A compound, preparation method and application thereof

Abstract

The application relates to the technical field of catalysts, and discloses a compound, a preparation method and application of the compound, and the compound is (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II). The compound (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II) can be used in a green and environment-friendly hydrogen reduction process, has high catalytic efficiency, high catalytic yield and strong recyclability, the catalyst is not easy to be poisoned, and the catalyst cannot cause product dehalogenation to produce impurities, and the catalyst can be expected to be used in industrial production on a large scale.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalysts, and mainly relates to a compound and a preparation method and application thereof. BACKGROUND

[0002] When nitrobenzene derivatives are reduced to aniline, there are hydrazine hydrate reduction method, sulfide salt reduction method and metal reduction method, etc., and the solid wastes generated by the three reduction methods all contain a large amount of pollutants. For example, the “List of backward production process equipment for industrial solid waste producing serious environmental pollution” issued by the Ministry of Industry and Information Technology of the People's Republic of China No. 25 in 2021 clearly stipulates that the “iron powder reduction process for producing acetaminophen” process is limited to stop production. This process is to reduce p-nitrophenol with iron powder to produce p-aminophenol. The solid waste iron powder produced by this process contains a large amount of pollutants that cannot be treated, which seriously pollutes the environment. The use of hydrogenation reduction method can avoid the problem of generating a large amount of pollutants. The hydrogenation reduction method has the advantages of being green, non-polluting, non-solid waste, and easy to recycle catalyst, and is the recommended reduction process by the state. However, when reducing halogen-containing compounds by using the traditional platinum-carbon or palladium-carbon hydrogenation catalyst, catalyst poisoning occurs, which leads to slow reaction or even reaction failure. Therefore, it is urgent for relevant practitioners to develop advanced anti-poisoning hydrogenation catalysts for use in green and environmentally friendly hydrogenation processes.

[0003] Therefore, the prior art still needs to be improved and developed. SUMMARY

[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide a compound and a preparation method and application thereof. The compound is (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II), which is a platinum complex formed by using phenylpyridine derivatives, dimethyl sulfoxide and chloride ions as ligands, and hydrogen bonds and π-π stacking. It is a platinum catalyst that can effectively catalyze hydrogenation reaction, and aims to solve the problem of catalyst poisoning of existing platinum-carbon or palladium-carbon hydrogenation catalysts when reducing halogen-containing compounds by using hydrogenation reduction method.

[0005] The technical scheme of the present application is as follows:

[0006] A compound, wherein the compound is (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II), and the molecular structure formula is shown in formula (1):

[0007] Formula (1).

[0008] The compound, wherein a structural unit of the compound belongs to a monoclinic C2 / c (No. 15) group, and cell parameters are: a = 7.9405(8) Å, b = 18.0744(18) Å, c = 21.513(2) Å, α = 90.00°, β = 98.7810(10)°, γ = 90.00°.

[0009] A preparation method of the compound, comprising the following steps:

[0010] (1) suspending 5-nitro-2-phenylpyridine and potassium chloroplatinate in ethylene glycol monoethyl ether to obtain a suspension, and stirring the suspension under nitrogen protection;

[0011] (2) removing the ethylene glycol monoethyl ether by rotary evaporation, and then adding dimethyl sulfoxide and stirring;

[0012] (3) open and standing for volatilization to obtain orange-yellow block crystals, filtering and drying to constant weight to obtain the (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) platinum (II) chloride.

[0013] The preparation method of the compound (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) platinum (II) chloride has simple synthesis route and mild reaction conditions, and the finished product can be obtained by self-volatilization crystallization.

[0014] The preparation method of the compound, wherein in step (1), the molar ratio of the potassium chloroplatinate to the 5-nitro-2-phenylpyridine is 1: (2-5).

[0015] The preparation method of the compound, wherein in step (1), the weight ratio of the potassium chloroplatinate to the ethylene glycol monoethyl ether is 1: (40-100).

[0016] The preparation method of the compound, wherein the molar ratio of the potassium chloroplatinate to the dimethyl sulfoxide is 1: (500-1000).

[0017] The preparation method of the compound, wherein in step (1), the stirring temperature is 60-90°C, and the stirring time is 5-20 hours during the stirring of the suspension.

[0018] In step (2), the stirring temperature is 5-25°C, and the stirring time is 5-25 hours during the stirring.

[0019] The preparation method of the compound, wherein in step (3), the standing time is 5-25 days, and the standing temperature is 25-30°C.

[0020] In step (3), the drying process is carried out at a temperature range of 50-70℃.

[0021] Use of a compound as described above, wherein the compound is used as a catalyst for a hydrogenation reduction process.

[0022] Use of the compound, wherein the compound is used as a catalyst in a reaction of hydrogenation reduction of a nitrobenzene derivative into aniline.

[0023] Beneficial effects: In this application, the complex (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II) is synthesized for the first time with 5-nitro-2-phenylpyridine (5-NO2-ppy), dimethyl sulfoxide (DMSO) and chlorine (Cl) as ligands. The compound (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II) of this application can be used in green and environmentally friendly hydrogenation reduction process, with high catalytic efficiency, high catalytic yield, strong recyclability, catalyst not easy to be poisoned, and no impurities produced by dehalogenation of the product, which is expected to be used in large-scale industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The figure is a schematic diagram of the molecular structure of the compound of this application. DETAILED DESCRIPTION

[0025] The present application provides a compound, a preparation method and an application thereof. In order to make the purpose, technical scheme and effects of the present application more clear and explicit, the present application is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0026] Platinum-containing compounds are widely used in various fields of life and scientific research. In the field of medicine, oxaliplatin, calcium folinate, and fluorouracil form a combined drug regimen mFOLFOX6, which, in combination with Zolbetuximab (Zotatuximab), has a significant effect on the treatment of various cancers (Shitara K et al. The Lancet, 2023, 401(10389): 1655-1668). In the field of fuel cells, Xuetong (Chemical Communications, 2022, 85(08): 909-917) et al. reviewed the latest progress of various types of carbon-supported platinum-based catalysts used in fuel cells. In the field of catalysts, Chengcheng Li (ACS Catal. 2021, 11, 8716-8726) et al. used platinum-containing catalyst (P~P)Pt(PR2OH)X(OTf) to catalyze the synthesis of amide structure from nitrile group structure, with high efficiency and good yield. In the field of optics, Song Jintong (Angew. Chem. Int. Ed, 2023, 135, e20230201) et al. used binuclear platinum (II) complex to construct three-dimensional double-plane molecules, which can achieve 100% phosphorescent quantum yield, chiral self-selection and circularly polarized luminescence, etc.

[0027] In the present application, the compound provided by the present application is a platinum-containing compound, which is a platinum complex formed by phenylpyridine derivative, dimethyl sulfoxide and chloride ion as ligand, hydrogen bond and π-π bond stacking. It is an effective platinum catalyst for catalyzing hydrogenation reaction, and is a new environmentally friendly material. Specifically, the compound of the present application is (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II), the molecular structure of which is shown in Figure 1 The molecular structure is shown in formula (1):

[0028] Formula (1).

[0029] The structure of the compound of the present application is abbreviated as [Pt(5-NO2-ppy)(DMSO)Cl], the data is collected by Bruker Smart APEXII CCD instrument, the structure is analyzed and solved by SHELX program, and the molecular structure is processed by Diamond 3 software, and the schematic diagram of the molecular structure is shown in Figure 1 .

[0030] The structural unit of the compound of the present application belongs to monoclinic C2 / c (No. 15) group, and the cell parameters are: a = 7.9405(8) Å, b = 18.0744(18) Å, c = 21.513(2) Å, α = 90.00°, β = 98.7810(10)°, γ = 90.00°. The inventors have no duplication after checking in the Cambridge Crystallographic Data Centre (CCDC), and it is a new compound. The inventors apply for CCDC No.: 2275143.

[0031] The present application also provides a preparation method of the compound, comprising the following steps:

[0032] (1) 5-nitro-2-phenylpyridine and potassium chloroplatinite are suspended in ethylene glycol monoethyl ether, and the suspension is stirred at a specific temperature for several hours under nitrogen protection;

[0033] (2) The ethylene glycol monoethyl ether is removed by rotary evaporation, and dimethyl sulfoxide is added, and the temperature is controlled at a specific temperature for several hours;

[0034] (3) The orange-yellow block crystal is obtained by standing and volatilizing in an open beaker for several days, and the product (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) platinum (II) chloride is obtained by filtering and drying to constant weight.

[0035] In step (1), the molar ratio of potassium chloroplatinite to 5-nitro-2-phenylpyridine is 1: (2-5). Two 5-nitro-2-phenylpyridines and one potassium chloroplatinite form a coordination intermediate, which then undergoes the following reaction. Therefore, this molar ratio is appropriate. In addition, potassium chloroplatinite is relatively expensive, and appropriate ratio can reduce production cost and avoid waste of potassium chloroplatinite.

[0036] In step (1), the weight ratio of potassium chloroplatinite to ethylene glycol monoethyl ether is 1: (40-100). Ethylene glycol monoethyl ether is used as a solvent, and more solvent is beneficial to stirring and dissolving after coordination reaction, otherwise it cannot be normally reacted.

[0037] In step (1), the stirring temperature is 60-90°C, and the stirring time is 5-20 hours.

[0038] In step (2), the molar ratio of potassium chloroplatinite to dimethyl sulfoxide is 1: (500-1000). Dimethyl sulfoxide acts as a solvent, and a large amount is required for sufficient stirring. At the same time, dimethyl sulfoxide replaces one 5-nitro-2-phenylpyridine to form the target product.

[0039] In step (2), the stirring temperature is 5-25°C, and the stirring time is 5-25 hours.

[0040] In step (3), the standing crystallization time is 5-25 days, and the standing temperature is room temperature, which can be between 25-30°C.

[0041] In step (3), the drying temperature is 50-70°C.

[0042] The application also provides the use of the compound, and the compound is used as a catalyst for a hydrogen reduction process. Furthermore, the compound is used as a catalyst in a reaction of hydrogen reduction of a nitrobenzene derivative into an aniline.

[0043] Compared with the prior art, the application has the following beneficial effects:

[0044] 1. The application first synthesizes a complex (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II) with 5-nitro-2-phenylpyridine (5-NO2-ppy), dimethyl sulfoxide (DMSO), and chlorine (Cl) as ligands, which is abbreviated as [Pt(5-NO2-ppy)(DMSO)Cl].

[0045] 2. The preparation method of the compound (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II) in the application has a simple synthesis route and mild reaction conditions, and the finished product can be obtained by self-evaporation crystallization.

[0046] 3. The compound (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) chloroplatinum (II) in the application is used in a green and environmentally friendly hydrogen reduction process, has high catalytic efficiency and high catalytic yield, is strong in recyclability, is not easy to be poisoned, and will not cause impurities due to dehalogenation of the product, and is expected to be used in large-scale industrial production.

[0047] The application is further described below through specific examples.

[0048] Example 1

[0049] 5-nitro-2-phenylpyridine (0.2402 g, 0.0012 mol) and potassium chloroplatinite (1.6602 g, 0.0004 mol) are suspended in ethylene glycol monoethyl ether (90 ml, 83.7 g, 0.93 mol), and the suspension is stirred at 80°C for 10 hours under nitrogen protection. The ethylene glycol monoethyl ether is removed by rotary evaporation, and dimethyl sulfoxide (20 ml, 22 g, 0.28 mol) is added, and stirring is performed at a temperature of 20°C for 10 hours. The mixture is left to stand at room temperature (between 25-30°C) in an open beaker for 7 days to obtain orange-yellow block-shaped crystals, which are filtered and dried at 55°C±5°C to constant weight to obtain the finished product [Pt(5-NO2-ppy)(DMSO)Cl] (0.1777 g, 0.00034 mol), with a molar yield of 85%.

[0050] The orange-yellow crystals were identified:

[0051] Under microscope, the crystals with suitable size were selected and placed on a Bruker Smart APEX II CCD instrument to collect, with Mo-K radiation (λ = 0.71073 Å) as light source, in the range of 1.92° < θ < 25.00°, according to ω-2θ scanning mode, 10652 data were collected, among which there were 2699 independent diffraction points (R int = 0.0610), and 2397 observable points [I>2σ(I)]. The single crystal was analyzed by direct analysis method, the hydrogen atoms were determined by theoretical hydrogenation and manual hydrogenation, and the anisotropic temperature factors of other atoms were corrected by full matrix least squares method in SHELXTL program. The crystallographic data is shown in Table 1.

[0052] Table 1 Crystallographic data of compound [Pt(5-NO2-ppy)(DMSO)Cl]

[0053]

[0054] Example 2

[0055] 5-nitro-2-phenylpyridine (0.3003 g, 0.0015 mol) and potassium chloroplatinate (1.6602 g, 0.0004 mol) were suspended in ethylene glycol monoethyl ether (110 ml, 102.3 g, 1.14 mol), and the suspension was stirred at 70°C for 15 hours under nitrogen protection. The ethylene glycol monoethyl ether was removed by rotary evaporation, and dimethyl sulfoxide (15 ml, 16.5 g, 0.21 mol) was added, and stirred at 10°C for 18 hours. The orange-yellow block crystals were obtained by standing in an open beaker at room temperature (between 25-30°C) for 8 days, and the product [Pt(5-NO2-ppy)(DMSO)Cl] (0.1794 g, 0.00035 mol) was obtained by filtering and drying at 65°C±5°C to constant weight, with a molar yield of 88.3%.

[0056] Example 3

[0057] In order to fully illustrate the application of the new environmental protection material (5-nitro-2-phenylpyridine) (dimethyl sulfoxide) platinum (II) chloride in the green hydrogenation process, the product [Pt(5-NO2-ppy)(DMSO)Cl] of Example 1 was used to carry out hydrogenation experiments on halogen-containing phenyl derivatives.

[0058] (I) 2,6-dibromonitrobenzene was used as the reaction raw material, and [Pt(5-NO2-ppy)(DMSO)Cl] was used as the catalyst to carry out hydrogenation reaction in different solvents to prepare 2,6-dibromoaniline.

[0059] The 2,6-dibromonitrobenzene and the ground catalyst [Pt(5-NO2-ppy)(DMSO)Cl] were added into a 1L hydrogenation reactor, and 500ml solvent was added. After nitrogen replacement and hydrogen replacement, the hydrogenation reaction was carried out by opening the stirring and passing hydrogen. The reaction was monitored by TLC. The liquid and solid catalyst in the hydrogenation reactor were filtered as a whole, the filtrate was evaporated to dryness, weighed, and sent for liquid phase detection. The dehalogenation rate was detected by using o-bromoaniline and aniline as dehalogenation impurities.

[0060] The reaction parameters and results are shown in Table 2 below.

[0061] Table 2: Compound [Pt(5-NO2-ppy)(DMSO)Cl] hydrogenation experiment results

[0062]

[0063] As can be seen from Table 2, the compound has very high catalytic activity, and the dehalogenation rate is less than 0.1%.

[0064] (II) 2,6-dibromonitrobenzene as the raw material, the finished product [Pt(5-NO2-ppy)(DMSO)Cl] of Example 2 as the catalyst for hydrogenation reaction in methanol to prepare 2,6-dibromoaniline, and the catalyst was washed and reused multiple times.

[0065] The 2,6-dibromonitrobenzene and the ground catalyst [Pt(5-NO2-ppy)(DMSO)Cl] were added into a 1L hydrogenation reactor, and 500ml solvent was added. After nitrogen replacement and hydrogen replacement, the hydrogenation reaction was carried out by opening the stirring and passing hydrogen. The reaction was monitored by TLC. The liquid and solid catalyst in the hydrogenation reactor were filtered as a whole, the filtrate was evaporated to dryness, weighed, and sent for liquid phase detection. The dehalogenation rate was detected by using o-bromoaniline and aniline as dehalogenation impurities.

[0066] The reaction parameters and results are shown in Table 3 below.

[0067] Table 3: Compound [Pt(5-NO2-ppy)(DMSO)Cl] hydrogenation experiment results

[0068]

[0069] As can be seen from Table 3, from the 8th to the 10th in the table, due to the gradual accumulation of attachments that are not soluble in the washing agent methanol on the compound, the catalytic efficiency gradually decreases. As can be seen from the results in Table 3, the compound has strong recyclability and is not easy to be poisoned as a catalyst.

[0070] It should be understood that the application is not limited to the examples described above, which can be modified or transformed by a person of ordinary skill in the art in light of the above description, all such modifications and transformations being intended to be within the scope of the application.

Claims

1. A compound, characterized in that, The compound is (5-nitro-2-phenylpyridine)(dimethyl sulfoxide)chloroplatinum(II), and its molecular structure is shown in formula (1): The structural unit of the compound belongs to the monoclinic crystal system, group C2 / c (no. 15), and its cell parameters are: α=90.00°, β=98.7810(10)°, γ=90.00°.

2. A method for preparing the compound as described in claim 1, characterized in that, Includes the following steps: (1) 5-nitro-2-phenylpyridine and potassium chloride platinum ether were suspended in ethylene glycol monoethyl ether to obtain a suspension, and the suspension was stirred under nitrogen protection. (2) Remove the ethylene glycol monoethyl ether by rotary evaporation, then add dimethyl sulfoxide and stir; (3) The mixture was left to stand in the open to volatilize, and orange-yellow blocky crystals were obtained. The mixture was filtered and dried to constant weight to obtain the (5-nitro-2-phenylpyridine)(dimethyl sulfoxide)chloroplatinum(II).

3. The method for preparing the compound according to claim 2, characterized in that, In step (1), the molar ratio of potassium chloroplatinate to 5-nitro-2-phenylpyridine is in the range of 1:(2-5).

4. The method for preparing the compound according to claim 2, characterized in that, In step (1), the weight ratio of potassium chloroplatinate to ethylene glycol monoethyl ether is 1:(40-100).

5. The method for preparing the compound according to claim 2, characterized in that, The molar ratio of potassium chloroplatinate to dimethyl sulfoxide is 1:(500-1000).

6. The method for preparing the compound according to claim 2, characterized in that, In step (1), during the stirring of the suspension, the stirring temperature is 60-90°C and the stirring time is 5-20 hours; In step (2), the stirring process is carried out at a temperature of 5 to 25°C and for a duration of 5 to 25 hours.

7. The method for preparing the compound according to claim 2, characterized in that, In step (3), the settling time is 5 to 25 days, and the settling temperature is 25 to 30°C; In step (3), the temperature range during the drying process is 50 to 70°C.

8. An application of the compound as described in claim 1, characterized in that, The compound is used as a catalyst in a hydrogenation reduction process.

9. The application of the compound according to claim 8, characterized in that, The compound was used as a catalyst in the hydrogenation reduction of nitrobenzene derivatives to aniline.

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