Ionic pair-type homo- / heteronuclear bimetallic complexes, simple synthesis method thereof and application

Abstract

The present invention belongs to the technical field of the synthesis of metal-organic complexes, and particularly relates to an ion-pair type homo- / hetero-nuclear bimetallic complex, a simple synthesis method thereof and an application thereof. The bimetallic complex is prepared by a metathesis reaction between a quaternary ammonium cationic monoazaheterocyclic carbene palladium complex and a sulfonic acid anionic monoazaheterocyclic carbene palladium / platinum / copper complex. In the Sonogashira coupling reaction, the complexes of the present invention exhibit more excellent catalytic activity compared with the individual complexes.

Description

Technical Field

[0001] The present invention belongs to the technical field of the synthesis of metal-organic complexes, and particularly relates to an ion-pair type homo- / hetero-nuclear bimetallic complex, a simple synthesis method thereof and an application thereof. Background Art

[0002] The chemical easy modification property of N-heterocyclic carbene (NHC) ligands makes them one of the most widely used ligands in organometallic chemistry. In recent years, in the field of organometallic chemistry, the synthesis and application of bimetallic complexes have attracted great interest of scientists.

[0003] Compared with monometallic complexes, the electron communication in bimetallic complexes not only generates physical properties such as luminescence, fluorescence, nonlinear optical activity, redox properties, and charge or energy transfer, but also promotes many chemical reactions. Among them, the most widely studied is the application of bimetallic complexes in catalytic reactions, such as cross-coupling, transfer hydrogenation, ammonia synthesis, etc.

[0004] In 2017, the Choudhury group prepared a palladium bimetallic complex, which showed high catalytic activity in both catalytic aromatic C-H acetoxylation and directed halogenation reactions [Journal of Molecular Catalysis A: Chemical, 2017, 426, 451-457]. In 2019, the Maity group prepared a palladium / iridium bimetallic complex and successfully catalyzed the tandem organic reaction of C-C coupling and transfer hydrogenation [European Journal of Inorganic Chemistry, 2019, 2019(13): 1810-1815]. The excellent performance of bimetallic complexes in cooperative or tandem catalytic reactions has attracted much attention. However, existing bimetallic complexes, especially heteronuclear bimetallic complexes, require the design of specific ligands, and multiple ligand sites in the ligands should be able to selectively coordinate different metal centers. Therefore, the synthesis steps of the ligands in such complexes are relatively complex, and by-products such as only mononuclear coordination and homonuclear bicoordination are likely to be generated during the coordination reaction, resulting in a reduction in the yield of the target product, thereby limiting the progress of related research. Summary of the Invention

[0005] In order to study a simple synthesis method of a bimetallic complex, the present invention establishes a method for preparing a bimetallic complex by a metathesis reaction of a quaternary ammonium cationic mono-N-heterocyclic carbene palladium complex and a sulfonic acid anionic mono-N-heterocyclic carbene palladium / platinum / copper complex.

[0006] The synthesis method of the quaternary ammonium cationic mono - N - heterocyclic carbene palladium complex of the present invention is as follows: First, react the bromopropyl - modified N - heterocyclic precursor salt with 0.6 equivalent of silver oxide in dichloromethane at room temperature for 3 hours. Then, drop the mixed solution into an acetonitrile solution of 1 equivalent of [PdBr2(CH3CN)2] and react at room temperature for 20 hours to obtain the bromopropyl - modified dimeric complex 1. Next, use complex 1 and 40 equivalents of diethylamine as raw materials, use chloroform as a solvent and react at 70 °C for 24 hours to obtain complex 2. Then, dissolve complex 2 and 20 equivalents of bromoethane in acetonitrile and react at 80 °C for 12 hours to obtain complex 3. Finally, use the dimeric palladium complex 3 and 2.1 equivalents of pyridine as raw materials, and react in a mixed solvent of dichloromethane and methanol (V / V: 5 / 1) at room temperature for 2 hours to synthesize the quaternary ammonium cationic mono - N - heterocyclic carbene palladium complex 4. The synthesis route is as follows:

[0007]

[0008] The synthesis method of the sulfonic acid anionic mono - N - heterocyclic carbene palladium complex 5 is as follows: React the sulfonic acid propyl - modified N - heterocyclic precursor salt with 0.5 equivalent of silver oxide and 1 equivalent of potassium halide in dichloromethane / methanol / water for 3 hours, then filter it into an acetonitrile solution of 0.5 equivalent of [PdBr2(CH3CN)2] and react for 20 hours. Then, collect the liquid phase and react with 1.05 equivalents of pyridine at room temperature for 2 hours to obtain the anionic mono - N - heterocyclic carbene palladium complex.

[0009] The synthesis method of the sulfonic acid anionic mono - N - heterocyclic carbene platinum complex 6 is as follows: React the sulfonic acid propyl - modified N - heterocyclic precursor salt with 1 equivalent of platinum bromide and 10 equivalents of potassium carbonate in pyridine, and react at 100 °C for 12 hours under a nitrogen atmosphere to obtain the anionic mono - N - heterocyclic carbene platinum complex.

[0010] The synthesis method of the sulfonic acid anionic mono - N - heterocyclic carbene copper complex 7 is as follows: Use the sulfonic acid propyl - modified N - heterocyclic precursor salt, 0.8 equivalent of cuprous oxide and 1 equivalent of potassium bromide as raw materials, and stir at room temperature in a mixed solvent of dichloromethane, methanol and water for 24 hours to obtain the anionic mono - N - heterocyclic carbene copper complex. The synthesis route is as follows:

[0011]

[0012] The synthesis method of the ion - pair - type N - heterocyclic carbene homo(hetero) - bimetallic complex is as follows: Mix the aqueous solutions of the cationic mono - N - heterocyclic carbene palladium complex 4 and the anionic mono - N - heterocyclic carbene palladium / platinum / copper complexes 5 - 7 in three ways of 4 + 5, 4 + 6, and 4 + 7 at a 1:1 equivalent ratio, and react at room temperature for 3 - 24 hours to obtain the ion - pair - type homo(hetero) - nuclear bimetallic complexes 8 - 10. The synthesis route is as follows:

[0013]

[0014] Among them, M is metal Pd, Pt, Cu, and L is pyridine, Br.

[0015] After successfully obtaining and fully characterizing the above complex, the complex was used to catalyze the Sonogashira coupling reaction.

[0016]

[0017] R = CN, CH3, CH3CO; X = Br, I

[0018] The experimental results show that compared with its cationic and anionic N-heterocyclic carbene complex precursors, the ion pair type bimetallic complexes of the present invention all show higher catalytic activity in the Sonogashira coupling reaction. Among them, the Pd / Cu bimetallic catalyst has the highest activity, and the catalyst dosage is only 0.1 mol%.

[0019] Advantages and technical effects of the present invention:

[0020] By carrying out a metathesis reaction between a quaternary ammonium cationic mono-N-heterocyclic carbene palladium complex and a sulfonic acid anionic mono-N-heterocyclic carbene complex, the present invention first discloses a simple method for synthesizing homo (hetero) nuclear bimetallic complexes. The obtained Pd / Cu complexes show excellent catalytic activity in the Sonogashira coupling reaction with different substrates. Specific embodiments

[0021] The following further details the present invention in combination with embodiments. Among them, the structural formula of the quaternary ammonium propyl-modified dimeric palladium complex is

[0022] The structural formula of the sulfonic acid propyl-modified N-heterocyclic precursor salt is:

[0023] Example 1

[0024]

[0025] (1) Synthesis of quaternary ammonium cationic mono-N-heterocyclic carbene palladium complex 4

[0026] First, the bromopropyl-modified azacycle precursor salt was reacted with 0.6 equivalent of silver oxide in dichloromethane at room temperature for 3 hours. The resulting mixture was added dropwise to an acetonitrile solution of 1 equivalent of [PdBr2(CH3CN)2] and reacted at room temperature for 20 hours to obtain the bromopropyl-modified dimer complex 1. Then, using complex 1 and 40 equivalents of diethylamine as raw materials, the reaction was carried out in chloroform as a solvent at 70 °C for 24 hours to obtain complex 2. Subsequently, complex 2 and 20 equivalents of bromoethane were dissolved in acetonitrile and reacted at 80 °C for 12 hours to obtain complex 3.

[0027] A mixture of the dimer complex 3 (65 mg, 0.05 mmol), CH2Cl2 (10 mL), and pyridine (9 μL, 0.11 mmol) was stirred at room temperature for 2 hours. The solvent was dried under reduced pressure, and the residue was washed with Et2O (5 mL × 3) to obtain complex 4.

[0028] 4: Yellow solid (68 mg, 0.09 mmol, 94%). 1 H NMR (300 MHz, CDCl3): δ 8.99 (d, 2H, 3 J H-H = 5 Hz, Py-H), 7.88 (d, 1H, 3 J H-H = 2 Hz, Py-H), 7.76 (t, 1H, 3 J H-H = 8 Hz, Ar-H), 7.48 - 7.45 (m, 2H, Py-H), 7.37 - 7.33 (m, 5H, Ar-H), 6.74 (d, 1H, 3 J H-H = 2 Hz, Ar-H), 5.75 (s, 2H, NCH2Ph), 4.84 - 4.81 (t, 2H, 3 J H-H = 7 Hz, NCH2), 3.69 - 3.63 (m, 2H, CH2CH2N + ), 3.46 - 3.39 (q, 6H, 3 J H-H = 7 Hz, N + CH2CH3), 2.76 (br-s, 2H, CH2), 1.31 - 1.27 (t, 9H, 3 J H-H = 7 Hz, CH3). 13 C{ 1 H}NMR (75 MHz, CDCl3): δ 152.5 (C Py ), 147.9 (C carbene ), 138.2, 135.0 (C Py),129.1,128.9,128.6,124.8,124.3,122.1(Ar-C),55.0,53.5(CH2N + ),47.5(NCH2),23.4(CH2),8.2(CH3).Anal.Calcd.forC 24 H 35 Br3N4Pd:C 39.72,H 4.86,N 7.72;found:C 39.69,H 4.96,N 7.67.MS-ESI(m / z):[M–Br–Py] + calcd for C 19 H 30 Br2N3Pd + 566,found 566.

[0029] (2) Synthesis of sulfonate anion type monoazacyclic carbene palladium complex 5

[0030] Take PdBr2 (27 mg, 0.10 mmol) and CH3CN (8 mL) in a 50 mL round-bottom flask, heat and reflux at 80 °C for 1 hour to obtain an acetonitrile solution of [PdBr2(CH3CN)2]. At the same time, dissolve the imidazole precursor salt substituted with propyl sulfonate (28 mg, 0.10 mmol), KBr (12 mg, 0.10 mmol), and Ag2O (14 mg, 0.06 mmol) in a mixed solvent of DCM (10 mL), MeOH (2 mL), and 3 drops of H2O, and stir in the dark at room temperature for 3 hours to obtain Ag-NHC. Under light-shielded conditions, filter Ag-NHC into the [PdBr2(CH3CN)2] solution and react at room temperature for 20 hours. Filter the suspension and collect the liquid phase, then add Et2O to this filtrate to obtain a brown suspension. Collect the precipitate and dissolve it in DCM (5 mL). Add pyridine (9 μL, 0.07 mmol), stir at room temperature for 2 hours, remove the solvent by vacuum distillation to obtain a gray solid. Finally, wash away the excess pyridine with Et2O (5 mL × 3) to obtain the product.

[0031] 5: Yellow solid (38 mg, 0.06 mmol, 58%). 1 H NMR (400 MHz, DMSO-d6): δ8.87 (d, 2H, 3 J H-H =5Hz, Py-H), 7.97 - 7.94 (t, 1H, 3 J H-H= 7 Hz, Py-H), 7.57 - 7.50 (m, 4H, Ar-H), 7.46 (s, 1H, Ar-H), 7.39 - 7.33 (m, 3H, Ar-H), 7.19 (s, 1H, Ar-H), 5.71 (s, 2H, NCH2Ph), 4.59 - 4.56 (t, 2H, 3 J H-H = 6 Hz, NCH2), 2.61 - 2.57 (t, 2H, 3 J H-H = 7 Hz, SCH2), 2.39 - 2.36 (m, 2H, CH2). 13 C{ 1 H} NMR (100 MHz, DMSO-d6): δ 152.1 (C Py ), 146.9 (C carbene ), 138.6, 136.3, 128.7, 128.5, 127.9, 124.9, 123.5, 122.1 (Ar-C), 53.7 (NCH2Ph), 49.4 (NCH2), 48.3 (SCH2), 26.1 (CH2). Anal. Calcd. for C 18 H 20 Br2KN3O3PdS: C 32.57, H 3.04, N 6.33; found: C 32.47, H 3.22, N 6.37. MS-ESI (m / z): [M + H] + calcd for C 18 H 21 Br2KN3O3PdS + 664, found 664.

[0032] (3) Synthesis of ion pair type Pd / Pd bimetallic complex 8

[0033] Complex 5 (67 mg, 0.10 mmol) and complex 4 (73 mg, 0.10 mmol) were mixed and stirred in H2O (10 ml) for 3 h. The resulting suspension was filtered through a funnel, and the residue was washed with H2O (5 mL × 3) to obtain the product.

[0034] 8: Yellow solid (108 mg, 0.09 mmol, 85%). 1 H NMR (300 MHz, CDCl3): δ

[0035] 8.99 - 8.96 (m, 4H, Py - H), 7.77 - 7.68 (m, 3H, Py - H), 7.50 - 7.45 (m, 4H, Py - H and Ar - H), 7.37 - 7.27 (m, 10H, Ar - H), 7.20 (d, 1H, 3 J H-H = 2Hz, Ar - H), 6.74 (d, 1H, 3 J H-H = 2Hz, Ar - H), 6.66 (d, 1H, 3 J H-H = 2Hz, Ar - H), 5.73 (s, 4H, NCH2Ph), 4.75 - 4.71 (t, 4H, 3 J H-H = 7Hz, NCH2), 3.56 - 3.50 (m, 2H, CH2CH2N + ), 3.35 - 3.28 (t, 6H, 3 J H-H = 14Hz, 7Hz, N + CH2CH3), 2.98 - 2.94 (t, 2H, 3 J H-H = 7Hz, CH2S), 2.68 - 2.62 (m, 4H, CH2), 1.24 - 1.19 (t, 9H, 3 J H-H = 7Hz, CH3). 13 C{ 1 H}NMR(75MHz, CDCl3): δ152.7, 152.6 (C Py ), 147.7, 147.3 (C carbene ), 138.2, 137.9 (C Py ), 135.5, 135.1 (C Py ), 129.2, 129.1, 129.0, 128.9, 128.7, 128.5, 124.8, 124.6, 124.4, 123.6, 122.3, 121.3 (Ar - C), 55.1, 55.0 (NCH2Ph), 53.2 (CH2N + , 1×coincident), 49.8, 48.4 (NCH2), 47.5 (CH2S), 26.3, 23.2 (CH2), 7.9 (CH3). Anal. Calcd. for C 42 H 55Br4N7O3Pd2S: C 39.71, H 4.36, N 7.72; found: C 39.43, H 4.73, N 7.98. MS-ESI (m / z): [M–Py] + calcd for C 19 H 30 Br2N3Pd + 566, found 566; [M–Py] - calcd for C 13 H 15 Br2N2O3PdS - 545, found 545.

[0036] Example 2

[0037]

[0038] (1) Synthesis of sulfonate anion type monoazacyclic carbene platinum complex 6

[0039] Add the imidazole precursor salt substituted with propyl sulfonate (42 mg, 0.15 mmol), PtBr2 (53 mg, 0.15 mmol), K2CO3 (207 mg, 1.50 mmol) and 0.5 mL of pyridine into a 10 mL Schlenk tube. Stir the mixture at 100 °C overnight under N2 atmosphere. Then, remove the excess pyridine under reduced pressure, and dissolve the remaining solid in CH2Cl2. Remove the insoluble matter by normal pressure filtration, collect the CH2Cl2 phase and purify it by silica gel column chromatography (eluent: methanol / dichloromethane = 1 / 20, V / V) to obtain the product.

[0040] 6: Yellow solid (20 mg, 0.03 mmol, 18%). 1 H NMR (400 MHz, CDCl3): δ 8.87 - 8.86 (d, 2H, 3 J H-H = 5 Hz, Py-H), 7.54 - 7.51 (m, 1H, Py-H), 7.44 - 7.42 (m, 2H, Ar-H), 7.25 (s, 1H, Ar-H), 7.23 (m, 2H, Ar-H), 7.19 - 7.15 (m, 2H, Ar-H), 7.02 (s, 1H, Ar-H), 6.55 (d, 1H, 3 J H-H = 2 Hz, Ar-H), 5.63 (s, 2H, NCH2Ph), 4.52 (br-s, 2H, NCH2), 3.01 (br-s, 2H, SCH2), 2.48 (br-s, 2H, CH2).

[0041] (2) Synthesis of ionic pair type Pd / Pt bimetallic complex 9

[0042] Complex 6 (15 mg, 0.02 mmol) and complex 4 (prepared in the same way as in Example 1) (15 mg, 0.02 mmol) were mixed and stirred in H2O (3 ml) for 3 hours. The resulting suspension was filtered through a funnel, and the residue was washed with H2O (5 mL×3) to obtain the product.

[0043] 9: Yellow solid product (25 mg, 0.02 mmol, 92%). 1 H NMR (400 MHz, CDCl3): δ8.99 - 8.98 (m, 4H, Py - H), 7.75 - 7.68 (m, 3H, Py - H), 7.47 - 7.45 (m, 4H, Py - H and Ar - H), 7.36 - 7.30 (m, 10H, Ar - H), 7.13 (d, 1H, 3 J H-H = 2 Hz, Ar - H), 6.74 (d, 1H, 3 J H-H = 2 Hz, Ar - H), 6.61 (d, 1H, 3 J H-H = 2 Hz, Ar - H), 5.77 (s, 2H, NCH2Ph), 5.74 (s, 2H, NCH2Ph), 4.76 - 4.72 (m, 4H, NCH2), 3.57 (br - s, 2H, CH2CH2N + ), 3.34 (m, 6H, N + CH2CH3), 2.99 (t, 2H, 3 J H-H = 7 Hz, CH2S), 2.62 (m, 4H, CH2), 1.23 (t, 9H, 3 J H-H = 7 Hz, CH3).

[0044] Example 3

[0045]

[0046] (1) Synthesis of sulfonic acid anion type monocyclic carbene copper complex 7

[0047] Dissolve the sulfopropyl-substituted imidazole precursor salt (140 mg, 0.5 mmol), KBr (60 mg, 0.5 mmol), and Cu2O (57 mg, 0.4 mmol) in a mixed solution of 5 drops of H2O, CH2Cl2 (6 mL), and CH3OH (2 mL) to obtain a red turbid solution, and stir at room temperature for 24 hours. After the reaction is completed, filter off the insoluble matter through a funnel, collect the liquid phase, and dry the solvent to obtain the product.

[0048] 7: Pale green solid (169 mg, 0.37 mmol, 73%). 1 H NMR (300 MHz, D2O): δ

[0049] 7.52 - 7.51 (d, 1H, 3 J H-H = 2 Hz, Ar-H), 7.46 - 7.43 (m, 4H, Ar-H), 7.39 - 7.36 (m, 2H, Ar-H), 5.36 (s, 2H, NCH2Ph), 4.33 - 4.29 (t, 2H, 3 J H-H = 7 Hz, NCH2), 2.89 - 2.84 (t, 2H, 3 J H-H = 7 Hz, SCH2), 2.32 - 2.22 (m, 2H, CH2). 13 C{ 1 H}NMR (100 MHz, D2O): δ 133.4, 129.3, 129.2, 128.6, 122.6, 122.5 (Ar-C), 52.9 (NCH2Ph), 47.9 (NCH2), 47.2 (SCH2), 25.1 (CH2). Extend the test time, and no carbene carbon signal is still observed in the 13 13C NMR spectrum.

[0050] (2) Synthesis of the ion pair type Pd / Cu bimetallic complex 10

[0051] Add complex 7 (9 mg, 0.02 mmol), complex 4 (the specific preparation method is the same as in Example 1) (15 mg, 0.02 mmol), and H2O (3 mL) to a 25 mL round-bottom flask, and stir at room temperature for 24 hours. Dry the solvent of the obtained suspension, and dissolve the product with a mixed solvent of CH2Cl2 / CH3OH.

[0052] 10: Obtain a yellow solid (19 mg, 0.02 mmol, 90%). 11H NMR (300 MHz, CD3OD): δ 8.96 - 8.94 (m, 2H, Py - H), 7.92 (s, 1H, Ar - H), 7.69 (d, 1H, 3 J H-H = 2 Hz, Ar - H), 7.62 - 7.57 (m, 3H, Ar - H), 7.48 - 7.43 (m, 7H, Ar - H), 7.38 - 7.36 (m, 4H, Ar - H), 7.09 (d, 1H, 3 J H-H = 2 Hz, Ar - H), 5.77 (s, 2H, NCH2Ph), 5.42 (s, 2H, NCH2Ph), 4.73 - 4.68 (t, 2H, 3 J H-H = 7 Hz, NCH2), 4.45 - 4.39 (t, 2H, 3 J H-H = 7 Hz, NCH2), 3.53 - 3.47 (m, 2H, CH2CH2N + ), 3.39 - 3.34 (m, 6H, N + CH2CH3), 2.80 - 2.78 (t, 2H, 3 J H-H = 7 Hz, CH2S), 2.60 - 2.50 (m, 2H, CH2), 2.36 - 2.27 (m, 2H, CH2), 1.29 - 1.25 (t, 9H, 3 J H-H = 7 Hz, CH3).

[0053] Example 4 Catalytic Application of the Complex of the Present Invention

[0054] In an air atmosphere, an aryl halide (0.20 mmol), a catalyst (4, 7 - 10), phenylacetylene (0.20 mmol, 20 mg), Cs2CO3 (0.40 mmol, 141 mg), dioxane (600 μL), and internal standard dodecane (0.20 mmol) were added to a reaction flask. After the reaction was completed, dichloromethane (2 mL) and H2O (2 mL) were added for extraction. The organic phase was dried over anhydrous sodium sulfate, and then 3 drops of the crude product were taken and diluted to 2 mL with dichloromethane for quantitative analysis by gas chromatography.

[0055] At a catalytic dosage of 0.1 mol%, the palladium complex 4 showed certain catalytic activity, while the catalytic result of the copper complex 7 was not satisfactory. After the formation of ion - pair heterobimetallic complexes 8 - 10 through a simple metathesis reaction, their catalytic effects increased significantly. Among them, the palladium / copper bimetallic complex showed the best synergistic effect (Table 1).

[0056] Table 1a

[0057]

[0058]

[0059] a Reaction conditions: aryl halide (0.20 mmol), phenylacetylene (0.20 mmol), cesium carbonate (0.40 mmol), catalyst (0.1 mol%), dioxane (600 μL), air atmosphere, 100 °C. b The GC yield, using dodecane as the internal standard, is the average of two parallel reactions.

Claims

1. An ion pair type homo- / hetero-nuclear bimetallic complex, characterized in that: The complex contains a quaternary ammonium-modified cationic monoazacyclic carbene complex unit and a sulfonate-modified anionic monoazacyclic carbene complex unit; the specific structure of this ion-pair type homo- / hetero-nuclear bimetallic complex is as follows: Among them, M is metal Pd, Pt, Cu, and L is pyridine, Br.

2. A method for synthesizing the ion pair type homo- / hetero-nuclear bimetallic complex according to claim 1, characterized in that: The steps of the synthesis method are as follows: (1) Synthesis of quaternary ammonium cationic monoazacyclic carbene palladium complex: Using the quaternary ammonium propyl-modified dimeric palladium complex and pyridine with an equivalent ratio of 1:2.1 as raw materials, reacting at room temperature for 2 hours in a mixed solvent of dichloromethane and methanol to synthesize the quaternary ammonium cationic monoazacyclic carbene palladium complex; The structural formula of the quaternary ammonium propyl-modified dimeric palladium complex is (2) Synthesis of sulfonate anionic monoazacyclic carbene palladium / platinum / copper complex: The synthesis method of the sulfonate anionic monoazacyclic carbene palladium complex is as follows: reacting the sulfonic acid propyl-modified azacyclic precursor salt with 0.5 equivalent of silver oxide and 1 equivalent of potassium halide in a mixed solvent of dichloromethane, methanol and water at room temperature for 3 hours, then filtering into an acetonitrile solution of 0.5 equivalent of [PdBr2(CH3CN)2] and reacting at room temperature for 20 hours, and collecting the liquid phase and reacting with 1.05 equivalents of pyridine at room temperature for 2 hours to obtain the anionic monoazacyclic carbene palladium complex; The synthesis method of the sulfonate anionic monoazacyclic carbene platinum complex is as follows: reacting the sulfonic acid propyl-modified azacyclic precursor salt with 1 equivalent of platinum bromide and 10 equivalents of potassium carbonate in pyridine at 100 °C for 12 hours in a nitrogen atmosphere to obtain the anionic monoazacyclic carbene platinum complex; The synthesis method of the sulfonate anionic monoazacyclic carbene copper complex is as follows: using the sulfonic acid propyl-modified azacyclic precursor salt, 0.8 equivalent of cuprous oxide and 1 equivalent of potassium bromide as raw materials, stirring at room temperature for 24 hours in a mixed solvent of dichloromethane, methanol and water to obtain the anionic monoazacyclic carbene copper complex; The structural formula of the sulfonic acid propyl-modified azacyclic precursor salt is: (3) Synthesis of ion-pair type azacyclic carbene homo- / hetero-bimetallic complex Using water as the solvent, the cationic monoazacyclic carbene palladium complex and the anionic monoazacyclic carbene palladium / platinum / copper complex undergo a metathesis reaction in a 1:1 equivalent ratio to obtain the ion-pair type homo- / hetero-nuclear bimetallic complex.

3. Use of the ion pair type homo- / hetero-nuclear bimetallic complex according to claim 1, characterized in that, The said complex is used for catalyzing the Sonogashira coupling reaction.

Images