A novel organic-inorganic hybrid catalytic material, a preparation method and application thereof

Abstract

The application relates to the technical field of material preparation and catalytic synthesis, in particular to a novel organic-inorganic hybrid catalytic material, a preparation method and application thereof. The organic-inorganic hybrid catalytic material is prepared by coordination of organic acid and metal cations of a hydrotalcite-like substance in a solvent; the content of the hydrotalcite-like substance in the system is 25-100 g / L; and the content of the organic acid in the system is 0.02-0.5 mol / L. The novel organic-inorganic hybrid catalytic material is applied to the oxidation activation of aromatic side chain α -C-H bonds, green and pollution-free molecular oxygen is used as the only oxidant, and corresponding ketone and ester compounds are obtained through high-efficiency oxidation. The oxidation capacity of the catalyst is improved; meanwhile, the acid-base property of the surface of the catalytic material is regulated, so that the generation of by-products is reduced, and the novel organic-inorganic hybrid catalytic material exhibits high-efficiency activation capacity and excellent selectivity in the oxidation process of aromatic side chain α -C-H bonds.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of material preparation and catalytic synthesis, and particularly relates to a novel organic-inorganic hybrid catalytic material, a preparation method and application thereof. BACKGROUND

[0002] At present, the commonly used oxidation systems for high-efficiency selective oxidation and activation of aromatic side chain alpha-C-H bond mainly include tert-butyl hydroperoxide, NaClO, KMnO4 and H2O2, etc. This brings problems of cost, safety and atom economy. The reaction system using green and economical molecular oxygen as an oxidant often uses homogeneous metal complexes or metal oxides as catalysts, and the homogeneous system is highly efficient, but the catalyst cannot be recycled and reused; and the heterogeneous metal oxide system has low catalytic activity and poor selectivity, and the reaction system is high in temperature and pressure.

[0003] The information disclosed in this BACKGROUND section is only for the purpose of enhancing the understanding of the general background of the application and should not be taken as an acknowledgement or any form of suggestion that this information forms prior art in the field. SUMMARY

[0004] The present application aims to develop a novel organic-inorganic hybrid catalytic material, which has stronger oxidation capacity, thereby having higher efficient catalysis of aromatic side chain alpha-C-H bond oxidation and activation; the surface acidity and alkalinity of the novel organic-inorganic hybrid catalytic material can be regulated, thereby improving the selectivity of the target product; and the novel organic-inorganic hybrid catalytic material can still maintain good catalytic effect after being recycled for multiple times. The problems of the prior art system, such as the need for strong oxidants, high temperature and pressure, the inability to recycle homogeneous catalysts and the low yield of heterogeneous catalysts, are solved.

[0005] In order to solve the above technical problems, the technical solution adopted by the present application is as follows:

[0006] A novel organic-inorganic hybrid catalytic material is prepared by coordination of an organic acid and metal cations of a hydrotalcite-like substance in a solvent.

[0007] The content of the hydrotalcite-like substance in the system is 25-100 g / L; and the content of the organic acid in the system is 0.02-0.5 mol / L. The smaller the ratio of the organic acid to the hydrotalcite-like substance, the more the metal cations of the hydrotalcite-like substance are coordinated with the organic acid; and the hybridization rate of the catalytic material is reduced. The larger the ratio of the organic acid to the hydrotalcite-like substance, the more the hydrotalcite-like substance is dissolved, thereby reducing the yield of the catalytic material. Therefore, the present application limits the above range to ensure that the prepared organic-inorganic hybrid catalytic material has high yield and selectivity.

[0008] As a preferred, the general formula of the hydrotalcite-like substance is M(II)M(III)-LDH; wherein M(II) is Ni2+ Mg 2+ 、Zn 2 + 、Co 2+ 、Cu 2+ 、Ba 2+ , Ca 2+ Any one or two of the following, wherein M(III) is Al 3+ 、Fe 3+ 、Ti 3+ Cr 3+ 、V 3+ 、Co 3+ 、Mn 3 + 、Ga 3+ 、In 3+ Any one of .

[0009] As further preferred, wherein M(II) is Ni 2+ Mg 2+ , Ca 2+ 、Zn 2+ 、Co 2+ Where M(III) is Mn 3+ 、Fe 3 + ; M(II)Mn-LDH and M(II)Fe-LDH were obtained.

[0010] Preferably, the carboxyl group in the organic acid coordinates with the metal cation in the hydrotalcite-like substance.

[0011] Preferably, the organic acid is any one of the following (a) to (e);

[0012]

[0013] Wherein R represents: H, X (F, Cl, Br, I), –OH, –COOH, –CH3, –OCH3, –C(CH3)3, –NO2, –CF3, –NH2; preferably R is: H, F, Cl, Br, –COOH, –OCH3, –C(CH3)3, –NO2; wherein n = 1 to 10, preferably n is 2, 3, or 4. Strong electron-donating groups and long-chain organic acids are not conducive to the synthesis of organic-inorganic hybrid catalytic materials, so R and n in the present invention are preferably above.

[0014] Preferably, the solvent is either dodecane or diphenyl ether.

[0015] The second purpose of the present invention is to develop a method for preparing a novel organic-inorganic hybrid catalytic material, which has the same technical effect.

[0016] In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

[0017] A method for preparing a novel organic-inorganic hybrid catalytic material, the method steps are as follows:

[0018] (1) Preparation of hydrotalcite-like

[0019] S11: dissolving the desired metal salt in deionized water to form a mixed metal salt solution A; dissolving sodium carbonate in deionized water to form solution B; and dissolving sodium hydroxide in deionized water to form solution C; the molar concentration ratio of the three solutions is A:B:C=2:1:6;

[0020] S12: Add solution B to a round-bottom four-necked flask, add solutions A and C dropwise to the four-necked round-bottom flask, control the pH value between 9-11, and continuously stir for 24 hours to form a suspension; if the reaction time is too long, the structure of the hydrotalcite-like material will not be affected; if the reaction time is short, the crystallinity of the hydrotalcite-like material will be low.

[0021] S13: The formed suspension is washed with deionized water until neutral, filtered, and dried to obtain a hydrotalcite-like (LDH) material;

[0022] (2) Preparation of organic-inorganic hybrid catalytic materials

[0023] S14: adding the prepared hydrotalcite-like substance, an organic acid, and a solvent into a reactor to carry out a reaction. After the reaction, the product is washed with ethyl acetate, filtered, and dried to obtain a novel organic-inorganic hybrid catalytic material.

[0024] Preferably, in step S14, the synthesis temperature of the novel organic-inorganic hybrid catalytic material is 60 to 180° C., preferably 120° C. When the reaction temperature is too high, the structure of the hydrotalcite-like material collapses, and the novel organic-inorganic hybrid catalytic material cannot be prepared. When the reaction temperature is too low, the activity of the organic acid is low, and the hydrotalcite-like metal cation cannot coordinate with the organic acid to prepare the novel organic-inorganic hybrid catalytic material.

[0025] Preferably, in step S14, the synthesis time of the new organic-inorganic hybrid catalytic material is 2 to 48 hours. If the reaction time is too long, the structure of the new organic-inorganic hybrid catalytic material will not be changed; if the reaction time is short, the metal cations of the hydrotalcite-like material will be partially coordinated with the organic acid, resulting in the inability to prepare a stable new organic-inorganic hybrid catalytic material.

[0026] A third objective of the present invention is to develop a method for applying a novel organic-inorganic hybrid catalytic material to the oxidative activation of α-C-H bonds in aromatic side chains for the preparation of esters (Formula II) and ketones (Formula IV). This method overcomes the problems of existing systems, such as the need for strong oxidants, high temperatures and pressures, the inability to recycle homogeneous catalysts, and the low yields of heterogeneous catalysts. The specific steps are as follows:

[0027] The compound shown in Formula I or Formula III is used as a reaction substrate, and the novel organic-inorganic hybrid catalytic material is added to a reactor; oxygen is used as an oxidant and introduced into the reactor for a catalytic reaction; after the reaction, the reaction solution is filtered, washed with ethyl acetate, and then distilled under reduced pressure and separated by column chromatography to obtain the target product of Formula II or target product IV;

[0028]

[0029] In formula I and II, R 1 Representative: H, F, Cl, Br, methyl, methoxy, trifluoromethyl, tert-butyl, nitro; Since strong electron-donating groups are not conducive to the reaction, R in the present invention is 1 Select the above groups.

[0030] In formula I and II, R 2 Representative: phenyl, C1~C 20 Alkyl; preferably phenyl, n-butyl, n-decyl, n-tetradecyl. Since long-chain alkane groups are not conducive to the reaction, R in the present invention is 2 Select the above groups.

[0031] In formula III and IV, R 3 Representative: H, F, Cl, Br, methyl, methoxy, trifluoromethyl, tert-butyl, nitro; preferably H, Br, methyl, methoxy; Since strong electron-withdrawing groups are not conducive to the reaction, R in the present invention is 3 Select the above groups.

[0032] In formula III and IV, R 4 Representative: phenyl.

[0033] Preferably, the solvent is 1,3,5-trimethylbenzene, dodecane, dimethyl sulfoxide, N,N-dimethylformamide, diphenyl ether, diethylene glycol dimethyl ether, γ-valerolactone, or cyclohexanone, with dodecane being preferred. Catalytic oxidation performance is related to solvent polarity and oxygen solubility. Therefore, the present invention prefers dodecane as the solvent, which has low polarity and high oxygen solubility.

[0034] Preferably, the ratio of the novel organic-inorganic hybrid catalytic material to the reaction substrate is 10 to 100 g / mol, preferably 25 g / mol. When the catalyst dosage is too high, the conversion rate of Formula I or Formula III does not increase significantly, reducing the economic efficiency of the reaction system; when the catalyst dosage is too low, the conversion rate of Formula I or Formula III decreases significantly.

[0035] Preferably, the oxygen flow rate is 50 mL / min; the reaction temperature is 100-140°C, preferably 120°C. High reaction temperatures increase the activity of the reaction system, resulting in reduced selectivity for the target product; low reaction temperatures decrease the activity of the reaction system, resulting in a reduced yield of the target product. The reaction time is 3-30 hours.

[0036] Compared with the prior art, the beneficial effects of the present invention are mainly:

[0037] a) This invention uses hydrotalcite-like compounds as precursors and organic acids as organic ligands. By utilizing the coordination between the organic acid and the metal cations of the hydrotalcite-like compounds, a novel organic-inorganic hybrid catalytic material is synthesized for the first time. This combines the advantages of both metal complex and metal oxide reaction systems.

[0038] b) The present invention uses green and economical molecular oxygen as an oxidant, a novel organic-inorganic hybrid catalytic material as a catalyst, and dodecane as a solvent to efficiently oxidize Formula I and Formula III to obtain the corresponding target products. The coordination of an organic acid and a hydrotalcite-like cation enhances the oxidizing ability of the novel organic-inorganic hybrid catalytic material and improves the conversion rate of Formula I. The organic acid regulates the acidity and alkalinity of the hydrotalcite-like surface, thereby improving the selectivity of the target product.

[0039] c) The novel organic-inorganic hybrid catalytic material disclosed herein is recyclable. Even after five cycles, its catalytic efficiency remains above 90%. This solves the problems of existing oxidation systems, such as the need for the addition of strong oxidants, the inability to recycle high-efficiency homogeneous catalysts, and the high-temperature, high-pressure, and low-yield requirements of heterogeneous catalytic systems. Compared to existing technologies, the present invention offers a simple and easy-to-use process, an environmentally friendly synthesis method, and excellent application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is the XRD pattern of the novel organic-inorganic hybrid catalytic material proposed in the present invention. a is the precursor Ni2Mg2Mn-LDH, b is the novel organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn coordinated by hydrotalcite-like Ni2Mg2Mn-LDH and benzoic acid (BA), and c is benzoic acid

[0041] Figure 2This is the TG spectrum of the new organic-inorganic hybrid catalytic material proposed in the present invention. a is the precursor Ni2Mg2Mn-LDH, b is the new organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn coordinated by hydrotalcite-like Ni2Mg2Mn-LDH and benzoic acid, and c is benzoic acid.

[0042] Figure 3 This is the SEM image of the novel organic-inorganic hybrid catalytic material proposed in the present invention. a is the precursor Ni2Mg2Mn-LDH, b is the novel organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn coordinated by hydrotalcite-like Ni2Mg2Mn-LDH and benzoic acid.

[0043] Figure 4 This is the FT-IR spectrum of the novel organic-inorganic hybrid catalytic material proposed in the present invention. a is the precursor Ni2Mg2Mn-LDH, b is the novel organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn coordinated by hydrotalcite-like Ni2Mg2Mn-LDH and benzoic acid, c is benzoic acid, and d is potassium benzoate. DETAILED DESCRIPTION

[0044] The present invention will be further described below through specific implementation methods, but the protection scope of the present invention is not limited thereto.

[0045] In a specific embodiment of the present invention, the sources of commercially available materials are as follows:

[0046]

[0047]

[0048] 1. Preparation of novel organic-inorganic hybrid catalytic materials

[0049] Example 1:

[0050] A method for preparing a novel organic-inorganic hybrid catalytic material, the method steps are as follows:

[0051] (1) Preparation of Ni2Mg2Mn-LDH

[0052] Prepare 90 mL of a mixed metal salt solution A (Ni(NO3)2·6H2O (0.036 mol, 10.47 g), Mg(NO3)2·6H2O (0.036 mol, 9.23 g), and MnCl2·4H2O (0.018 mol, 3.56 g); 40 mL of a 0.5 mol / L Na2CO3 solution B; and 60 mL of a 3 mol / L NaOH solution C. Add solution B to a four-necked round-bottom flask, then add solutions A and C dropwise to the flask. Control the pH between 9 and 11, and stir continuously for 24 hours to form a suspension. The resulting suspension is washed with deionized water until neutral, filtered, and dried to obtain Ni2Mg2Mn-LDH.

[0053] (2) Preparation of organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn

[0054] Weigh 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of benzoic acid and add them to the reactor, add 2 mL of dodecane, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120 ° C for 4 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove benzoic acid and dodecane, and dry at 70 ° C for 12 hours to obtain a new organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn.

[0055] Example 2:

[0056] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0057] (2) Preparation of novel organic-inorganic hybrid catalytic material AA-Ni2Mg2Mn:

[0058] Weigh 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of 4-methoxybenzoic acid (AA) and add them to the reactor, add 2 mL of dodecane, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120 ° C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove 4-methoxybenzoic acid and dodecane, and dry at 70 ° C for 12 hours to obtain a new organic-inorganic hybrid catalytic material AA-Ni2Mg2Mn.

[0059] Example 3:

[0060] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0061] (2) Preparation of a novel organic-inorganic hybrid catalytic material TBA-Ni2Mg2Mn:

[0062] Take 100 mg of Ni2Mg2Mn-LDH, 0.2 mmol of 4-tert-butyl benzoic acid (TBA) into the reactor, add 2 mL of dodecane, seal the reaction tube, check the airtightness of the reaction tube with a water pump, react at 120°C for 12 h, after the reaction is completed, remove 4-tert-butyl benzoic acid and dodecane by ethyl acetate extraction and washing, dry at 70°C for 12 h to obtain a new type of organic-inorganic hybrid catalytic material TBA-Ni2Mg2Mn.

[0063] Example 4:

[0064] (1) Prepare Ni2Mg2Mn-LDH according to the preparation method of Example 1;

[0065] (2) Prepare a new type of organic-inorganic hybrid catalytic material TA-Ni2Mg2Mn:

[0066] Take 100 mg of Ni2Mg2Mn-LDH, 0.2 mmol of 4-tert-butyl benzoic acid (TBA) into the reactor, add 2 mL of dodecane, seal the reaction tube, check the airtightness of the reaction tube with a water pump, react at 120°C for 12 h, after the reaction is completed, remove 4-tert-butyl benzoic acid and dodecane by ethyl acetate extraction and washing, dry at 70°C for 12 h to obtain a new type of organic-inorganic hybrid catalytic material TBA-Ni2Mg2Mn.

[0067] Example 5:

[0068] (1) Prepare Ni2Mg2Mn-LDH according to the preparation method of Example 1;

[0069] (2) Prepare a new type of organic-inorganic hybrid catalytic material FA-Ni2Mg2Mn:

[0070] Take 100 mg of Ni2Mg2Mn-LDH, 0.2 mmol of 4-tert-butyl benzoic acid (TBA) into the reactor, add 2 mL of dodecane, seal the reaction tube, check the airtightness of the reaction tube with a water pump, react at 120°C for 12 h, after the reaction is completed, remove 4-tert-butyl benzoic acid and dodecane by ethyl acetate extraction and washing, dry at 70°C for 12 h to obtain a new type of organic-inorganic hybrid catalytic material TBA-Ni2Mg2Mn.

[0071] Example 6:

[0072] (1) Prepare Ni2Mg2Mn-LDH according to the preparation method of Example 1;

[0073] (2) Prepare a new type of organic-inorganic hybrid catalytic material CA-Ni2Mg2Mn:

[0074] Weigh 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of 4-chlorobenzoic acid (CA) and add them to the reactor, add 2 mL of dodecane, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120 ° C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove 4-chlorobenzoic acid and dodecane, and dry at 70 ° C for 12 hours to obtain a new organic-inorganic hybrid catalytic material CA-Ni2Mg2Mn.

[0075] Example 7:

[0076] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0077] (2) Preparation of a new organic-inorganic hybrid catalytic material BBA-Ni2Mg2Mn:

[0078] Weigh 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of 4-bromobenzoic acid (BBA) and add them to the reactor, add 2 mL of dodecane, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120°C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove 4-bromobenzoic acid and dodecane, and dry at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material BBA-Ni2Mg2Mn.

[0079] Example 8:

[0080] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0081] (2) Preparation of novel organic-inorganic hybrid catalytic material NA-Ni2Mg2Mn:

[0082] Weigh 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of 4-nitrobenzoic acid (NA) and add them to the reactor, add 2 mL of dodecane, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120 ° C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove 4-nitrobenzoic acid and dodecane, and dry at 70 ° C for 12 hours to obtain a new organic-inorganic hybrid catalytic material NA-Ni2Mg2Mn.

[0083] Example 9:

[0084] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0085] (2) Preparation of a new organic-inorganic hybrid catalytic material BTA-Ni2Mg2Mn:

[0086] 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of n-butyric acid (BTA) were weighed and added to the reactor, 2 mL of dodecane was added, the reaction tube was sealed, and the airtightness of the reaction tube was checked with a water pump. The reaction was carried out at 120°C for 12 hours. After the reaction was completed, the n-butyric acid and dodecane were removed by filtration with ethyl acetate, and the mixture was dried at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material BTA-Ni2Mg2Mn.

[0087] Example 10:

[0088] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0089] (2) Preparation of novel organic-inorganic hybrid catalytic material VA-Ni2Mg2Mn:

[0090] Weigh 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of valeric acid (VA) and add them to the reactor, add 2 mL of dodecane, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120°C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove valeric acid and dodecane, and dry at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material VA-Ni2Mg2Mn.

[0091] Example 11:

[0092] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0093] (2) Preparation of a novel organic-inorganic hybrid catalytic material HA-Ni2Mg2Mn:

[0094] 100 mg of Ni2Mg2Mn-LDH and 0.2 mmol of n-hexanoic acid (HA) were weighed and added to the reactor, 2 mL of dodecane was added, the reaction tube was sealed, and the airtightness of the reaction tube was checked with a water pump. The reaction was carried out at 120°C for 12 hours. After the reaction was completed, the n-hexanoic acid and dodecane were removed by filtration and washing with ethyl acetate, and the mixture was dried at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material HA-Ni2Mg2Mn.

[0095] Example 12:

[0096] (1) Ni2Mg2Mn-LDH was prepared according to the preparation method of Example 1;

[0097] (2) Preparation of a new organic-inorganic hybrid catalytic material APA-Ni2Mg2Mn:

[0098] Take 100 mg of Ni2Mg2Mn-LDH, 0.2 mmol of adipic acid (APA) into the reactor, add 2 mL of dodecane, seal the reaction tube, check the airtightness of the reaction tube with a water pump, react at 120°C for 12 h, after the reaction is completed, remove the adipic acid and dodecane by extraction and washing with ethyl acetate, and dry at 70°C for 12 h to obtain a new organic-inorganic hybrid catalytic material APA-Ni2Mg2Mn.

[0099] Example 13:

[0100] (1) Prepare Ni2Mg2Mn-LDH according to the preparation method of Example 1;

[0101] (2) Prepare a new organic-inorganic hybrid catalytic material CHBA-Ni2Mg2Mn:

[0102] Take 100 mg of Ni2Mg2Mn-LDH, 0.2 mmol of cyclohexyl formic acid (CHBA) into the reactor, add 2 mL of dodecane, seal the reaction tube, check the airtightness of the reaction tube with a water pump, react at 120°C for 12 h, after the reaction is completed, remove the cyclohexyl formic acid and dodecane by extraction and washing with ethyl acetate, and dry at 70°C for 12 h to obtain a new organic-inorganic hybrid catalytic material CHBA-Ni2Mg2Mn.

[0103] Example 14:

[0104] (1) Prepare Ni2Mn-LDH

[0105] Prepare 200 mL of an aqueous mixed metal salt solution A of Ni(NO3)2·6H2O (0.08 mol, 23.265 g) and MnCl2·4H2O (0.04 mol, 7.916 g); prepare 100 mL of a 5.6 g aqueous ammonia solution B; prepare 100 mL of a 3.2 g NaOH solution C. Add solution B and C into a round-bottom four-necked flask and mix well, then add solution A dropwise into the four-necked round-bottom flask, stir for 1 h after the addition is completed, warm up to 50°C and age for 20 h, wash the suspension with deionized water until neutral, filter, and dry to obtain Ni2Mn-LDH.

[0106] (2) Prepare an organic-inorganic hybrid catalytic material BA-Ni2Mn:

[0107] Specific steps: take 100 mg of Ni2Mn-LDH, 0.2 mmol of benzoic acid into the reactor, add 2 mL of diphenyl ether, seal the reaction tube, check the airtightness of the reaction tube with a water pump, react at 120°C for 12 h, after the reaction is completed, remove the benzoic acid and diphenyl ether by extraction and washing with ethyl acetate, and dry at 70°C for 12 h to obtain a new organic-inorganic hybrid catalytic material BA-Ni2Mn.

[0108] Example 15:

[0109] (1) Preparation of Ni2Zn2Mn-LDH

[0110] Prepare 90 mL of a mixed metal salt solution A (Ni(NO3)2·6H2O (0.036 mol, 10.47 g), Zn(NO3)2·6H2O (0.036 mol, 10.71 g), and MnCl2·4H2O (0.018 mol, 3.56 g); 40 mL of a 0.5 mol / L Na2CO3 solution B; and 60 mL of a 3 mol / L NaOH solution C. Add solution B to a four-necked round-bottom flask, then add solutions A and C dropwise to the flask. Control the pH between 9 and 11, and stir continuously for 24 hours to form a suspension. The resulting suspension is washed with deionized water until neutral, filtered, and dried to obtain Ni2Zn2Mn-LDH.

[0111] (2) Preparation of a new organic-inorganic hybrid catalytic material BA-Ni2Zn2Mn:

[0112] Specific steps: weigh 100 mg of Ni2Zn2Mn-LDH and 0.2 mmol of benzoic acid and add them to the reactor, add 2 mL of diphenyl ether, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120°C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove benzoic acid and diphenyl ether, and dry at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material BA-Ni2Zn2Mn.

[0113] Example 16:

[0114] (1) Preparation of Ni2Ca2Mn-LDH

[0115] Prepare 90 mL of a mixed metal salt solution A containing Ni(NO3)2·6H2O (0.036 mol, 10.47 g), Ca(NO3)2·4H2O (0.036 mol, 8.5 g), and MnCl2·4H2O (0.018 mol, 3.56 g); 40 mL of a 0.5 mol / L Na2CO3 solution B; and 60 mL of a 3 mol / L NaOH solution C. Add solution B to a four-necked round-bottom flask, then add solutions A and C dropwise to the flask. Control the pH between 9 and 11, and stir continuously for 24 hours to form a suspension. The resulting suspension is washed with deionized water until neutral, filtered, and dried to obtain Ni2Ca2Mn-LDH.

[0116] Preparation of new organic-inorganic hybrid catalytic material BA-Ni2Ca2Mn:

[0117] Specific steps: weigh 100 mg of Ni2Ca2Mn-LDH and 0.2 mmol of benzoic acid and add them into the reactor, add 2 mL of diphenyl ether, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120°C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove benzoic acid and diphenyl ether, and dry at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material BA-Ni2Ca2Mn.

[0118] Example 17:

[0119] (1) Preparation of Ni2Co2Mn-LDH

[0120] Prepare 90 mL of a mixed metal salt solution A (Ni(NO3)2·6H2O (0.036 mol, 10.47 g), Co(NO3)2·6H2O (0.036 mol, 10.48 g), and MnCl2·4H2O (0.018 mol, 3.56 g); 40 mL of a 0.5 mol / L Na2CO3 solution B; and 60 mL of a 3 mol / L NaOH solution C. Add solution B to a four-necked round-bottom flask, then add solutions A and C dropwise to the flask. Control the pH between 9 and 11, and stir continuously for 24 hours to form a suspension. The resulting suspension is washed with deionized water until neutral, filtered, and dried to obtain Ni2Co2Mn-LDH.

[0121] (2) Preparation of a new organic-inorganic hybrid catalytic material BA-Ni2Co2Mn:

[0122] Specific steps: weigh 100 mg of Ni2Co2Mn-LDH and 0.2 mmol of benzoic acid and add them to the reactor, add 2 mL of diphenyl ether, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120°C for 12 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove benzoic acid and diphenyl ether, and dry at 70°C for 12 hours to obtain a new organic-inorganic hybrid catalytic material BA-Ni2Co2Mn.

[0123] Example 18:

[0124] (1) Preparation of Ni2Fe-LDH

[0125] A 90 mL aqueous solution of mixed metal salts of Ni(NO3)2·6H2O (0.06 mol, 17.45 g) and FeSO4·7H2O (0.03 mol, 8.34 g) was prepared; a 40 mL solution of Na2CO3 (0.5 mol / L) was prepared; and a 60 mL solution of NaOH (3 mol / L) was prepared. Solution B was added to a round-bottomed four-necked flask, and solutions A and C were added dropwise to the four-necked round-bottomed flask while controlling the pH value to be between 9 and 11, and a suspension was formed after 24 h of constant stirring; the suspension was washed with deionized water until neutral, filtered, and dried to obtain Ni2Fe-LDH.

[0126] (2) Preparation of a new organic-inorganic hybrid catalytic material BA-Ni2Fe

[0127] Specific steps: 100 mg of Ni2Fe-LDH and 0.2 mmol of benzoic acid were added to a reactor, 2 mL of diphenyl ether was added, the reaction tube was sealed, the airtightness of the reaction tube was checked with a water pump, and the reaction was carried out at 120°C for 24 h. After the reaction was completed, ethyl acetate was used to extract and wash to remove the benzoic acid and diphenyl ether, and drying was carried out at 70°C for 24 h to obtain a new organic-inorganic hybrid catalytic material BA-Ni2Fe.

[0128] Example 19:

[0129] (1) Preparation of Mg2Fe-LDH

[0130] A 90 mL aqueous solution of mixed metal salts of Mg(NO3)2·6H2O (0.06 mol, 15.39 g) and FeSO4·7H2O (0.03 mol, 8.34 g) was prepared; a 40 mL solution of Na2CO3 (0.5 mol / L) was prepared; and a 60 mL solution of NaOH (3 mol / L) was prepared. Solution B was added to a round-bottomed four-necked flask, and solutions A and C were added dropwise to the four-necked round-bottomed flask while controlling the pH value to be between 9 and 11, and a suspension was formed after 24 h of constant stirring; the suspension was washed with deionized water until neutral, filtered, and dried to obtain Mg2Fe-LDH.

[0131] (2) Preparation of a new organic-inorganic hybrid catalytic material BA-Mg2Fe

[0132] Specific steps: 100 mg of Mg2Fe-LDH and 0.2 mmol of benzoic acid were added to a reactor, 2 mL of diphenyl ether was added, the reaction tube was sealed, the airtightness of the reaction tube was checked with a water pump, and the reaction was carried out at 120°C for 24 h. After the reaction was completed, ethyl acetate was used to extract and wash to remove the benzoic acid and diphenyl ether, and drying was carried out at 70°C for 24 h to obtain a new organic-inorganic hybrid catalytic material BA-Mg2Fe.

[0133] Example 20:

[0134] (1) Preparation of Co2Fe-LDH

[0135] Prepare 90 mL of a mixed metal salt solution A of Co(NO3)2·6H2O (0.06 mol, 17.46 g) and FeSO4·7H2O (0.03 mol, 8.34 g); 40 mL of a 0.5 mol / L Na2CO3 solution B; and 60 mL of a 3 mol / L NaOH solution C. Add solution B to a four-necked round-bottom flask, then add solutions A and C dropwise to the flask. Control the pH between 9 and 11, and stir continuously for 24 hours to form a suspension. The resulting suspension is washed with deionized water until neutral, filtered, and dried to obtain Co2Fe-LDH.

[0136] (2) Preparation of a novel organic-inorganic hybrid catalytic material BA-Co2Fe:

[0137] Specific steps: weigh 100 mg of Co2Fe-LDH and 0.2 mmol of benzoic acid and add them to the reactor, add 2 mL of diphenyl ether, seal the reaction tube, check the tightness of the reaction tube with a water pump, react at 120°C for 24 hours, and after the reaction is completed, filter and wash with ethyl acetate to remove benzoic acid and diphenyl ether, and dry at 70°C for 24 hours to obtain a new organic-inorganic hybrid catalytic material BA-Co2Fe.

[0138] 2. Application of Catalyst

[0139] Example 21

[0140] The novel organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn prepared in Example 1 of the present invention was applied to the oxidation reaction of benzyl methyl ether.

[0141] The specific operating conditions are:

[0142] In a reactor, 1 mmol of benzyl methyl ether, 25 mg of BA-Ni2Mg2Mn, and 2 mL of dodecane were added and mixed thoroughly. An air pump was used to test the reactor's airtightness and extract air from the tube. The reactor was then connected to oxygen and heated to 120°C for 5 hours. Gas chromatography peak internal standard analysis of the reaction solution revealed a conversion of 95% for the raw material benzyl methyl ether and a selectivity for 99% for methyl benzoate.

[0143] Example 22

[0144] In a reactor, add 1 mmol of Formula I and Formula III (Formulas (1-1) to (1-15)), 25 mg of BA-Ni2Mg2Mn, and 2 mL of dodecane and mix thoroughly. Use an air pump to check the reactor's airtightness and extract air from the tube. Connect the reactor to oxygen and heat to 120°C for 2 to 30 hours. Wash and filter with ethyl acetate. Distill the filtrate under reduced pressure to remove the ethyl acetate. Column chromatography is then performed using a mixture of ethyl acetate and petroleum ether in a volume ratio of 1:30 as the eluent. Collect the eluate containing the target compound and evaporate the solvent to obtain compounds of Formulas II and IV (Formulas (2-1) to (2-15)).

[0145] The reaction results are shown in Table 1:

[0146] Table 1 Oxidation reaction results of different reaction substrates

[0147]

[0148]

[0149]

[0150] The product characterization is as follows:

[0151] The isolated yield of methyl 4-methylbenzoate (Formula (2-2)) was 87% (131 mg). Colorless oil; 1 H NMR (500MHz, CDCl3) δ7.93 (d, J = 8.1 Hz, 2H), 7.23 (d, J = 8.1 Hz, 2H), 3.89 (s, 3H), 2.40 (s, 3H). 13 C NMR (126MHz, CDCl3) δ167.1,143.5,129.6,129.0,127.4,51.9,21.6.

[0152] Methyl 4-nitrobenzoate (Formula (2-3)), isolated in 89% yield (161 mg). Yellow oily solid; 1 H NMR (500MHz, CDCl3) δ8.25 (d, J = 8.8Hz, 2H), 8.19–8.15 (m, 2H), 3.95 (s, 3H). 13 C NMR (126MHz, CDCl3) δ165.1,150.5,135.4,130.7,123.5,52.8.

[0153] Methyl 4-chlorobenzoate (Formula (2-4)), isolated in 79% yield (134 mg). Colorless oil; 1H NMR (500MHz, CDCl3) δ7.99–7.94 (m, 2H), 7.40 (d, J = 8.5Hz, 2H), 3.91 (s, 3H). 13 C NMR (126MHz, CDCl3) δ166.2,139.3,131.0,128.7,128.6,52.2.

[0154] Butyl benzoate (Formula (2-5)), isolated in 69% yield (123 mg). Colorless oil; 1 H NMR (500MHz, CDCl3) δ8.09–8.03(m,2H),7.59–7.53(m,1H),7.44(dd,J=10.7,4.8Hz,2 H),4.34(t,J=6.6Hz,2H),1.79–1.74(m,2H),1.53–1.47(m,2H),1.00(t,J=7.4Hz,3H). 13 C NMR (126MHz, CDCl3) δ166.7,132.8,130.5,129.53,128.3,64.8,30.8,19.3,13.8.

[0155] Benzoic acid decaester (Formula (2-6)), isolated yield 73% (191 mg). Colorless oil; 1 H NMR(300MHz, CDCl3)δ8.04(dd,J=5.2,3.3Hz,2H),7.60–7.50(m,1H),7.43(dd,J=10.3,4.6Hz,2H) ,4.31(t,J=6.7Hz,2H),1.81–1.71(m,2H),1.66–1.51(m,2H),1.27(s,12H),0.88(t,J=6.7Hz,3H). 13 C NMR (75MHz, CDCl3) δ166.7,132.8,130.5,129.5,128.3,65.2,31.9,29.6,29.3,29.3,28.7,26.1,22.7,14.1.

[0156] Tetradecyl benzoate (Formula (2-7)), isolated in 63% yield (200 mg). Colorless oil; 1H NMR (300MHz, CDCl3) δ8.07–8.02(m,2H),7.59–7.51(m,1H),7.47–7.39(m,2H),4.31(t,J=6.7 Hz,2H),1.82–1.70(m,2H),1.44(dd,J=8.5,5.0Hz,2H),1.26(s,20H),0.88(t,J=6.7Hz,3H). 13 CNMR (75MHz, CDCl3) δ166.7,132.8,130.6,129.6,128.3,65.2,32.0,29.7,29.7,29.6,29.6,29.4,29.3,28.7,26.1,22.7,14.2.

[0157] Benzyl benzoate (Formula (2-8)), isolated in 75% yield (159 mg). Colorless oil; 1 H NMR (500MHz, CDCl3) δ8.12–8.05(m,2H),7.55(dd,J=10.6,4.2Hz,1H),7.46–7.33(m,7H),5.37(s,2H). 13 C NMR (126MHz, CDCl3) δ166.4,136.1,133.0,130.1,129.7,129.5,128.6,128.5,128.3,128.3,128.3,128.2,128.1,66.6.

[0158] Dimethyl terephthalate (Formula (2-9)), isolated in 82% yield (159 mg). White solid; 1 H NMR (500MHz, CDCl3) δ8.09 (s, 4H), 3.94 (s, 6H). 13 C NMR (126MHz, CDCl3) δ166.3,133.9,129.5,52.4.

[0159] Methyl 2-naphthoate (Formula (2-10)), isolated in 78% yield (145 mg). White solid; 1 H NMR(500MHz, CDCl3)δ8.65(s,1H),8.10(dd,J=8.6,1.5Hz,1H),7.98(d,J=8.1 Hz,1H),7.94–7.89(m,2H),7.60(ddd,J=15.0,14.1,7.0Hz,2H),4.01(s,3H). 13C NMR (126MHz, CDCl3) δ167.3,135.5,132.5,131.1,129.4,128.3,128.2,127.8,127.4,126.7,125.3,52.3.

[0160] 3. Comparative Example

[0161] Comparative Example 1

[0162] The oxidation of benzyl ether using hydrotalcite-like Ni2Mg2Mn-LDH catalyzed the following reaction steps: 1 mmol of benzyl ether, 25 mg of Ni2Mg2Mn-LDH, and 2 mL of dodecane were added, with an oxygen flow rate of 50 mL / min, and the reaction was carried out at 120°C for 5 hours. Gas chromatography peak internal standard analysis of the reaction solution revealed a conversion of 34% for benzyl ether and a selectivity of 61% for methyl benzoate.

[0163] Comparative Example 2

[0164] The oxidation of benzyl methyl ether using the organic-inorganic hybrid material BA-Ni2Mg2Mn was catalyzed by the following reaction steps: 1 mmol of benzyl methyl ether, 25 mg of BA-Ni2Mg2Mn, and 2 mL of dodecane were added, with an air flow rate of 50 mL / min, and the reaction was carried out at 120°C for 5 hours. Gas chromatography peak internal standard analysis of the reaction solution revealed a conversion of 37% for the raw material benzyl methyl ether and a selectivity for methyl benzoate of 90%. Biphenyl was used as the internal standard.

[0165] 4. Performance Results

[0166] As can be seen from Examples 1-20, the present invention successfully prepared novel organic-inorganic hybrid materials coordinated with various organic acids and Mn- and Fe-containing hydrotalcites. Using green and economical molecular oxygen as the oxidant, the organic-inorganic hybrid material BA-Ni2Mg2Mn as the catalyst, and dodecane as the solvent, the catalytic synthesis of methyl benzylformate and its ester derivatives all achieved high yields. Substrate expansion experimental results (Table 1) demonstrate that the catalytic method of the present invention exhibits excellent substrate expansion.

[0167] Comparative Example 1 For Example 21, using Ni2Mg2Mn-LDH that is not coordinated with benzoic acid as a catalyst, it can be seen that the conversion rate of the reactant is reduced by 61% and the selectivity is reduced by 38%, indicating that the organic-inorganic hybrid material has obvious advantages in the yield and selectivity of methyl benzoate. In the present invention, the coordination environment of the cations in the organic-inorganic hybrid material changes, making the oxidizing ability of BA-Ni2Mg2Mn much stronger than that of Ni2Mg2Mn-LDH, resulting in efficient conversion of the reactant. After benzoic acid is coordinated with Ni2Mg2Mn-LDH, the surface acidity and alkalinity of the organic-inorganic hybrid material are regulated, so that the yield of the byproduct benzaldehyde is reduced; and the yield and selectivity of the target product are improved.

[0168] Comparative Example 2 For Example 21, air was used as the oxidant. It can be seen that the conversion rate of the reactant decreased by 58% and the selectivity decreased by 9%, indicating that molecular oxygen played a key role as an oxidant in the oxidation process. The concentration of oxygen in the air decreased, which weakened the oxidizing ability of BA-Ni2Mg2Mn in the reaction system, reduced the conversion rate of benzyl ether, and affected the conversion rate of the reactant.

[0169] The novel organic-inorganic hybrid catalytic material prepared in Example 1 was used as an example for relevant tests, wherein the XRD pattern is as follows Figure 1 As shown, according to Figure 1 XRD patterns of Figure 1 a shows that the prepared hydrotalcite-like material has typical diffraction peaks of hydrotalcite structure at 11.2°(003), 22.7°(006), 34.2°(009), 59.7°(110) and 61.0°(113), indicating that the hydrotalcite-like precursor was successfully prepared; Figure 1 b The result shows that the 003 diffraction surface disappears and a new diffraction peak appears at 18°. Figure 1 c, which is not the diffraction peak of benzoic acid, indicates that the novel organic-inorganic hybrid catalytic material BA-Ni2Mg2Mn involved in the present invention has a new crystal structure.

[0170] Its TG spectrum is as follows Figure 2 As shown, according to Figure 2 TG spectrum, Figure 2 b shows that the mass loss of BA-Ni2Mg2Mn is between that of BA and uncoordinated Ni2Mg2Mn-LDH, indicating that BA-Ni2Mg2Mn is not mixed with benzoic acid, but a chemical reaction occurs between the two.

[0171] Its SEM spectrum is as follows Figure 3 As shown, according to Figure 3 SEM images of Figure 3 a shows the layered structure of Ni2Mg2Mn-LDH, a typical hydrotalcite-like structure. Figure 3 b shows that in addition to the plate-like crystals, there are also columnar crystals on the surface of BA-Ni2Mg2Mn, indicating that a new crystal form is formed after the coordination of organic acid and hydrotalcite-like. Figure 1 The XRD results are consistent with those in .

[0172] Its FT-IR spectrum is as follows Figure 4 As shown, the results show that the COO - The asymmetric stretching vibration of the group is at 1686 cm -1 ( Figure 4 c) COO of BA-Ni2Mg2Mn - The asymmetric stretching vibration of the group is at 1597 cm -1 ( Figure 4 b), The shift of the corresponding peak in the infrared spectrum indicates that the coordination between benzoic acid and the metal cation of Ni2Mg2Mn-LDH forms a new organic-inorganic hybrid catalytic material. Figure 4 As shown in b, COO of BA-Ni2Mg2Mn - The asymmetric stretching vibration and symmetric stretching vibration of the group are 1597 cm -1 and 1419cm -1 , the difference is 178cm -1 , FT-IR spectrum Figure 4 COO of potassium benzoate shown in d - The asymmetric stretching vibration and symmetric stretching vibration of the group are 1552 cm -1 and 1416cm -1 , the difference is 136cm -1 , potassium benzoate COO - The difference between the asymmetric stretching vibration and the symmetric stretching vibration of the group is lower than that of BA-Ni2Mg2Mn, indicating that the coordination mode of benzoic acid in BA-Ni2Mg2Mn and the metal cation of Ni2Mg2Mn-LDH is monodentate coordination.

[0173] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. An application of an organic-inorganic hybrid catalytic material for the oxidation activation of α-CH bonds in aromatic side chains to prepare esters or ketones, characterized in that: The organic-inorganic hybrid catalytic material is prepared by coordinating an organic acid and a hydrotalcite-like metal cation in a solvent; The content of the hydrotalcite-like substance in the system is 25-100 g / L; the content of the organic acid in the system is 0.02-0.5 mol / L; The hydrotalcite-like compound is Ni2Mg2Mn-LDH, and the organic acid is any one of benzoic acid, 4-methoxybenzoic acid, 4-tert-butylbenzoic acid, 4-methylbenzoic acid, 4-fluorobenzoic acid, 4-chlorobenzoic acid, 4-bromobenzoic acid, 4-nitrobenzoic acid, n-butyric acid, n-pentanoic acid, n-hexanoic acid, adipic acid, and cyclohexylcarboxylic acid.

2. The use according to claim 1, characterized in that The carboxyl groups in the organic acid coordinate with the metal cations in the hydrotalcite-like substance.

3. The use according to claim 1, characterized in that The solvent is dodecane or diphenyl ether.

4. The use according to claim 1, characterized in that The steps of the preparation method of the organic-inorganic hybrid catalytic material are as follows: (1) Preparation of hydrotalcite-like S11: dissolving the desired metal salt in deionized water to form a mixed metal salt solution A; dissolving sodium carbonate in deionized water to form solution B; and dissolving sodium hydroxide in deionized water to form solution C; The molar concentration ratio of the three solutions is A: B: C = 2: 1: 6; S12: Add solution B to a four-necked round-bottom flask, and add solutions A and C dropwise to the four-necked round-bottom flask, controlling the pH value between 9 and 11. Stir continuously for 24 hours to form a suspension. S13: The formed suspension is washed with deionized water until neutral, filtered, and dried to obtain a hydrotalcite-like material; (2) Preparation of organic-inorganic hybrid catalytic materials S14: adding the prepared hydrotalcite-like substance, an organic acid and a solvent into a reactor to carry out a reaction. After the reaction is completed, the product is washed with ethyl acetate, filtered, and dried to obtain an organic-inorganic hybrid catalytic material.

5. The use according to claim 4, characterized in that In step S14, the synthesis temperature of the organic-inorganic hybrid catalytic material is 60-180°C.

6. The use according to claim 1, characterized in that The steps of the application are as follows: The compound shown in Formula I or Formula III is used as a reaction substrate, and the organic-inorganic hybrid catalytic material is added to a reactor; oxygen is used as an oxidant and introduced into the reactor for a catalytic reaction; after the reaction, the reaction solution is filtered, washed with ethyl acetate, and then distilled under reduced pressure and separated by column chromatography to obtain the target product of Formula II or target product IV; Where R 1 is any one of H, F, Cl, Br, methyl, methoxy, trifluoromethyl, tert-butyl, and nitro; R 2 Phenyl, C1~C 20 Any one of the alkyl groups; in formula III, R 3 is any one of H, F, Cl, Br, methyl, methoxy, trifluoromethyl, tert-butyl, and nitro; R 4 is phenyl or pyridyl.

7. The use according to claim 6, characterized in that The ratio of the organic-inorganic hybrid catalytic material to the reaction substrate is 10-100 g:1 mol.

8. The use according to claim 6, characterized in that The oxygen flow rate is 50 mL / min; the reaction temperature is 100~140℃; and the reaction time is 3~30 h.

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