Heterocyclic triptycene mononuclear metal rhodium complex as well as preparation and application thereof

Abstract

The invention belongs to the technical field of metal catalyst preparation, and provides a heterocyclic triptycene mononuclear metal rhodium complex and preparation and application thereof.The structural formula I of the heterocyclic triptycene mononuclear metal rhodium complex is shown in the specification, and the heterocyclic triptycene mononuclear metal rhodium complex has the advantages of being high in stability and activity and wide in substrate application range; and the compound has the advantages of simple synthesis steps, high yield and low cost, is suitable for various different metal catalytic reactions when being used as a catalyst, and has high popularization and application values.

Description

Technical Field

[0001] This application relates to the field of metal catalyst preparation technology, and in particular to a heterocyclic triterpenoid mononuclear rhodium complex and its preparation and application. Background Technology

[0002] Metal catalysts, due to their unique electronic structure and tunable active centers, exhibit extremely rich reactivity in organic synthesis, becoming core tools for constructing complex molecular frameworks. These catalysts significantly lower the activation energy of reactions by providing highly efficient active sites, enabling transformations that previously required harsh conditions to be achieved under milder conditions (such as ambient temperature and pressure or low temperature). Furthermore, precise regioselectivity and stereoselectivity can be achieved through ligand design or support modulation. Therefore, metal catalysts are the most widely used catalysts in various organic chemical reactions such as hydrogenation, coupling, and cycloaddition. In hydrogenation reactions, noble metal catalysts such as platinum, palladium, and rhodium can efficiently activate H2 molecules, achieving selective reduction of alkenes, alkynes, carbonyl compounds, and even aromatic rings. For example, asymmetric hydrogenation reactions can synthesize optically pure drug intermediates using rhodium catalysts modified with chiral ligands. Cross-coupling reactions (such as Suzuki, Heck, and Negishi couplings) rely on the d-electron modulation capabilities of palladium or nickel catalysts to achieve efficient carbon-carbon bond construction. These reactions have become key methods for the synthesis of drug molecules (such as antitumor drugs and antibiotics) and functional materials. Over the past few decades, metal catalysts have been widely used in laboratory research, pharmaceuticals, and fine chemicals to synthesize many types of organic compounds due to their advantages such as mild reaction conditions, wide substrate applicability, non-toxic byproducts, and easy product handling.

[0003] Taking the Suzuki reaction as an example, the Suzuki reaction is one of the most commonly used aromatic ring coupling reactions, and palladium catalysts are the most commonly used catalysts. This type of catalytic system has been extensively studied. Because palladium catalysts have relatively high stability to air and heat, are easy to recover and reuse in catalytic reactions, and have high reaction activity, and some of the more mature systems can catalyze the coupling of activated and unactivated chlorobenzene and phenylboronic acid under relatively mild conditions, it has become one of the most important means of modern organic synthesis and has been applied to many fields of organic molecule synthesis.

[0004] Despite significant progress in metal catalyst research over the past few decades, their industrial application still faces multiple challenges and bottlenecks. The contradiction between high cost and stability is a core constraint. While precious metal catalysts (such as platinum, palladium, and rhodium) exhibit excellent activity, they are expensive and prone to deactivation due to sintering, poisoning, or carbon buildup. The complexity of ligand and support design further exacerbates the application difficulties. For example, while chiral phosphine ligands can improve the selectivity of asymmetric hydrogenation reactions, their synthesis is cumbersome and sensitive to air, while the microporous structure of molecular sieve supports may limit the mass transfer efficiency of macromolecular substrates. Furthermore, insufficient recycling and regeneration technologies lead to resource waste. For instance, the vanadium, nickel, and other metals contained in degraded residue hydrogenation catalysts, if not effectively recovered, not only cause economic losses of hundreds of billions of yuan annually but also lead to heavy metal pollution. Therefore, metal catalysts with high stability, high activity, broad substrate applicability, recyclability, low cost, and high TON and TOF remain crucial research areas. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a heterocyclic triptene mononuclear rhodium complex and its preparation and application. It has the advantages of high stability, high activity, and wide substrate applicability. Moreover, the synthesis steps of this type of compound are simple, the yield is high, and the cost is low. When used as a catalyst, it is suitable for various metal catalytic reactions and has high application value.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] The first aspect of this invention provides a heterocyclic triptene mononuclear rhodium complex, the structural formula of which is as follows:

[0008] ,

[0009] In structural formula I, R1 is selected from any one of -H, -F, -CN, -CF3, substituted or unsubstituted alkyl groups with 1 to 5 carbon atoms, fused phenyl groups, or fused cyclopentyl groups;

[0010] R2, R3, and R4 are each independently selected from any one of the following: -H, -D, -Cl, -F, -CN, -CD3, -CF3, -OCF3, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted alkoxy groups with 1 to 10 carbon atoms, straight-chain substituted or unsubstituted olefinic groups with 2 to 10 carbon atoms, fluorinated substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, fluorinated substituted or unsubstituted alkoxy groups with 1 to 10 carbon atoms, fluorinated substituted or unsubstituted olefinic groups with 2 to 10 carbon atoms, substituted or unsubstituted aryl groups with 5 to 20 carbon atoms, substituted or unsubstituted heteroaryl groups with 5 to 20 carbon atoms, substituted or unsubstituted fused-ring aryl groups with 5 to 20 carbon atoms, or substituted or unsubstituted heterofused-ring aryl groups with 5 to 20 carbon atoms.

[0011] R5 is selected from any one of -H, -D, -Cl, -F, -CN, -CD3, -CF3, -CH3, or a benzene ring;

[0012] X represents Cl, Br, and I atoms.

[0013] A second aspect of this invention provides a method for preparing the above-mentioned heterocyclic triptene mononuclear rhodium complex, comprising the following steps:

[0014] (1) Aromatic hydrocarbons and their derivatives are mixed with ethylene acetate, and then subjected to addition reaction and purification to obtain hydroxyl compounds;

[0015] (2) The hydroxyl compound was mixed with p-benzoquinone, and then catalytically oxidized and purified to obtain a carbonyl compound;

[0016] (3) The carbonyl compound is mixed with 8-amino-7-aldehyde quinoline or a substituted product of 8-amino-7-aldehyde quinoline, and the intermediate ligand is obtained by condensation reaction and purification.

[0017] (4) The intermediate ligand, ligand precursor, rhodium halide, and sodium trifluoromethanesulfonate were mixed, and the mixture was coordinated and purified to obtain a heterocyclic triptene mononuclear rhodium complex.

[0018] Furthermore, the reaction conditions in step (1) satisfy at least one of the following conditions (a) to (c):

[0019] (a) Aromatic hydrocarbons and their derivatives are selected from anthracene, tetraphenyl or 2,3-dicyanoanthracene;

[0020] (b) An addition reaction is carried out in a system of potassium tert-butoxide and tetrahydrofuran;

[0021] (c) Purification includes alumina column chromatography and dichloromethane elution.

[0022] Furthermore, the reaction conditions in step (2) satisfy at least one of the following conditions (d) to (e):

[0023] (d) Catalytic oxidation reaction was carried out in a reaction system of aluminum tritert-butoxy and tetrahydrofuran;

[0024] (e) Purification includes alumina column chromatography and elution with a mixture of dichloromethane and petroleum ether.

[0025] Furthermore, the reaction conditions in step (3) satisfy at least one of the following conditions (f) to (h):

[0026] (f) The substituents of 8-amino-7-aldehyde quinoline are halogen elements;

[0027] (g) A condensation reaction is carried out in a reaction system of potassium tert-butoxide and tert-butanol;

[0028] (h) Purification includes alumina column chromatography and elution with a mixture of dichloromethane and ethyl acetate.

[0029] Further, in step (4), the ligand precursor is selected from cyclopentadiene, pentamethylcyclopentadiene or 1-trifluoromethyl-pentamethylcyclopentadiene.

[0030] Furthermore, in step (4), the rhodium halide is selected from rhodium trichloride, rhodium tribromide or rhodium triiodide.

[0031] Further, in step (4), coordination is carried out in a tetrahydrofuran solution of n-butyllithium.

[0032] A third aspect of the present invention provides the application of the above-mentioned heterocyclic tripterygene mononuclear rhodium complex, namely, applying the heterocyclic tripterygene mononuclear rhodium complex in a catalyst.

[0033] Furthermore, the application of catalysts includes the Suzuki reaction, the Buchwald-Hartwig reaction, the Heck reaction, the Still reaction, and the Negishi reaction.

[0034] The beneficial technical effects of this invention are as follows:

[0035] This invention relates to a heterocyclic triptene mononuclear rhodium complex, which is simple to prepare, has a high yield, and is suitable for a variety of substrates when used as a catalyst. The amount of catalyst required can be significantly reduced, and it exhibits good catalytic effects for various metal-catalyzed reactions. It has significant application value for researching the progress and application of catalytic reactions, reducing production costs, and expanding the applicable substrate range.

[0036] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Detailed Implementation

[0037] Unless otherwise defined, all technical and / or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should be understood that certain features of the invention (described in the context of separate embodiments for clarity) may also be provided in a single embodiment. Conversely, multiple features of the invention (described in the context of a single embodiment for brevity) may also be provided separately or in any suitable combination or, where appropriate, in any other described embodiment of the invention. Certain features described in the context of various embodiments will not be considered essential features of those embodiments unless the embodiment is inoperable without those elements. The invention is further illustrated below by specific examples; however, it should be noted that the specific process conditions and results described in the embodiments of the invention are merely illustrative and should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be covered within the scope of protection of the invention.

[0038] First, it should be noted that, unless otherwise specified, the preparation methods in this application are all conventional methods, and the raw materials can be obtained from publicly available commercial sources unless otherwise specified.

[0039] This invention provides a heterocyclic triterpenoid mononuclear rhodium complex, the structural formula of which is as follows:

[0040] ,

[0041] In structural formula I, R1 is selected from any one of -H, -F, -CN, -CF3, substituted or unsubstituted alkyl groups with 1 to 5 carbon atoms, fused phenyl groups, or fused cyclopentyl groups;

[0042] R2, R3, and R4 are each independently selected from any one of the following: -H, -D, -Cl, -F, -CN, -CD3, -CF3, -OCF3, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted alkoxy groups with 1 to 10 carbon atoms, straight-chain substituted or unsubstituted olefin groups with 2 to 10 carbon atoms, fluorinated substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, fluorinated substituted or unsubstituted alkoxy groups with 1 to 10 carbon atoms, fluorinated substituted or unsubstituted olefin groups with 2 to 10 carbon atoms, substituted or unsubstituted aryl groups with 5 to 20 carbon atoms, substituted or unsubstituted heteroaryl groups with 5 to 20 carbon atoms, substituted or unsubstituted fused-ring aryl groups with 5 to 20 carbon atoms, or substituted or unsubstituted heterofused-ring aryl groups with 5 to 20 carbon atoms.

[0043] R5 is selected from any one of -H, -D, -Cl, -F, -CN, -CD3, -CF3, -CH3, or a benzene ring;

[0044] X represents Cl, Br, and I atoms.

[0045] The present invention also provides a method for preparing the above-mentioned heterocyclic triptene mononuclear rhodium complex, comprising the following steps:

[0046] (1) Aromatic hydrocarbons and their derivatives are mixed with ethylene acetate, and hydroxyl compounds are obtained by addition reaction and purification.

[0047] Specifically, in this step:

[0048] Aromatic hydrocarbons are polycyclic aromatic hydrocarbons, and aromatic hydrocarbons and their derivatives are selected from anthracene, tetraphenylene or 2,3-dicyanoanthracene;

[0049] The addition reaction is carried out in the reaction system of potassium tert-butoxide and tetrahydrofuran;

[0050] Purification includes alumina column chromatography and dichloromethane elution.

[0051] (2) The hydroxy compound was mixed with p-benzoquinone, and then catalytically oxidized and purified to obtain the carbonyl compound.

[0052] Specifically, in this step:

[0053] Catalytic oxidation reaction was carried out in a reaction system of tritert-butoxyaluminum and tetrahydrofuran;

[0054] Purification involved alumina column chromatography followed by elution with a mixture of dichloromethane and petroleum ether.

[0055] (3) The carbonyl compound is mixed with 8-amino-7-aldehyde quinoline or its substituted derivatives, and the intermediate ligand is obtained by condensation reaction and purification.

[0056] Specifically, in this step:

[0057] The substituents of 8-amino-7-aldehyde quinoline are halogen elements;

[0058] The condensation reaction is carried out in the reaction system of potassium tert-butoxide and tert-butanol;

[0059] Purification involved alumina column chromatography followed by elution with a mixture of dichloromethane and ethyl acetate.

[0060] (4) The intermediate ligand, ligand precursor, rhodium halide, and sodium trifluoromethanesulfonate were mixed, and the mixture was coordinated and purified to obtain a heterocyclic triptene mononuclear rhodium complex.

[0061] Specifically, in this step:

[0062] The ligand precursor is selected from cyclopentadiene, pentamethylcyclopentadiene, or 1-trifluoromethyl-pentamethylcyclopentadiene;

[0063] Rhodium halides are selected from rhodium trichloride, rhodium tribromide, or rhodium triiodide;

[0064] Coordination was carried out in a tetrahydrofuran solution of n-butyllithium.

[0065] The present invention also provides the application of the above-mentioned heterocyclic tripterygene mononuclear rhodium complex, namely, applying the heterocyclic tripterygene mononuclear rhodium complex in a catalyst.

[0066] Furthermore, the applications of the aforementioned catalysts include the Suzuki reaction, the Buchwald-Hartwig reaction, the Heck reaction, the Still reaction, and the Negishi reaction.

[0067] The present invention will be described in detail below through specific examples and embodiments. It should also be understood that the following embodiments are only for specific illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of the present invention are within the scope of protection of the present invention. The specific process parameters, etc., in the following examples are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the appropriate range based on the description herein, and are not intended to be limited to the specific values ​​in the examples below.

[0068] Example 1: Preparation of Compound 1:

[0069]

[0070] (1) Preparation of compound 1a:

[0071]

[0072] To a 250 mL two-necked flask, add 1.8 g (10.0 mmol) anthracene, 947 mg (11.0 mmol) ethylene acetate, 1.7 g (15.0 mmol) potassium tert-butoxide, and 100 mL tetrahydrofuran. Stir the mixture at 40 °C for 3 h, remove the solvent, and perform alumina column chromatography. Elute with dichloromethane to give 2.1 g of a white solid of compound 1a, yield 94%.

[0073] Elemental analysis of compound 1a: Compound 1a (C 16 H 14 O), theoretical values: C, 86.45; H, 6.35. Measured values: C, 86.33; H, 6.29. Mass spectrometry (ESI): m / z 221.10 (M + ).

[0074] (2) Preparation of compound 1b:

[0075]

[0076] To a 250 mL two-necked flask, add 2.2 g (10.0 mmol) of compound 1a, 2.2 g (20.0 mmol) of p-benzoquinone, 2.5 g (10.0 mmol) of aluminum tritert-butoxy, and 100 mL of tetrahydrofuran. Stir the mixture at 40 °C for 5 h, remove the solvent, and elute by alumina column chromatography. Elute with dichloromethane:petroleum ether at a volume ratio of 1:4 to give 2.0 g of a white solid of compound 1b, with a yield of 91%.

[0077] Elemental analysis of compound 1b: Compound 1b (C 16 H 12 O), theoretical values: C, 87.25; H, 5.49. Measured values: C, 87.43; H, 5.39. Mass spectrometry (ESI): m / z 219.08 (M + ).

[0078] (3) Preparation of compound 1c:

[0079]

[0080] To a 250 mL two-necked flask, add 2.2 g (10.0 mmol) of compound 1b, 1.7 g (10.0 mmol) of 8-amino-7-aldehyde quinoline, 2.2 g (20.0 mmol) of potassium tert-butoxide, and 150 mL of tert-butanol. Stir the mixture at 80 °C for 4 h, remove the solvent, and elute by alumina column chromatography. The solution was washed with dichloromethane and ethyl acetate at a volume ratio of 1:2 to give 3.3 g of a white solid of compound 1c, with a yield of 93%.

[0081] Elemental analysis of compound 1c: Compound 1c (C 26 H 16 Theoretical values: C, 87.62; H, 4.52; N, 7.86. Measured values: C, 87.83; H, 4.48; N, 7.67. Mass spectrometry (ESI): m / z 355.12 (M + ).

[0082] (4) Preparation of compound 1:

[0083]

[0084] To a 250 mL two-necked flask, add 660 mg (10.0 mmol) cyclopentadiene and 100 mL THF. Add 4 mL of 2.5 M tetrahydrofuran solution of n-butyllithium dropwise at -78 °C. After the addition is complete, raise the temperature to room temperature and stir for 2 h. Add 2.1 g (10.0 mmol) rhodium trichloride and 1.7 g (10.0 mmol) sodium trifluoromethanesulfonate. Stir at room temperature for 1 h. Add 3.6 g (10.0 mmol) of compound 1c. Stir at room temperature for 2 h. Remove the solvent and perform alumina column chromatography. Elute with dichloromethane:ethyl acetate at a volume ratio of 1:1 to obtain 6.1 g of a yellow solid of compound 1, yield 86%.

[0085] Elemental analysis of compound 1: Compound 1 (C 32 H 20 ClF3N2O3RhS), theoretical values: C, 54.29; H, 2.85; N, 3.96. Measured values: C, 54.38; H, 2.88; N, 3.77. Mass spectrometry (ESI): m / z 705.98 (M + ).

[0086] Example 2: Preparation of Compound 2:

[0087]

[0088] (1) Preparation of compound 2a:

[0089]

[0090] 2.3 g (10.0 mmol) of tetraphenyl, 946 mg (11.0 mmol) of ethylene acetate, 1.7 g (15.0 mmol) of potassium tert-butoxide, and 100 mL of tetrahydrofuran were added to a 250 mL two-necked flask. The mixture was stirred at 40 °C for 3 h. The solvent was removed, and the mixture was subjected to alumina column chromatography. After elution with dichloromethane, 2.5 g of a white solid of compound 2a was obtained, with a yield of 91%.

[0091] Elemental analysis of compound 2a: Compound 2a (C 20 H 16 O), theoretical values: C, 88.20; H, 5.92. Measured values: C, 88.43; H, 5.86. Mass spectrometry (ESI): m / z 271.11 (M + ).

[0092] (2) Preparation of compound 2b:

[0093]

[0094] To a 250 mL two-necked flask, add 2.7 g (10.0 mmol) of compound 2a, 2.2 g (20.0 mmol) of p-benzoquinone, 2.5 g (10.0 mmol) of aluminum tritert-butoxy, and 100 mL of tetrahydrofuran. Stir the mixture at 40 °C for 5 h, remove the solvent, and elute by alumina column chromatography. The solution was washed with dichloromethane and petroleum ether at a volume ratio of 1:2 to give 2.3 g of a white solid of compound 2b, with a yield of 86%.

[0095] Elemental analysis of compound 2b: Compound 2b (C 20 H 14 O), theoretical values: C, 88.86; H, 5.22. Measured values: C, 88.51; H, 5.44. Mass spectrometry (ESI): m / z 269.10 (M + ).

[0096] (3) Preparation of compound 2c:

[0097]

[0098] To a 250 mL two-necked flask, add 2.7 g (10.0 mmol) of compound 2b, 1.7 g (10.0 mmol) of 8-amino-7-aldehyde quinoline, 2.2 g (20.0 mmol) of potassium tert-butoxide, and 150 mL of tert-butanol. Stir the mixture at 80 °C for 4 h, remove the solvent, and perform alumina column chromatography. Elute with dichloromethane:ethyl acetate = 1:4 to give 3.4 g of a yellow solid of compound 2c, yield 84%.

[0099] Elemental analysis of compound 2c: Compound 2c (C 30 H 18 N2), theoretical values: C, 88.64; H, 4.46; N, 6.89. Measured values: C, 88.92; H, 4.33; N, 6.71. Mass spectrometry (ESI): m / z 405.14 (M + ).

[0100] (4) Preparation of compound 2:

[0101]

[0102] To a 250 mL two-necked flask, add 1.4 g (10.0 mmol) of pentamethylcyclopentadiene and 100 mL of THF. Add 4 mL of 2.5 M tetrahydrofuran solution of n-butyllithium dropwise at -78 °C. After the addition is complete, raise the temperature to room temperature and stir for 2 h. Add 3.4 g (10.0 mmol) of rhodium tribromide and 1.7 g (10.0 mmol) of sodium trifluoromethanesulfonate. Stir for 1 h at room temperature. Add 4.1 g (10.0 mmol) of compound 2c. Stir for 2 h at room temperature. Remove the solvent and perform alumina column chromatography. Elute with dichloromethane:ethyl acetate at a volume ratio of 1:4 to obtain 7.2 g of an orange-yellow solid of compound 2, yield 82%.

[0103] Elemental analysis of compound 2: Compound 2 (C 41 H 33 (BrF3N2O3RhS), theoretical values: C, 56.37; H, 3.81; N, 3.21. Measured values: C, 56.44; H, 3.88; N, 3.37. Mass spectrometry (ESI): m / z 871.03 (M + ).

[0104] Example 3: Preparation of Compound 3:

[0105]

[0106] (1) Preparation of compound 3b:

[0107]

[0108] To a 250 mL two-necked flask, add 2.2 g (10.0 mmol) of compound 1b, 2.5 g (10.0 mmol) of compound 3a (5-bromo-8-amino-7-aldehyde quinoline), 2.2 g (20.0 mmol) of potassium tert-butoxide, and 150 mL of tert-butanol. Stir the mixture at 80 °C for 4 h, remove the solvent, and elute by alumina column chromatography. The solution was washed with dichloromethane and ethyl acetate at a volume ratio of 2:1 to give 3.6 g of a white solid of compound 3b, with a yield of 82%.

[0109] Elemental analysis of compound 3b: Compound 3b (C 26 H 15 (BrN2), theoretical values: C, 71.74; H, 3.47; N, 6.44. Measured values: C, 71.99; H, 4.42; N, 6.64. Mass spectrometry (ESI): m / z 433.03 (M + ).

[0110] (2) Preparation of compound 3c:

[0111]

[0112] To a 250 mL two-necked flask, add 4.4 g (10.0 mmol) of compound 3b, 1.5 g (10.0 mmol) of p-methoxyphenylboronic acid, 2.8 g (20.0 mmol) of potassium carbonate, 578 mg (0.5 mmol) of tetrakis(triphenylphosphine)palladium, and 150 mL of DMF. Stir the mixture at 100 °C for 4 h. After removing the solvent, precipitate the mixture by alumina column chromatography. Elute with petroleum ether:ethyl acetate at a volume ratio of 1:4 to obtain 4.3 g of a white solid of compound 3c, with a yield of 94%.

[0113] Elemental analysis of compound 3c: Compound 3c (C 33 H 22 N₂O), theoretical values: C, 85.69; H, 4.79; N, 6.06. Measured values: C, 85.33; H, 4.61; N, 6.34. Mass spectrometry (ESI): m / z 461.16 (M + ).

[0114] (3) Preparation of compound 3:

[0115]

[0116] To a 250 mL two-necked flask, add 1.9 g (10.0 mmol) of compound 3d (1-trifluoromethyl-pentamethylcyclopentadiene), 100 mL of THF, and 4 mL of 2.5 M tetrahydrofuran solution of n-butyllithium. After the addition is complete, raise the temperature to room temperature and stir for 2 h. Add 2.1 g (10.0 mmol) of rhodium trichloride and 1.7 g (10.0 mmol) of sodium trifluoromethanesulfonate, and stir for 1 h at room temperature. Add 4.6 g (10.0 mmol) of compound 3c, and stir for 2 h at room temperature. Remove the solvent and perform alumina column chromatography. Elute with dichloromethane:ethyl acetate at a volume ratio of 1:2 to obtain 7.7 g of a yellow-orange solid of compound 3, with a yield of 82%.

[0117] Elemental analysis of compound 3: Compound 3 (C 44 H 34 ClF6N2O4RhS), theoretical values: C, 56.27; H, 3.65; N, 2.95. Measured values: C, 56.83; H, 3.68; N, 2.77. Mass spectrometry (ESI): m / z 937.08 (M + ).

[0118] Example 4: Preparation of Compound 4:

[0119]

[0120] (1) Preparation of compound 4a:

[0121]

[0122] To a 250 mL two-necked flask, add 2.3 g (10.0 mmol) of 2,3-dicyanoanthracene, 947 mg (11.0 mmol) of ethylene acetate, 1.7 g (15.0 mmol) of potassium tert-butoxide, and 100 mL of tetrahydrofuran. Stir the mixture at 40 °C for 3 h, remove the solvent, and perform alumina column chromatography. Elute with dichloromethane to give 2.4 g of a white solid of compound 4a, with a yield of 89%.

[0123] Elemental analysis of compound 4a: Compound 4a (C 18 H 12 N₂O), theoretical values: C, 79.39; H, 4.44; N, 10.29. Measured values: C, 79.83; H, 4.41; N, 10.43. Mass spectrometry (ESI): m / z 271.09 (M + ).

[0124] (2) Preparation of compound 4b:

[0125]

[0126] To a 250 mL two-necked flask, add 2.7 g (10.0 mmol) of compound 4a, 2.2 g (20.0 mmol) of p-benzoquinone, 2.5 g (10.0 mmol) of aluminum tritert-butoxy, and 100 mL of tetrahydrofuran. Stir the mixture at 40 °C for 5 h, remove the solvent, and elute by alumina column chromatography. The solution was washed with dichloromethane and petroleum ether at a volume ratio of 2:1 to give 2.5 g of a yellow solid of compound 4b, with a yield of 92%.

[0127] Elemental analysis of compound 4b: Compound 4b (C 18 H 10 N₂O), theoretical values: C, 79.99; H, 3.73; N, 10.36. Measured values: C, 79.88; H, 3.61; N, 10.47. Mass spectrometry (ESI): m / z 269.07 (M + ).

[0128] (3) Preparation of compound 4c:

[0129]

[0130] To a 250 mL two-necked flask, add 2.7 g (10.0 mmol) of compound 4b, 1.7 g (10.0 mmol) of 8-amino-7-aldehyde quinoline, 2.2 g (20.0 mmol) of potassium tert-butoxide, and 150 mL of tert-butanol. Stir the mixture at 80 °C for 4 h, remove the solvent, and elute by alumina column chromatography. The solution was washed with dichloromethane and ethyl acetate at a volume ratio of 1:5 to obtain 3.7 g of a yellow solid of compound 4c, with a yield of 90%.

[0131] Elemental analysis of compound 4c: Compound 4c (C 28 H 14 N4), theoretical values: C, 82.74; H, 3.47; N, 13.78. Measured values: C, 82.38; H, 3.44; N, 13.74. Mass spectrometry (ESI): m / z 405.11 (M + ).

[0132] (4) Preparation of compound 4d:

[0133]

[0134] Under argon atmosphere, 4.1 g (10.0 mmol) of compound 4c, 6.5 g (15.0 mmol) of phosphorus pentabromide, and 11.5 g (40.0 mmol) of phosphorus tribromooxybromide were added to a 250 mL two-necked flask. The mixture was stirred at 80 °C for 6 h, and then poured into ice water. Concentrated ammonia was added to make the resulting mixture alkaline. The reaction mixture was extracted with chloroform, and the resulting organic layer was washed with water and dried over sodium sulfate. The solid was subjected to alumina column chromatography, eluted with dichloromethane and ethyl acetate in a volume ratio of 1:2, to give 4.4 g of a yellow solid of compound 4d, in 91% yield.

[0135] Elemental analysis of compound 4d: Compound 4d (C 28 H 13 (BrN4), theoretical values: C, 69.29; H, 2.70; N, 11.54. Measured values: C, 68.97; H, 2.66; N, 11.71. Mass spectrometry (ESI): m / z 483.02 (M + ).

[0136] (5) Preparation of compound 4e:

[0137] To a 250 mL two-necked flask, add 4.9 g (10.0 mmol) of compound 4d, 1.2 g (10.0 mmol) of phenylboronic acid, 2.8 g (20.0 mmol) of potassium carbonate, 578 mg (0.5 mmol) of tetrakis(triphenylphosphine)palladium, and 150 mL of DMF. Stir the mixture at 100 °C for 4 h. After removing the solvent, precipitate the mixture by alumina column chromatography. Elute with petroleum ether:ethyl acetate at a volume ratio of 2:1 to obtain 4.5 g of a yellow solid of compound 4e, with a yield of 93%.

[0138] Elemental analysis of compound 4e: Compound 4e (C 34 H 18 N4), theoretical values: C, 84.63; H, 3.76; N, 11.61. Measured values: C, 84.39; H, 4.66; N, 11.77. Mass spectrometry (ESI): m / z 481.14 (M + ).

[0139] (6) Preparation of compound 4:

[0140]

[0141] To a 250 mL two-necked flask, add 660 mg (10.0 mmol) cyclopentadiene and 100 mL THF. Add 4 mL of 2.5 M tetrahydrofuran solution of n-butyllithium dropwise at -78 °C. After the addition is complete, raise the temperature to room temperature and stir for 2 h. Add 2.1 g (10.0 mmol) rhodium trichloride and 1.7 g (10.0 mmol) sodium trifluoromethanesulfonate. Stir at room temperature for 1 h. Add 4.8 g (10.0 mmol) of compound 4e. Stir at room temperature for 2 h. Remove the solvent and perform alumina column chromatography. Elute with dichloromethane:ethyl acetate at a volume ratio of 1:4 to obtain 6.9 g of a yellow-orange solid of compound 4, yield 83%.

[0142] Elemental analysis of compound 4: Compound 4 (C 40 H 22 ClF3N4O3RhS), theoretical values: C, 57.60; H, 2.66; N, 6.72. Measured values: C, 57.83; H, 2.71; N, 6.84. Mass spectrometry (ESI): m / z 832.00 (M + ).

[0143] Example 5

[0144] Compound 1 prepared in Example 1 was used in the Suzuki coupling reaction:

[0145] In a Schlenk tube equipped with a magnetic stir bar, 1.5 mmol of phenylboronic acid, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 1) were added sequentially. Then, 1.0 mmol of p-methoxybromobenzene and 1 mL of isopropanol were added, and the mixture was stirred at 80 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0146] Example 6

[0147] Compound 2 prepared in Example 2 was used in the Suzuki coupling reaction:

[0148] In a Schlenk tube equipped with a magnetic stir bar, 1.5 mmol of phenylboronic acid, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 2) were added sequentially. Then, 1.0 mmol of p-methoxybromobenzene and 1 mL of isopropanol were added, and the mixture was stirred at 80 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0149] Example 7

[0150] Compound 3, prepared in Example 3, was used in the Suzuki coupling reaction:

[0151] In a Schlenk tube equipped with a magnetic stir bar, 1.5 mmol of phenylboronic acid, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 3) were added sequentially. Then, 1.0 mmol of p-methoxybromobenzene and 1 mL of isopropanol were added, and the mixture was stirred at 80 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0152] Example 8

[0153] Compound 4, prepared in Example 4, was used in the Suzuki coupling reaction:

[0154] In a Schlenk tube equipped with a magnetic stir bar, 1.5 mmol of phenylboronic acid, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 4) were added sequentially. Then, 1.0 mmol of p-methoxybromobenzene and 1 mL of isopropanol were added, and the mixture was stirred at 80 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0155] Example 9

[0156] Compound 1 prepared in Example 1 was used in the Hartwig-Buchwald coupling reaction:

[0157] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 1) were added sequentially. Then, 1.2 mmol of diphenylamine and 1 mL of toluene were added, and the mixture was stirred at 100 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0158] Example 10

[0159] Compound 2, prepared in Example 2, was used in the Hartwig-Buchwald coupling reaction:

[0160] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 2) were added sequentially. Then, 1.2 mmol of diphenylamine and 1 mL of toluene were added, and the mixture was stirred at 100 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0161] Example 11

[0162] Compound 3, prepared in Example 3, was used in the Hartwig-Buchwald coupling reaction:

[0163] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 3) were added sequentially. Then, 1.2 mmol of diphenylamine and 1 mL of toluene were added, and the mixture was stirred at 100 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0164] Example 12

[0165] Compound 4, prepared in Example 4, was used in the Hartwig-Buchwald coupling reaction:

[0166] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (compound 4) were added sequentially. Then, 1.2 mmol of diphenylamine and 1 mL of toluene were added, and the mixture was stirred at 100 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0167] Example 13

[0168] Compound 1 prepared in Example 1 was used in the Heck coupling reaction:

[0169] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-bromobenzoic acid, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 1) were added sequentially. Then, 1.2 mmol of acrylic acid and 1 mL of xylene were added, and the mixture was stirred at 120 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0170] Example 14

[0171] Compound 2 prepared in Example 2 was used in the Heck coupling reaction:

[0172] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-bromobenzoic acid, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 2) were added sequentially. Then, 1.2 mmol of acrylic acid and 1 mL of xylene were added, and the mixture was stirred at 120 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0173] Example 15

[0174] Compound 3, prepared in Example 3, was used in the Heck coupling reaction:

[0175] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-bromobenzoic acid, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 3) were added sequentially. Then, 1.2 mmol of acrylic acid and 1 mL of xylene were added, and the mixture was stirred at 120 °C for 2 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0176] Example 16

[0177] Compound 4, prepared in Example 4, was used in the Heck coupling reaction:

[0178] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-bromobenzoic acid, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 4) were added sequentially. Then, 1.2 mmol of acrylic acid and 1 mL of xylene were added, and the mixture was stirred at 120 °C for 2 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0179] Example 17

[0180] Compound 1 prepared in Example 1 was used in the Still coupling reaction:

[0181] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium fluoride, and 0.01% mmol of catalyst (compound 1) were added sequentially. Then, 1.2 mmol of tributylphenylene and 1 mL of dioxane were added, and the mixture was stirred at 100 °C for 6 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0182] Example 18

[0183] Compound 2 prepared in Example 2 was used for the Still coupling reaction:

[0184] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium fluoride, and 0.01% mmol of catalyst (compound 2) were added sequentially. Then, 1.2 mmol of tributylphenylene and 1 mL of dioxane were added, and the mixture was stirred at 100 °C for 6 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0185] Example 19

[0186] Compound 3, prepared in Example 3, was used in the Still coupling reaction:

[0187] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium fluoride, and 0.01% mmol of catalyst (compound 3) were added sequentially. Then, 1.2 mmol of tributylphenylene and 1 mL of dioxane were added, and the mixture was stirred at 100 °C for 6 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0188] Example 20

[0189] Compound 4, prepared in Example 4, was used in the Still coupling reaction:

[0190] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium fluoride, and 0.01% mmol of catalyst (compound 4) were added sequentially. Then, 1.2 mmol of tributylphenylene and 1 mL of dioxane were added, and the mixture was stirred at 100 °C for 6 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0191] Example 21

[0192] Compound 1 prepared in Example 1 was used in the Negishi coupling reaction:

[0193] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 1) were added sequentially. Then, 1.2 mmol of phenyl zinc chloride and 1 mL of tetrahydrofuran were added, and the mixture was stirred at 60 °C for 6 h. The product was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0194] Example 22

[0195] Compound 2 prepared in Example 2 was used in the Negishi coupling reaction:

[0196] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 2) were added sequentially. Then, 1.2 mmol of phenyl zinc chloride and 1 mL of tetrahydrofuran were added, and the mixture was stirred at 60 °C for 6 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0197] Example 23

[0198] Compound 3, prepared in Example 3, was used in the Negishi coupling reaction:

[0199] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 3) were added sequentially. Then, 1.2 mmol of phenyl zinc chloride and 1 mL of tetrahydrofuran were added, and the mixture was stirred at 60 °C for 6 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0200] Example 24

[0201] Compound 4, prepared in Example 4, was used in the Negishi coupling reaction:

[0202] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (compound 4) were added sequentially. Then, 1.2 mmol of phenyl zinc chloride and 1 mL of tetrahydrofuran were added, and the mixture was stirred at 60 °C for 6 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0203] Comparative Example 1

[0204] Using commercial ref-1 catalysts in the Suzuki coupling reaction:

[0205] In a Schlenk tube equipped with a magnetic stir bar, 1.5 mmol of phenylboronic acid, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (ref-1) were added sequentially. Then, 1.0 mmol of p-methoxybromobenzene and 1 mL of isopropanol were added, and the mixture was stirred at 80 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0206] The ref-1 catalyst is selected from palladium-based commercial catalysts such as tetra(triphenylphosphine)palladium, palladium acetate, or palladium dichloride·1,1'-bis(diphenylphosphine)ferrocene.

[0207] Comparative Example 2

[0208] Using commercial ref-2 catalysts in the Hartwig-Buchwald coupling reaction:

[0209] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.1 mmol of potassium tert-butoxide, and 0.01% mmol of catalyst (ref-2) were added sequentially. Then, 1.2 mmol of diphenylamine and 1 mL of toluene were added, and the mixture was stirred at 100 °C for 2 h. The solution was then dissolved in dichloromethane and stirred into alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 2:1) to obtain a colorless product. The yield was calculated after weighing.

[0210] The ref-2 catalyst is selected from palladium-based commercial catalysts such as di(dibenzylideneacetone)palladium or palladium acetate.

[0211] Comparative Example 3

[0212] Using commercial ref-3 catalysts in Heck coupling reactions:

[0213] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-bromobenzoic acid, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (ref-3) were added sequentially. Then, 1.2 mmol of acrylic acid and 1 mL of xylene were added, and the mixture was stirred at 120 °C for 2 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0214] The ref-3 catalyst is selected from palladium-based commercial catalysts such as palladium acetate, tetra(triphenylphosphine)palladium, or palladium dichloride·1,1'-bis(diphenylphosphine)ferrocene.

[0215] Comparative Example 4

[0216] Using commercial ref-4 catalysts for Still coupling reactions:

[0217] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium fluoride, and 0.01% mmol of catalyst (ref-4) were added sequentially. Then, 1.2 mmol of tributylphenylene and 1 mL of dioxane were added, and the mixture was stirred at 100 °C for 6 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0218] The ref-4 catalyst is selected from palladium-based commercial catalysts such as tetra(triphenylphosphine)palladium, dichlorodi(triphenylphosphine)palladium, or tri(dibenzylideneacetone)dipalladium.

[0219] Comparative Example 5

[0220] Using commercial ref-5 catalysts in the Negishi coupling reaction:

[0221] In a Schlenk tube equipped with a magnetic stir bar, 1.0 mmol of p-methoxybromobenzene, 1.2 mmol of potassium carbonate, and 0.01% mmol of catalyst (ref-5) were added sequentially. Then, 1.2 mmol of phenyl zinc chloride and 1 mL of tetrahydrofuran were added, and the mixture was stirred at 60 °C for 6 h. The solution was then dissolved in dichloromethane and mixed with alumina. Column chromatography was performed (eluent: dichloromethane / petroleum ether = 4:1) to obtain a colorless product. The yield was calculated after weighing.

[0222] The ref-5 catalyst is selected from palladium-based commercial catalysts such as tetra(triphenylphosphine)palladium, palladium acetate, or palladium dichloride·1,1'-bis(diphenylphosphine)ferrocene.

[0223] Furthermore, the general reaction formulas for the Suzuki coupling reactions in Examples 5 to 8 and Comparative Example 1 of this application are as follows:

[0224]

[0225] Furthermore, the general reaction formulas for the Hartwig-Buchwald coupling reactions of Examples 9 to 12 and Comparative Example 2 of this application are as follows:

[0226]

[0227] Furthermore, the general reaction formulas for the Heck coupling reactions in Examples 13 to 16 and Comparative Example 3 of this application are as follows:

[0228]

[0229] Furthermore, the general reaction formulas for the Still coupling reactions of Examples 17 to 20 and Comparative Example 4 of this application are as follows:

[0230]

[0231] Furthermore, the general reaction formulas for the Negishi coupling reactions in Examples 21 to 24 and Comparative Example 5 of this application are as follows:

[0232]

[0233] Performance testing

[0234] Yields: The yields of the Suzuki coupling reaction in Examples 5 to 8 and Comparative Example 1, the Hartwig-Buchwald coupling reaction in Examples 9 to 12 and Comparative Example 2, the Heck coupling reaction in Examples 13 to 16 and Comparative Example 3, the Still coupling reaction in Examples 17 to 20 and Comparative Example 4, and the Negishi coupling reaction in Examples 21 to 24 and Comparative Example 5 were tested. The test results are shown in Tables 1 to 5.

[0235] The experimental data and analysis are as follows:

[0236] Table 1 Suzuki Coupling Reactions

[0237]

[0238] As shown in Table 1, the heterocyclic tripterene mononuclear rhodium complexes (Examples 5 to 8) prepared in this application, compared with Comparative Example 1, exhibit improved catalytic efficiency due to the presence of sterically hindered tripterene groups that stabilize intermediates in the catalytic cycle. The Suzuki catalytic reaction can be achieved with a very high yield using only 0.01% of the amount of catalyst. In industrial production, the amount of catalyst used has a significant impact on raw material cost control and the ease of post-processing, offering a substantial advantage in cost control that the comparative example cannot achieve. Furthermore, the phenanthroline structure in the molecular structure improves catalyst solubility, and the strong π-coordination between the phenanthroline and cyclopentadiene structures hinders attack on the active center, reducing the reactivity of the active intermediate and providing excellent stability. Therefore, high catalytic activity is achieved. As can be seen from the examples, the catalytic effect is better when X is chlorine than when X is bromine. The catalytic efficiency is also significantly improved when a cyano electron-withdrawing group is introduced into the tripterene structure.

[0239] Table 2 Hartwig-Buchwald Coupling Reactions

[0240]

[0241] As shown in Table 2, the heterocyclic tripterene mononuclear rhodium complexes (Examples 9 to 12) prepared in this application, compared with Comparative Example 2, exhibit improved catalytic efficiency due to the presence of sterically hindered tripterene groups that stabilize intermediates in the catalytic cycle. Hartwig-Buchwald catalytic reactions can be achieved in very high yields with only 0.01% of the amount used. In industrial production, the amount of catalyst used has a significant impact on raw material cost control and the ease of post-processing, offering a substantial advantage in cost control that the comparative example cannot achieve. Furthermore, the phenanthroline structure in the molecular structure improves catalyst solubility, and the strong π-coordination between the phenanthroline and cyclopentadiene structures hinders attack on the active center, reducing the reactivity of the active intermediate and providing excellent stability. Therefore, high catalytic activity is achieved. As can be seen from the examples, the catalytic effect is better when X is chlorine than when X is bromine. The introduction of cyano electron-withdrawing groups into the tripterene structure also significantly improves catalytic efficiency.

[0242] Table 3 Heck Coupling Reactions

[0243]

[0244] As shown in Table 3, the heterocyclic tripterene mononuclear rhodium complexes (Examples 13 to 16) prepared in this application, compared with Comparative Example 3, have improved catalytic efficiency due to the presence of large sterically hindered tripterene groups that can stabilize intermediates in the catalytic cycle. The Heck catalytic reaction can be achieved in very high yields with only 0.01% of the amount used. However, compared with the comparative example, the improvement effect of this catalyst is limited.

[0245] Table 4 Still coupling reaction

[0246]

[0247] As shown in Table 4, the heterocyclic tripterene mononuclear rhodium complexes (Examples 17 to 20) prepared in this application, compared with Comparative Example 4, exhibit improved catalytic efficiency due to the presence of sterically hindered tripterene groups that stabilize intermediates in the catalytic cycle. A very high yield of Still catalytic reaction can be achieved with only 0.01% of the catalyst dosage. In industrial production, the amount of catalyst used has a significant impact on raw material cost control and the ease of post-processing, offering a substantial advantage in cost control that the comparative example cannot achieve. Furthermore, the phenanthroline structure in the molecular structure improves catalyst solubility, and the strong π-coordination between the phenanthroline and cyclopentadiene structures hinders attack on the active center, reducing the reactivity of the active intermediate and providing excellent stability. Therefore, high catalytic activity is achieved. As can be seen from the examples, the catalytic effect is better when X is chlorine than when X is bromine. The introduction of cyano electron-withdrawing groups into the tripterene structure also significantly improves catalytic efficiency.

[0248] Table 5 Negishi Coupling Reactions

[0249]

[0250] As shown in Table 5, the heterocyclic tripterene mononuclear rhodium complexes (Examples 21 to 24) prepared in this application, compared with Comparative Example 5, exhibit improved catalytic efficiency due to the presence of sterically hindered tripterene groups that stabilize intermediates in the catalytic cycle. Negishi catalytic reactions can be achieved with very high yields using only 0.01% of the amount of catalyst. In industrial production, the amount of catalyst used significantly impacts raw material cost control and the ease of post-processing, offering a substantial advantage in cost control that the comparative example cannot achieve. Furthermore, the phenanthroline structure in the molecular structure improves catalyst solubility, and the strong π-coordination between the phenanthroline and cyclopentadiene structures hinders attack on the active center, reducing the reactivity of the active intermediate and providing excellent stability. Therefore, high catalytic activity is achieved. As can be seen from the examples, the catalytic effect is better when X is chlorine than when X is bromine. The introduction of cyano electron-withdrawing groups into the tripterene structure also significantly improves catalytic efficiency.

[0251] In summary, the heterocyclic triptene mononuclear rhodium complex prepared in this application exhibits superior catalytic performance compared to conventional catalysts. It also demonstrates excellent applicability to various substituents and significantly reduces catalyst dosage, requiring only 0.01% of the catalyst to ensure catalytic reaction. This makes it suitable for a wide range of metal-catalyzed reactions. The synthesis method is simple, yields high efficiency, and has significant potential for widespread application—achievements unattainable with conventional metal catalysts. Such results are beyond the expectations of those skilled in the art.

[0252] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A heterocyclic triterpenoid mononuclear rhodium complex, characterized in that, Its structural formula I is as follows: ， In the structural formula I, R1 is selected from any one of -H, -F, -CN, -CF3, substituted or unsubstituted alkyl groups with 1 to 5 carbon atoms, fused phenyl groups, or fused cyclopentyl groups; R2, R3, and R4 are each independently selected from any one of the following: -H, -D, -Cl, -F, -CN, -CD3, -CF3, -OCF3, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted alkoxy groups with 1 to 10 carbon atoms, straight-chain substituted or unsubstituted olefin groups with 2 to 10 carbon atoms, fluorinated substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, fluorinated substituted or unsubstituted alkoxy groups with 1 to 10 carbon atoms, fluorinated substituted or unsubstituted olefin groups with 2 to 10 carbon atoms, substituted or unsubstituted aryl groups with 5 to 20 carbon atoms, substituted or unsubstituted heteroaryl groups with 5 to 20 carbon atoms, substituted or unsubstituted fused-ring aryl groups with 5 to 20 carbon atoms, or substituted or unsubstituted heterofused-ring aryl groups with 5 to 20 carbon atoms. R5 is selected from any one of -H, -D, -Cl, -F, -CN, -CD3, -CF3, -CH3, or a benzene ring; X represents Cl, Br, and I atoms.

2. The method for preparing the heterocyclic triterpenoid mononuclear rhodium complex according to claim 1, characterized in that, Includes the following steps: (1) Aromatic hydrocarbons and their derivatives are mixed with ethylene acetate, and then subjected to addition reaction and purification to obtain hydroxyl compounds; (2) The hydroxyl compound is mixed with p-benzoquinone, and then subjected to catalytic oxidation and purification to obtain a carbonyl compound; (3) The carbonyl compound is mixed with 8-amino-7-aldehyde quinoline or a substituted product of 8-amino-7-aldehyde quinoline, and the mixture is subjected to condensation reaction and purification to obtain an intermediate ligand; (4) The intermediate ligand is mixed with the ligand precursor, rhodium halide, and sodium trifluoromethanesulfonate, and then coordinated and purified to obtain the heterocyclic triptene mononuclear rhodium complex.

3. The method according to claim 2, characterized in that, The reaction conditions in step (1) satisfy at least one of the following conditions (a) to (c): (a) The aromatic hydrocarbons and their derivatives are selected from anthracene, tetraphenylene, or 2,3-dicyanoanthracene; (b) The addition reaction is carried out in a reaction system of potassium tert-butoxide and tetrahydrofuran; (c) The purification includes alumina column chromatography and dichloromethane elution.

4. The method according to claim 2, characterized in that, The reaction conditions in step (2) satisfy at least one of the following conditions (d) to (e): (d) The catalytic oxidation reaction is carried out in a reaction system of aluminum tritert-butoxy and tetrahydrofuran; (e) The purification process includes alumina column chromatography followed by elution with a mixture of dichloromethane and petroleum ether.

5. The method according to claim 2, characterized in that, The reaction conditions in step (3) satisfy at least one of the following conditions (f) to (h): (f) The substituents of the substituted 8-amino-7-aldehyde quinoline are halogen elements; (g) The condensation reaction is carried out in a reaction system of potassium tert-butoxide and tert-butanol; (h) The purification process includes alumina column chromatography followed by elution with a mixture of dichloromethane and ethyl acetate.

6. The method according to claim 2, characterized in that, In step (4), the ligand precursor is selected from cyclopentadiene, pentamethylcyclopentadiene, or 1-trifluoromethyl-pentamethylcyclopentadiene.

7. The method according to claim 2, characterized in that, In step (4), the rhodium halide is selected from rhodium trichloride, rhodium tribromide or rhodium triiodide.

8. The method according to claim 2, characterized in that, In step (4), the coordination is carried out in a tetrahydrofuran solution of n-butyllithium.

9. The application of the heterocyclic triterpenoid mononuclear rhodium complex according to claim 1, characterized in that, The heterocyclic triterpenoid mononuclear rhodium complex was used in a catalyst.

10. The application according to claim 9, characterized in that, The catalysts are used in the Suzuki reaction, Buchwald-Hartwig reaction, Heck reaction, Still reaction, and Negishi reaction.

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