Bisphosphite ligands based on benzofenchol

Abstract

Disclosed are bisphosphite ligands based on benzopinacol, and their use for hydroformylation.

Description

Technical Field

[0001] This invention relates to benzenepinalol-based bisphosphite ligands and their use in hydroformylation. Background Technology

[0002] WO 2008 / 071508 A1 describes a method for hydroformylation using bisphosphite ligands. The use of ligand (D-1) is described in particular.

[0003] Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a new compound that provides an improved yield in the hydroformylation of olefins compared with compounds known from the prior art.

[0005] This problem is solved by the compound according to the present invention.

[0006] Compounds of formula (I):

[0007]

[0008] in

[0009] R 1 R 2 R 3 R 4 R 5 R 6 R 7 R 8 Each is selected independently from: -H, -(C1-C 12 -alkyl, -O-(C1-C 12 )-alkyl.

[0010] The expression "(C1-C 12 "-alkyl" and "-O-(C1-C" 12 "-alkyl" includes straight-chain and branched alkyl groups having 1 to 12 carbon atoms. These are preferably -(C1-C8)-alkyl groups or -O-(C1-C8)-alkyl groups, and particularly preferably -(C1-C4)-alkyl groups or -O-(C1-C4)-alkyl groups.

[0011] In one implementation, R 5 and R 8 Yes - (C1-C 12 )-alkyl.

[0012] In one implementation, R 5 and R 8 It is - tert-butyl.

[0013] In one implementation, R 6 R 7 Selected from: -(C1-C 12 -alkyl, -O-(C1-C 12 )-alkyl.

[0014] In one implementation, R 6 and R 7 It is -OCH3 or -tert-butyl.

[0015] In one implementation, R 1 R 2 R 3 R 4 Selected from -H, -(C1-C 12 )-alkyl.

[0016] In one implementation, R 1 R 2 R 3 R 4 It is -H or -tert-butyl.

[0017] In one embodiment, the compound has one of structures (1) to (6):

[0018]

[0019] In addition to the compound itself, protection is also claimed for methods of using the compound.

[0020] This method includes the following steps:

[0021] a) Initial feeding of an olefinic unsaturated compound;

[0022] b) Add the compounds described above and substances containing Rh;

[0023] c) Input H2 and CO,

[0024] d) Heating the reaction mixture obtained from a) to c) wherein the olefinic unsaturated compound is converted into an aldehyde.

[0025] In this method, steps a), b), and c) can be performed in any desired order. However, typically, the addition of CO is performed after the co-reactants have been initially added in steps a) and b). Alternatively, CO can be introduced in two or more steps, such that, for example, a portion of the CO is first introduced, the mixture is then heated, and another portion of the CO is subsequently introduced.

[0026] The olefinic unsaturated compounds used as reactants in the method according to the invention contain one or more carbon-carbon double bonds. For simplicity, these compounds are also referred to olefins below. The double bonds may be terminal or internal.

[0027] In a variation of the method, the olefinic unsaturated compound does not contain any functional groups other than carbon-carbon double bonds.

[0028] In a variant of the method, the olefinic unsaturated compound is selected from: ethylene, propylene, 1-butene, cis- and / or trans-2-butene, isobutene, 1,3-butadiene, 1-pentene, cis- and / or trans-2-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, hexene, tetramethylethylene, heptene, 1-octene, 2-octene, di-n-butene, or mixtures thereof.

[0029] In a variant of the method, the Rh-containing substance is selected from: Rh(acac)(CO)2, [(acac)Rh(COD)] (Umicore, acac = acetylacetonate anion; COD = 1,5-cyclooctadiene), Rh4CO 12 .

[0030] In a variation of the method, CO is introduced in step c) at a pressure ranging from 1 to 6 MPa (10 to 60 bar).

[0031] In a variation of the method, the reaction mixture is heated to a temperature in the range of 80°C to 160°C in step d). Detailed Implementation

[0032] The invention will be described in more detail below with reference to embodiments.

[0033] 2-((3,3'-di-tert-butyl-5,5'-dimethoxy-2'-((4,4,5,5-tetraphenyl-1,3,2-dioxaphosphazene) Cyclopentanyl-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphacyclopentadiene Synthesis of (dioxaphosphol)(1):

[0034]

[0035] A mixture of catechol (0.0824 g; 0.7483 mmol) and triethylamine (0.42 ml) in 3 ml of toluene was added dropwise to a solution of 2-((3,3'-di-tert-butyl-2'-((phosphaneyl))oxy)-5,5'-dimethoxy-[1,1'-biphenyl]-2-yl)oxy)-4,4,5,5-tetraphenyl-1,3,2-dioxaphosphacyclopentane (0.639 g; 0.7483 mmol) in 6 ml of toluene. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under vacuum. The obtained solid was dried at 60 °C / 0.1 mbar for 2 h and absorbed in 6.5 ml of hot acetonitrile. The solid formed after cooling was filtered off, washed with slightly cooled acetonitrile, and dried under vacuum. Yield: 0.426 g (0.5537 mmol, 74%).

[0036] Elemental analysis (C 54 H 52 Calculated value of O8P2 = 890.945 g / mol: C = 72.79 (72.80); H = 5.93 (5.88); P = 6.98 (6.95).

[0037] ESI-TOF HRMS: m / z=891.3212; [M + +H], calculated value m / z = 891.3215.

[0038] 31 P NMR (CD2Cl2): d 136.0 (d, J PP =55Hz); 146.9 (d,J) PP =55Hz).

[0039] 1 H NMR (CD2Cl2): d 1.29(s,9H); 1.35(s,9H); 3.74(s,3H); 3.80(s,3H); 6.75(m,1H); 6.82(m,1H); 6.95-7.16(m,22H); 7.32(m,4H)ppm.

[0040] 5-(tert-butyl)-2-((3,3'-di-tert-butyl-5,5'-dimethoxy-2'-((4,4,5,5-tetraphenyl-1,3,2- Dioxaphosphane-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphane Synthesis of pentadiene (2):

[0041]

[0042] A mixture of 4-tert-butylcatechol (0.0853 g; 0.5135 mmol) and triethylamine (0.29 ml) in 2 ml of toluene was added dropwise to a solution of 2-((3,3'-di-tert-butyl-2'-((dichlorophosphoalkyl)oxy)-5,5'-dimethoxy-[1,1'-biphenyl]-2-yl)oxy)-4,4,5,5-tetraphenyl-1,3,2-dioxaphosphacyclopentane (0.4384 g; 0.5135 mmol) in 4 ml of toluene. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under vacuum. The obtained solid was dried at 60 °C / 0.1 mbar for 2 h and absorbed in 4.3 ml of hot acetonitrile. The solid formed after cooling was filtered off, washed with slightly cooled acetonitrile, and dried under vacuum. Yield: 0.201 g (0.261 mmol, 51%).

[0043] Elemental analysis (C 58 H 60 Calculated value of O8P2 = 947.052 g / mol: C = 73.51 (73.56); H = 6.63 (6.39); P = 6.81 (6.54).

[0044] ESI-TOF HRMS: m / z=696.3655; [M + +Na], calculated value m / z = 696.3660.

[0045] 31 P NMR (CD₂Cl₂): d 135.7 (d, J) PP =44Hz); 136.0 (d,J) PP =55Hz); 145.0(d,J) PP =55Hz); 145.1(d,J) PP =44Hz)ppm.

[0046] 1 H NMR(CD2Cl2):d 1.29+1.31(2s,9H);1.33+1.34(2s,9H);1.35(s;4.5H);1.38(s,4.5H);3.73(s,1.5H);3.74(s,1.5H) ;3.77(s,1.5H);3.80(s,1.5H);6.73(m,1H);6.82(m,1H);6.90-7.13(m,21H);7.27-7.37(m,4H)ppm.

[0047] 4,6-Di-tert-butyl-2-((3,3'-Di-tert-butyl-5,5'-dimethoxy-2'-((4,4,5,5-tetraphenyl-1,3, 2-Dioxaphosphazenecyclopentane-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphazene Synthesis of cyclopentadiene (3):

[0048]

[0049] A solution of n-butyllithium was added dropwise to a solution of 3 in 4 ml of THF at -20°C. The mixture was stirred for another 20 minutes, then allowed to warm to room temperature, and Benzopinakol-Phosphorchloridit dissolved in 1.8 ml of THF was added dropwise. The reaction mixture was stirred overnight. Triethylamine A was then added, followed by a solution of phosphorus trichloride in 1.5 ml of THF, which was then added dropwise to the reaction mixture cooled to 0°C. The mixture was allowed to warm to room temperature and stirred for 6 hours.

[0050] Volatile components were removed from the mixed batch under vacuum, and the residue was dried at 60 °C and 0.1–0.5 mbar for 2 hours. The obtained solid was absorbed in 8 ml of toluene. A mixture of 3,5-di-tert-butylcatechol, triethylamine B, and 3 ml of toluene was added dropwise to the resulting suspension at room temperature. The mixture was stirred overnight, filtered (G4), the solvent was removed under vacuum, and the solid was dried at 60 °C and 0.1–0.5 mbar. Crude yield: 1.03 g (95%).

[0051] The crude product was dissolved in 11 ml of boiling acetonitrile. The mixture was first slowly cooled to room temperature and then stored overnight at -30°C. The precipitated solid was separated by siphoning off the supernatant mother liquor using an impregnated sintered sand core funnel (Tauchfritte) at -30°C and then vacuum dried at 60°C for 5 hours. Yield: 0.786 g (72%).

[0052] Elemental analysis (C 62 H 68 Calculated value of O8P2 = 1003.16 g / mol): C = 74.24 (74.23); H = 6.85 (6.83); P = 6.07 (6.18).

[0053] ESI-TOF HRMS: m / z=1025.4309; [M + +H], calculated value m / z = 1025.4287.

[0054] 31 P NMR(CD2Cl2):d 134.1(s,br); 134.5(d,J PP =77.3Hz); 144.6 (d,J) PP =77.3Hz); 145.2 (d,J) PP =24.7Hz), a mixture of two diastereomers.

[0055] 1H NMR(CD2Cl2):d 1.22(s); 1.27(s); 1.33(s); 1.34(s); 1.36(s); 1.44(s); 1.46(s); 1.47(s)ppm; S=36H.3.68(s); 3.69(s); 3.77(s); 3.87(s)ppm; S=12H.6.59-7.43ppm(m,26H).

[0056] 2-((3,3',5,5'-tetratert-butyl-2'-((4,4,5,5-tetraphenyl-1,3,2-dioxaphosphacyclopentane-2- Synthesis of benzo[d][1,3,2]dioxacyclopentadiene (4):

[0057]

[0058] A mixture of catechol (0.0964 g; 0.8760 mmol) and triethylamine (0.49 ml) in 3 ml of toluene was added dropwise to a solution of 4,4,5,5-tetraphenyl-2-((3,3',5,5'-tetratert-butyl-2'-((dichlorophosphonyl)oxy)-[1,1'-biphenyl]-2-yl)oxy)-1,3,2-dioxaphosphacyclopentane (0.7936 g; 0.8760 mmol) in 5 ml of toluene. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under vacuum. The obtained solid was dried at 60 °C / 0.1 mbar for 2 h and then stirred in 7 ml of acetonitrile for 1 h. The remaining solid was filtered off, washed with slightly cooled acetonitrile, and dried under vacuum. Yield: 0.6197 g (0.657 mmol, 75%).

[0059] Elemental analysis (C 60 H 64 Calculated values ​​of O6P2: 943.1076 g / mol; C: 76.48 (76.41); H: 6.84 (6.84); P: 6.57 (6.57).

[0060] ESI-TOF HRMS: m / z=965.4076; [M + +Na], calculated value m / z = 965.4070.

[0061] 31 P NMR (CD₂Cl₂): d 134.4 (d, J PP =13Hz); 145.6 (d,J) PP =13Hz)ppm.

[0062] 1H NMR(CD2Cl2):d 1.25(s,9H); 1.38(s,9H); 1.46(s,9H); 1.48(s,9H); 6.64(m,2H); 6.85(m, 1H); 6.99-7.13(m,19H); 7.33-7.38(m,3H); 7.44(m,1H),7.67(m,2H)ppm.

[0063] 5-(tert-butyl)-2-((3,3'-di-tert-butyl-5,5'-dimethoxy-2'-((4,4,5,5-tetraphenyl-1,3,2- Dioxaphosphane-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphane Synthesis of pentadiene (5):

[0064]

[0065] A mixture of 4-tert-butylcatechol (0.1133 g; 0.6818 mmol) and triethylamine (0.38 ml) in 3 ml of toluene was added dropwise to a solution of 4,4,5,5-tetraphenyl-2-((3,3',5,5'-tetratert-butyl-2'-((dichlorophosphonyl)oxy)-[1,1'-biphenyl]-2-yl)oxy)-1,3,2-dioxaphosphacyclopentane (0.618 g; 0.682 mmol) in 5 ml of toluene. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under vacuum. The obtained solid was dried at 60 °C / 0.1 mbar for 2 h and absorbed in 6 ml of hot acetonitrile. The solid formed after storing the solution in a deep freezer was filtered off, washed with slightly cooled acetonitrile, and dried under vacuum. Yield: 0.416 g (0.477 mmol, 70%).

[0066] Elemental analysis (C 64 H 72 Calculated value of O6P2 = 999.215 g / mol: C = 76.75 (76.93); H = 7.20 (7.26); P = 6.15 (6.20).

[0067] ESI-TOF HRMS: m / z=1021.4708; [M + +Na], calculated value m / z = 1021.4696.

[0068] 31 P NMR (CD₂Cl₂): d 136.2 (d, J) PP =10Hz); 136.3 (d,J) PP =10Hz); 145.7 (d,J) PP =10Hz); 145.8 (d,J) PP =10Hz)ppm. Two diastereomers.

[0069] 1H NMR(CD2Cl2):d 1.24+1.25(2s,9H); 1.35+1.37+1.38(3s,18H); 1.45+1.48+1.49(3s,18H); 6.53(m,2H);6.79(m,1H);6.96-7.18(m,18H);7.31-7.46(m,4H);7.64(t;J HH =2.3Hz; 1H), 7.67(d; J HH =2.5Hz; 1H)ppm.

[0070] 4,6-Di-tert-butyl-2-((3,3',5,5'-tetra-tert-butyl-2'-((4,4,5,5-tetraphenyl-1,3,2-dioxane) Phosphacyclopentane-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphacyclopentadiene Synthesis of (6):

[0071]

[0072] A mixture of 3,5-di-tert-butylcatechol (0.1602 g; 0.7207 mmol) and triethylamine (0.40 ml) in 3 ml of toluene was added dropwise to a solution of 4,4,5,5-tetraphenyl-2-((3,3',5,5'-tetratert-butyl-2'-((dichlorophosphonyl)oxy)-[1,1'-biphenyl]-2-yl)oxy)-1,3,2-dioxaphosphacyclopentane (0.6529 g; 0.7207 mmol) in 5 ml of toluene. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under vacuum. The obtained solid was dried at 60 °C / 0.1 mbar for 2 h, then stirred in 7 ml of acetonitrile for 1.5 h, filtered, and then dried under vacuum. Yield: 0.5345 g (0.5064 mmol, 70%).

[0073] Elemental analysis (C 68 H 80 Calculated value of O6P2 = 1055.322 g / mol): C = 77.49 (77.39); H = 7.57 (7.64); P = 5.90 (5.87).

[0074] ESI-TOF HRMS: m / z=1077.5305; [M + +Na], calculated value m / z = 1077.5322.

[0075] 31 P NMR (CD₂Cl₂): d 132.5 (d, J) PP =20Hz);134.4(s,br);144.3(d,J PP =20Hz); 145.3 (d,J) PP =11Hz)ppm. Two diastereomers.

[0076] 1 H NMR (CD2Cl2): δ 1.19 (s; 4.5H); 1.24 (s; 4.5H); 1.31 (s; 4.5H); 1.33 (s; 4.5H); 1.34 (s; 4.5H); 1.37 (s; 4.5H); 1.41 (s; 4.5H); 1.44 (s; 4.5H); 1.45 (s, 9H); 1.47 (s; 4.5H); 1.49 (s, 4.5H); 6.42 (m, 1H); 6.73 (m; 0.5H); 6.85 (dd, J HH =20.3 Hz; J HH =1.99 Hz; 1H); 6.96-7.16 (m, 16H); 7.23-7.30 (m; 1.5H); 7.31-7.43 (m, 4H); 7.60 (dd, J HH =12.5 Hz; J HH =2.4 Hz; 1H), 7.66 (dd, J HH =8.5 Hz; J HH =2.5 Hz; 1H) ppm.

[0077] Catalysis experiment

[0078] Hydroformylation was carried out in a 200 ml autoclave from Premex Reactor AG, Switzerland, equipped with a pressure maintaining device, gas flow meter, gas bubbling agitator, and pressure pipette. To minimize the effects of moisture and oxygen, toluene, used as a solvent, was purified in a Pure Solv.MD-7 system and stored under argon. The olefin “cis / trans-2-pentene” (Aldrich), used as a substrate, was heated under reflux on sodium and distilled under argon. In the autoclave, toluene solutions of the catalyst precursor and ligand were mixed under an argon atmosphere. [(acac)Rh(COD)] (Umicore, acac = acetylacetonate anion; COD = 1,5-cyclooctadiene) was used as the catalyst precursor. The autoclave was heated at 12 bar with stirring (1500 rpm) to reach a final pressure of 20 bar. After reaching the reaction temperature, the olefin was injected into the autoclave using an overpressure established in a pressure pipette. The reaction was carried out at a constant pressure (obtained from a closed-loop pressure controller (Nachdruckregler) from Bronkhorst, Netherlands) for 4 hours. After the reaction time was completed, the autoclave was cooled to room temperature, depressurized with stirring, and flushed with argon. Immediately after the stirrer was turned off, 1 ml of the reaction mixture was taken out in each case, diluted with 10 ml of pentane, and analyzed by gas chromatography: HP 5890 Series II plus, PONA, 50 m × 0.2 mm × 0.5 μm.

[0079] The reaction was carried out using compounds (1) to (6) according to the invention and using a contrasting ligand (D-1).

[0080]

[0081] Reaction conditions:

[0082] Olefin: 2-pentene, Solvent: toluene, Rhodium mass ratio: 100 ppm, p: 20 bar, T: 120 °C; t: 4 hours, Rh:ligand ratio = 1:2.

[0083] The results are summarized in the table below:

[0084] 1* 99 2* 99 3* 99 4* 99 5* 99 6* 99 D-1 14

[0085] *Compounds according to the present invention

[0086] As the experimental results show, the aforementioned technical problem is solved by the compound according to the present invention.

Claims

1. Compounds of formula (I): （I） in R 1 R 2 R 3 R 4 R 5 R 6 R 7 R 8 Each can be independently selected from: -H, -C1-C 12 -alkyl, -O-C1-C 12 -alkyl.

2. The compound according to claim 1, wherein R 5 and R 8 It is -C1-C 12 -alkyl.

3. The compound according to claim 1, wherein R 5 and R 8 It is - tert-butyl.

4. The compound according to any one of claims 1 to 3, wherein R 6 R 7 Selected from: -C1-C 12 -alkyl, -O-C1-C 12 -alkyl.

5. The compound according to any one of claims 1 to 3, wherein R 6 and R 7 It is -OCH3 or -tert-butyl.

6. The compound according to any one of claims 1 to 3, wherein R 1 R 2 R 3 R 4 Selected from -H, -C1-C 12 -alkyl.

7. The compound according to any one of claims 1 to 3, wherein R 1 R 2 R 3 R 4 It is -H or -tert-butyl.

8. The compound according to any one of claims 1 to 3, wherein the compound has one of structures 1 to 6: 。 9. A method for hydroformylating an olefinic unsaturated compound, comprising the following steps: a) Initially feeding an olefinic unsaturated compound selected from: ethylene, propylene, 1-butene, cis- and / or trans-2-butene, isobutene, 1,3-butadiene, 1-pentene, cis- and / or trans-2-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, hexene, tetramethylethylene, heptene, 1-octene, 2-octene, di-n-butene, or mixtures thereof; b) Adding a compound according to any one of claims 1 to 8 and a substance comprising Rh, wherein the Rh-containing substance is selected from: Rh(acac)(CO)2; [(acac)Rh(COD)], wherein acac = acetylacetonate anion; COD = 1,5-cyclooctadiene; Rh4CO 12 ; c) Input H2 and CO, d) Heating the reaction mixture obtained from a) to c) wherein the olefinic unsaturated compound is converted into an aldehyde.

10. The method of claim 9, wherein in step c), CO is introduced at a pressure in the range of 1 to 6 MPa, i.e., 10 to 60 bar.

11. The method according to claim 9 or 10, wherein in step d), the reaction mixture is heated to a temperature in the range of 80°C to 160°C.

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