Benzopinacol-based bisphosphite ligand

Abstract

To provide novel compounds which deliver an increased yield in hydroformylation of olefins.SOLUTION: The invention provides compounds represented by (I) in the figure.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to benzopinacol-based bisphosphite ligands and their use in hydroformylation.

Background Art

[0002] Patent Document 1 describes a hydroformylation method using a bisphosphite ligand. In particular, the use of ligand (D-1) is described.

[0003]

Chemical Formula

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The technical problem to be solved by the present invention is to provide a novel compound that brings about an increase in yield in the hydroformylation of olefins as compared to compounds known from the prior art.

[0006] This problem is solved by the compound according to claim 1. Formula (I):

[0007]

Chemical Formula

[0008] (wherein R 1 , R 2 , R 3 , R 4 , R 5 , R6 , R 7 , R 8 are each independently selected from -H, -(C1-C 12 )-alkyl, -O-(C1-C 12 ).) of the compound.

[0009] The expressions "-(C1-C 12 )-alkyl" and "-O-(C1-C 12 )-alkyl" include linear and branched alkyl groups having 1 to 12 carbon atoms. These are preferably -(C1-C8)-alkyl groups or -O-(C1-C8)-alkyl groups, particularly preferably -(C1-C4)-alkyl groups or -O-(C1-C4)-alkyl groups.

[0010] In one embodiment, R 5 and R 8 are -(C1-C 12 ).) In one embodiment, R 5 and R 8 are - tert Bu. In one embodiment, R 6 , R 7 are selected from -(C1-C 12 ), -O-(C1-C 12 ).) In one embodiment, R 6 and R 7 are -OCH3 or - tert Bu. In one embodiment, R 1 , R 2 , R 3 , R 4 are selected from -H, -(C1-C 12 ).) In one embodiment, R 1 , R 2 , R 3 , R 4 are -H or - tert Bu. In one embodiment, the compound has one of structures (1) to (6):

[0011]

Chemical formula

[0012] and has one of them. In addition to the compound itself, a method of using the compound is also claimed.

[0013] a) First, an ethylenically unsaturated compound is introduced, b) The above compound and a substance containing Rh are added, c) H2 and CO are introduced, d) The reaction mixture from steps a) to c) is heated to convert the ethylenically unsaturated compound into an aldehyde A method having the steps.

[0014] In this method, steps a), b), and c) can be carried out in any order. However, usually for CO, it is added after first introducing the co-reactants in steps a) and b). Further, CO may be introduced in two or more steps, for example, by first introducing a part of CO, then heating the mixture, and then introducing the other part of CO.

[0015] The ethylenically unsaturated compound used as a reactant in the method according to the present invention has one or more carbon-carbon double bonds. For the sake of simplicity, these compounds are hereinafter also referred to as olefins. The double bond may be terminal or internal.

[0016] In a variant of the method, the ethylenically unsaturated compound contains no further functional groups other than the carbon-carbon double bond.

[0017] In a variant of the method, the ethylenically unsaturated compound is selected from ethene, propene, 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 a mixture thereof.

[0018] In a variant of the method, the Rh-containing substance is Rh(acac)(CO)2, [(acac)Rh(COD)] (Umicore, acac = acetylacetonate anion; COD = 1,5-cyclooctadiene), Rh4CO 12 selected from.

[0019] In a variant of the method, CO is introduced in step c) at a pressure in the range of 1 to 6 MPa (10 to 60 bar).

[0020] In a variant of the method, the reaction mixture is heated in step d) to a temperature in the range of 80 °C to 160 °C.

[0021] The present invention will be described in more detail below with reference to examples.

Examples

[0022] Synthesis of 2-((3,3'-di-tert-butyl-5,5'-dimethoxy-2'-((4,4,5,5-tetraphenyl-1,3,2-dioxaphospholan-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphole (1)

[0023]

Chemical formula

[0024] To a solution of 2-((3,3'-di-tert-butyl-2'-((dichlorophosphanyl)oxy)-5,5'-dimethoxy-[1,1'-biphenyl]-2-yl)oxy)-4,4,5,5-tetraphenyl-1,3,2-dioxaphospholane (0.639 g, 0.7483 mmol) in toluene (6 mL) was added dropwise a mixture of catechol (0.0824 g, 0.7483 mmol) and triethylamine (0.42 mL) in toluene (3 mL) at room temperature. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under reduced pressure. The resulting solid was dried at 60 °C / 0.1 mbar for 2 h and taken up in hot acetonitrile (6.5 mL). The solid formed after cooling was filtered off, washed with a small amount of cold acetonitrile, and dried under reduced pressure. Yield: 0.426 g (0.5537 mmol, 74%). Elemental analysis (C 54 H 52 Calculated for C ESI-TOF HRMS: m / z = 891.3212; [M + + H], calculated m / z = 891.3215. 31 P NMR (CD2Cl2): δ 136.0 (d, J PP = 55 Hz); 146.9 (d, J PP = 55 Hz). 1 H NMR (CD2Cl2): δ 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.

[0025] Synthesis of 5-(tert-butyl)-2-((3,3'-di-tert-butyl-5,5'-dimethoxy-2'-((4,4,5,5-tetraphenyl-1,3,2-dioxaphospholane-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphole (2)

[0026]

Chem.

[0027] To a solution of 2-((3,3'-di-tert-butyl-2'-((dichlorophosphanyl)oxy)-5,5'-dimethoxy-[1,1'-biphenyl]-2-yl)oxy)-4,4,5,5-tetraphenyl-1,3,2-dioxaphospholane (0.4384 g, 0.5135 mmol) in toluene (4 mL) was added dropwise a mixture of 4-tert-butylcatechol (0.0853 g, 0.5135 mmol) and triethylamine (0.29 mL) in toluene (2 mL) at room temperature. The mixture was stirred overnight and filtered, and the filtrate was concentrated to dryness under reduced pressure. The resulting solid was dried at 60 °C / 0.1 mbar for 2 h and then taken up in hot acetonitrile (4.3 mL). The solid formed after cooling was filtered off, washed with a small amount of cold acetonitrile, and dried under reduced pressure. Yield: 0.201 g (0.261 mmol, 51%). Elemental analysis (C 58 H 60 O8P2, calculated = 947.052 g / mol): C = 73.51 (73.56); H = 6.63 (6.39); P = 6.81 (6.54). ESI-TOF HRMS: m / z = 696.3655; [M + +Na], calculated m / z = 696.3660. 31 P NMR (CD2Cl2): δ 135.7 (d, J PP = 44 Hz); 136.0 (d, J PP = 55 Hz); 145.0 (d, J PP = 55 Hz); 145.1 (d, J PP = 44 Hz) ppm. 11H NMR (CD2Cl2): δ 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.

[0028] Synthesis of 4,6 - Di - tert - butyl - 2 - ((3,3’ - di - tert - butyl - 5,5’ - dimethoxy - 2’ - ((4,4,5,5 - tetraphenyl - 1,3,2 - dioxaphospholan - 2 - yl)oxy)-[1,1’ - biphenyl]-2 - yl)oxy)benzod[d][1,3,2]dioxaphosphole (3)

[0029]

Chem.

[0030] To the solution of L1 in THF (4 mL), the - BuLi solution is added dropwise at - 20 °C. The mixture is stirred for an additional 20 minutes, then warmed to room temperature, and then the benzopinacol phosphorochloridite dissolved in THF (1.8 mL) is added dropwise. The reaction mixture is stirred overnight. Subsequently, triethylamine A is added, and then the phosphorus trichloride solution in THF (1.5 mL) is added dropwise to the reaction mixture cooled to 0 °C. The mixture is warmed to room temperature and stirred for 6 hours. The volatile components are removed from the mixture under reduced pressure, and the residue is dried at 60 °C and 0.1 - 0.5 mbar for 2 hours. The obtained solid is taken up in toluene (8 mL). To the obtained suspension, a mixture consisting of 3,5 - di - tert - butylcatechol, triethylamine B, and toluene (3 mL) is added dropwise at room temperature. The mixture is stirred overnight, filtered (G4), the solvent is removed under reduced pressure, and the solid is dried at 60 °C and 0.1 - 0.5 mbar. Crude yield: 1.03 g (95%). The crude product is dissolved in boiling acetonitrile (11 mL). The mixture is first slowly cooled to room temperature and then stored at -30°C overnight. The deposited solid is isolated by removing the supernatant mother liquor using an immersion frit while cooling to -30°C, and then dried under reduced pressure at 60°C for 5 hours. Yield: 0.786 g (72%). Elemental analysis (C 62 H 68 Calculated for O8P2 = 1,003.16 g / mol): C = 74.24 (74.23); H = 6.85 (6.83); P = 6.07 (6.18). ESI-TOF HRMS: m / z = 1025.4309; [M + +H], calculated m / z = 1025.4287. 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. 1 H 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).

[0031] Synthesis of 2-((3,3',5,5'-tetra-tert-butyl-2'-((4,4,5,5-tetraphenyl-1,3,2-dioxaphospholan-2-yl)oxy)-[1,1'-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphole (4)

[0032] [ka]

[0033] To a solution of toluene (5 mL) of 4,4,5,5-tetraphenyl-2-((3,3’,5,5’-tetra-tert-butyl-2’-((dichlorophosphanyl)oxy)-[1,1’-biphenyl]-2-yl)oxy)-1,3,2-dioxaphospholane (0.7936 g, 0.8760 mmol), a mixture of catechol (0.0964 g, 0.8760 mmol) and triethylamine (0.49 mL) in toluene (3 mL) is added dropwise at room temperature. The mixture is stirred overnight and filtered, and the filtrate is concentrated to dryness under reduced pressure. The obtained solid is dried at 60 °C / 0.1 mbar for 2 h, and then stirred in acetonitrile (7 mL) for 1 h. The remaining solid is filtered off, washed with a small amount of cold acetonitrile, and dried under reduced pressure. Yield: 0.6197 g (0.657 mmol, 75%). Elemental analysis (C 60 H 64 Calculated for C ESI-TOF HRMS: m / z = 965.4076; [M + +Na], calculated m / z = 965.4070. 31 P NMR (CD2Cl2): δ 134.4 (d, J PP = 13 Hz); 145.6 (d, J PP = 13 Hz) ppm. 1 H NMR (CD2Cl2): δ 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.

[0034] Synthesis of 5-(tert-butyl)-2-((3,3’-di-tert-butyl-5,5’-dimethoxy-2’-((4,4,5,5-tetraphenyl-1,3,2-dioxaphospholane-2-yl)oxy)-[1,1’-biphenyl]-2-yl)oxy)benzo[d][1,3,2]dioxaphosphole (5)

[0035]

Chem.

[0036] To a solution of 4,4,5,5-tetraphenyl-2-((3,3’,5,5’-tetra-tert-butyl-2’-((dichlorophosphanyl)oxy)-[1,1’-biphenyl]-2-yl)oxy)-1,3,2-dioxaphospholane (0.618 g, 0.682 mmol) in toluene (5 mL) is added dropwise a mixture of 4-tert-butylcatechol (0.1133 g, 0.6818 mmol) and triethylamine (0.38 mL) in toluene (3 mL) at room temperature. The mixture is stirred overnight and filtered, and the filtrate is concentrated to dryness under reduced pressure. The obtained solid is dried at 60 °C / 0.1 mbar for 2 h and taken up in hot acetonitrile (6 mL). The solid formed after storing the solution in the freezer is filtered off, washed with a small amount of cold acetonitrile, and dried under reduced pressure. Yield: 0.416 g (0.477 mmol, 70%). Elemental analysis (C 64 H 72 Calculated for C ESI-TOF HRMS: m / z = 1021.4708; [M + +Na]+, calculated m / z = 1021.4696. 31 31P NMR (CD2Cl2): δ 136.2 (d, J PP = 10 Hz); 136.3 (d, J PP = 10 Hz); 145.7 (d, J PP = 10 Hz); 145.8 (d, J PP = 10 Hz) ppm. Two diastereomers. 11H NMR (CD2Cl2): δ 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 = 2.3 Hz; 1H), 7.67 (d; J HH = 2.5 Hz; 1H) ppm.

[0037] Synthesis of 4,6 - Di - tert - butyl - 2 - ((3,3’,5,5’ - tetra - tert - butyl - 2’ - ((4,4,5,5 - tetraphenyl - 1,3,2 - dioxaphospholan - 2 - yl)oxy) - [1,1’ - biphenyl] - 2 - yl)oxy)benzo[d][1,3,2]dioxaphosphole (6)

[0038]

Chemical Structure

[0039] To a solution of 4,4,5,5 - tetraphenyl - 2 - ((3,3’,5,5’ - tetra - tert - butyl - 2’ - ((dichlorophosphanyl)oxy) - [1,1’ - biphenyl] - 2 - yl)oxy) - 1,3,2 - dioxaphospholane (0.6529 g, 0.7207 mmol) in toluene (5 mL), a mixture of 3,5 - di - tert - butylcatechol (0.1602 g, 0.7207 mmol) and triethylamine (0.40 mL) in toluene (3 mL) is added dropwise at room temperature. The mixture is stirred overnight, filtered, and the filtrate is concentrated to dryness under reduced pressure. The resulting solid is dried at 60 °C / 0.1 mbar for 2 hours, then stirred in acetonitrile (7 mL) for 1.5 hours, filtered, and dried under reduced pressure. Yield: 0.5345 g (0.5064 mmol, 70%). Elemental analysis (C 68 H 80 Calculated for C ESI-TOF HRMS: m / z = 1077.5305; [M + +Na], calculated m / z = 1077.5322. 31 P NMR (CD2Cl2): δ 132.5 (d, J PP = 20 Hz); 134.4 (s, br); 144.3 (d, J PP = 20 Hz); 145.3 (d, J PP = 11 Hz) ppm. Two diastereomers. 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.

[0040] Catalyst experiment Hydroformylation was carried out in a 200 mL autoclave (manufactured by Premex Reactor AG, Lengnau, Switzerland) equipped with a pressure holding valve, a gas flow meter, a sparging stirrer, and a pressure pipette. To minimize the influence of moisture and oxygen, toluene used as a solvent was purified with a Pure Solv. MD-7 System and stored under argon. The olefin cis / trans-2-pentene (Aldrich) used as a substrate was refluxed and heated over sodium and distilled under argon. Toluene solutions of the catalyst precursor and the ligand were mixed in the autoclave 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 to a final pressure of 20 bar at 12 bar while stirring (1,500 rpm). After reaching the reaction temperature, the olefin was injected into the autoclave by positive pressure prepared with a pressure pipette. The reaction was carried out for 4 hours at a constant pressure (closed-loop pressure controller manufactured by Bronkhorst, Netherlands). At the end of the reaction time, the autoclave was cooled to room temperature, depressurized while stirring, and purged with argon. Immediately after turning off the stirrer switch, 1 mL of each reaction mixture was taken out, diluted with 10 mL of pentane, and analyzed by gas chromatography. HP5890 Series II Plus, PONA, 50 m × 0.2 mm × 0.5 μm.

[0041] The reactions were carried out using the compounds (1) to (6) according to the present invention and the comparative ligand (D-1).

[0042]

Chemical formula

[0043] Reaction conditions Olefin: 2-pentene, solvent: toluene, mass ratio of rhodium: 100 ppm, pressure (p): 20 bar, temperature (T): 120 °C, time (t): 4 hours, Rh: ligand ratio = 1:2. The results are summarized in the following table.

[0044]

Table 1

[0045] As shown by the experimental results, the problem is solved by the compound according to the present invention.

Claims

1. Compound of formula (I): 【Chemical 1】 (wherein, R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ are each independently selected from -H, -(C １ -C １２ )-alkyl, -O-(C １ -C １２ )-alkyl.).

2.

3. Said R ５ and said R ８ are -(C １ -C １２ )-alkyl, the compound according to claim 1.

4. Said R ５ and said R ８ are - ｔｅｒｔ Bu, the compound according to claim 1.

5. Said R ６ and said R ７ are selected from -(C １ -C １２ )-alkyl and -O-(C １ -C １２ )-alkyl, the compound according to claim 1.

6. said R ６ and said R ７ is -OCH ３ or - ｔｅｒｔ Bu, the compound according to claim 1.

7. Said R １ 、said R ２ 、said R ３ 、said R ４ is selected from -H, -(C １ -C １２ )-alkyl, the compound according to claim 1.

8. Said R １ 、said R ２ 、said R ３ 、said R ４ is -H or - ｔｅｒｔ Bu, the compound according to claim 1. Structures (1) to (6): The compound according to claim 1, having one of [Chemical 2]

9. a) First, an ethylenically unsaturated compound is introduced, b) The compound according to claim 1 and a substance containing Rh are added, d) The reaction mixture from a) to c) is heated to convert the olefin to an aldehyde c) H ２ and CO are introduced, A method having the steps.

10. The ethylenically unsaturated compound in step a) is selected from ethene, propene, 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 a mixture thereof. The method according to claim 9.

11.

12. The substance containing Rh is Rh(acac)(CO) ２ , [(acac)Rh(COD)] (Umicore, acac = acetylacetonate anion, COD = 1,5-cyclooctadiene), Rh ４ CO １２ The method according to claim 9, selected from In step c), the CO is introduced at a pressure in the range of 1 to 6 MPa (10 to 60 bar). The method according to claim 9.

13. In step d), the reaction mixture is heated to a temperature in the range of 80°C to 160°C. The method according to claim 9. ​

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