reaction of olefins, specifically comprising: reacting the catalyst, the olefin, and methanol in a high-pressure reactor at a temperature of 60-130 °C and a carbon monoxide pressure of 1.0-6.0 MPa for 6-24 hours to obtain a methyl carboxylate with one more carbon atom than the olefin; the mass ratio of the transition metal to the olefin in the catalyst is 50-1300 ppm, and the molar ratio of the olefin to methanol is 1:1-5.