Heteronuclear metal catalyst as well as synthesis method and application thereof

Abstract

The invention discloses a heteronuclear metal catalyst as well as a synthesis method and application thereof. The heteronuclear metal catalyst simultaneously has an electricity-rich M1 center and a high-valence M2 center, and is synthesized by taking M1 as a raw material, firstly carrying out coordination reaction with phosphorus atoms and then carrying out coordination reaction with nitrogen atoms by taking M2 (2X) as a raw material. The heteronuclear metal catalyst is applied to a regioselective functionalization reaction of an inert C (sp3)-H bond as a catalyst, and has the advantages of low catalyst loading capacity, small oxidant dosage and obvious improvement of reaction efficiency.

Description

Technical Field

[0001] The present invention belongs to the field of catalytic synthesis, and in particular relates to a heteronuclear metal catalyst and a synthesis method and application thereof. Background Art

[0002] For decades, inert C(sp 3 Direct functionalization of )-H bonds has always been regarded as the "holy grail" of organic chemistry. The selective introduction of valuable functional groups on alkyl groups has brought revolutionary potential to synthetic chemistry. This technology can be used as an efficient tool to help chemists play a role in the later diversification of drug compounds and the modification of advanced functional materials. However, harsh reaction conditions, dependence on directing groups and the need for highly active hydrogen atom transfer (HAT) reagents may limit the scope of substrate application and lead to unsatisfactory reaction efficiency and selectivity. Although significant progress has been made in the field of C-H bond functionalization, due to the high efficiency and selectivity of primary C(sp 3 )-H bond has inherent high bond dissociation energy, and its efficient and selective functionalization remains a difficult challenge, so there is an urgent need to develop efficient synthetic methods. In recent years, a large number of studies have been devoted to solving this fundamental problem (for related research, see Science 2024, 383, 537-544; Nat. Synth. 2024, 3, 537-544; J. Am. Chem. Soc. 2023, 145, 7600-7611; J. Am. Chem. Soc. 2023, 145, 15207-15217; Nat. (ommun. 2023, 14, 6530; Nature 2020, 586, 714-719; Science 2020, 368, 736-741; Science 2000, 287, 1995-1997), but these systems usually require harsh reaction conditions. In pursuit of sustainable and environmentally friendly chemical processes, researchers have developed a light-induced ligand-metal charge transfer (LMCT) strategy using earth-abundant transition metal catalysts; however, extending this LMCT method to intermolecular C(sp) under mild conditions is difficult. 3 )-H homolysis remains challenging because the process usually requires highly reactive HAT reagents and often exhibits low regioselectivity, resulting in complex product mixtures. Although the latest research has generated reactive chlorine radicals through the LMCT strategy to promote terminal methyl activation, exploring the primary C(sp 3 )-H bonds, but the reaction efficiency and regioselectivity still need to be further improved. Therefore, long-standing challenges such as high catalyst loading, reliance on stoichiometric oxidants, poor regioselectivity, and insufficient reaction efficiency remain a significant obstacle to the development of more practical systems. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a heteronuclear metal catalyst and its synthesis method and application. The heteronuclear metal catalyst has both an electron-rich M1 center and a high-valent M2 center, and is used as a catalyst in inert C (sp 3 )-H bond regioselective functionalization reaction, it can achieve the advantages of low catalyst loading, small amount of oxidant, and significantly improved reaction efficiency.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A heteronuclear metal catalyst, the structural formula of which is shown in Formula 1:

[0006]

[0007] in:

[0008] R 1 is methyl, ethyl, isopropyl, cyclopentyl, cyclohexyl, alkoxy or phenyl;

[0009] It is a nitrogen heterocycle such as pyridine, pyrazole, quinoline, imidazole, thiazole, pyrimidine, etc.

[0010] R 2 is a substituent on the nitrogen heterocyclic ring of hydrogen, fluorine, chlorine, bromine, iodine, methyl, ethyl, isopropyl, alkoxy, tert-butyl or phenyl;

[0011] X is fluorine, chlorine, bromine or iodine;

[0012] M1 is low-valent chromium, molybdenum, manganese, iron, cobalt, nickel, copper, silver or gold;

[0013] M2 is a high-valent state of chromium, molybdenum, manganese, iron, cobalt, nickel, copper, silver or gold.

[0014] Preferably, M1 is low-valent iron and M2 is high-valent chromium; or M1 is low-valent iron and M2 is high-valent iron.

[0015] The synthesis method of the heteronuclear metal catalyst is to use M1 as a raw material to first carry out a coordination reaction with a phosphorus atom, and then use M2 (2X) as a raw material to carry out a coordination reaction with a nitrogen atom to obtain the heteronuclear metal catalyst.

[0016] Specifically, the synthesis method of the heteronuclear metal catalyst comprises the following steps:

[0017] (1) 1-5 equivalents of a phosphorus nitrogen ligand (Structure 2) and 1 equivalent of M1 are placed in a reaction flask, a solvent is added, the reaction temperature is 20-80°C, and the reaction time is 4-48 hours; then, the reaction is concentrated under reduced pressure to obtain a mononuclear metal complex that is first coordinated with the phosphorus atom;

[0018] (2) One equivalent of a mononuclear metal complex and 1-5 equivalents of M2 (2X) are placed in a reaction flask, a solvent is added, the reaction temperature is 20-80°C, and the reaction time is 4-48 hours; then the reaction is concentrated under reduced pressure to obtain a heteronuclear metal catalyst.

[0019] In step (1), M1 may be preactivated or unactivated; the preactivation is to preactivate M1 with an imine compound.

[0020] In steps (1) and (2), the solvent is one or more of toluene, dichloromethane, tetrahydrofuran, acetonitrile, methanol, and ethanol.

[0021] The synthesis reaction formula of the above heteronuclear metal catalyst is as follows:

[0022]

[0023] The application of the heteronuclear metal catalyst is to be used as a catalyst in inert C (sp 3 )-H bond regioselective functionalization reaction.

[0024] More specifically, the inert C(sp 3 )-H bond regioselective functionalization reaction, comprising the following steps: sequentially adding 2-10 mol% of a heteronuclear metal catalyst (based on 1 equivalent of a boron source, mol% is calculated based on this), 50-100 mol% of a chloride salt, 50-100 mol% of an oxidant, 3 or more equivalents of an inert C (sp 3 )-H bond compound, 1 equivalent of boron source and solvent, irradiate with violet light at 0-50°C for 12-48 hours; then add pinacol (1-10 equivalents) or 1,8-diaminonaphthalene (1-10 equivalents) dissolved in triethylamine, and then separate and purify by column chromatography to obtain inert C(sp 3 )-H bond is functionalized.

[0025] The inert C(sp 3The )-H bond compound is a chain alkane or a chain alkane containing a substituent, silane, germane, or stannane. The solvent is toluene, dichloromethane, tetrahydrofuran, acetonitrile, methanol, or ethanol. The oxidant is dimethyl sulfoxide, N-fluorobisbenzenesulfonamide, diphenyl sulfoxide, N,N-dimethylacetamide, N,N-dimethylformamide, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, 1,4-naphthoquinone, p-benzoquinone, or anthraquinone. The chloride salt is tetraethylammonium chloride, tetrabutylammonium chloride, trimethylchlorosilane, lithium chloride, or hydrochloric acid. The boron source is bis(catechol) borate, pinacol borate, neopentyl glycol borate (bis(neopentyl glycol) diboron, hexanediol borate (bis(hexanediol) diboron), pinanediol borate (bis(pinenediol) diboron), pinacol borate-dansyl diboron or catechol borate (bis(catechol) diboron.

[0026] The heteronuclear metal catalyst of the present invention is applied to inert C(sp 3 The regioselective functionalization reaction of )-H bonds is based on the principle that a heteronuclear bimetallic catalyst incorporates an electron-rich, low-valent metal center (M1) as an electron donor, which synergistically acts with a high-valent metal center (M2) as a catalytic site. The heteronuclear bimetallic catalyst can be oxidized by an oxidant and, under light irradiation, interacts with chloride ions and a boron source (bis(bis-catechol boronate)) to form a heteronuclear catalyst intermediate that dissociates into carbon monoxide. In the MMLCT (metal-metal-ligand charge transfer) cycle, metal-metal charge transfer (MMCT) occurs due to the lower oxidation state metal center acting as an electron sink, promoting photoexcitation of the catalyst intermediate. This is followed by ligand-to-metal charge transfer (LMCT) to generate active chlorine radicals, which in turn promote a hydrogen atom transfer (HAT) process to produce alkyl radicals. In the MMLCT cycle, the bis(bis-catechol boronate) bound to the low-valent metal center of the heteronuclear bimetallic catalyst couples with alkyl radicals. Notably, the HAT process from alkanes to alkyl radicals is nonselective. We speculate that the high selectivity is due to the steric effect of the catalyst and substrate, which favors the preferential reaction of the terminal carbon radical with the boron moiety, leading to selective functionalization at the terminal position. Under the synergistic effect of the low-valent metal, the heteronuclear metal catalyst can undergo charge transfer between the boron moiety and the low-valent metal center. The catalyst then interacts with the chloride salt and bis(bis(diphenyl)benzene) boronate, regenerating for the next catalytic cycle. Due to the synergistic effect of the heterovalent bimetallic, this MMLCT cycle operates only with a catalytic amount of oxidant during the reaction, avoiding regeneration through oxidant oxidation. Furthermore, the products functionalized with the novel heteronuclear bimetallic catalyst can be further converted into a variety of products, such as cross-coupling, carbonylation, and hydroxylation.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The heteronuclear metal catalyst of the present invention integrates the charge-rich M1 center as an electron pool, and synergistically mediates the generation of chlorine radicals with the high-valent M2 center as a catalytic site, thereby achieving a selective and efficient terminal methyl functionalization reaction.

[0029] (2) Compared with the traditional LMCT strategy, the heteronuclear metal catalyst of the present invention can realize a significant metal-metal-ligand charge transfer (MMLCT) strategy, providing efficient and terminal methyl regioselective CH functionalization reactions for a variety of substrates including alkanes, silanes, and stannanes.

[0030] (3) For most substrates, the catalytic reaction of the catalyst of the present invention exhibits a specific terminal methyl regioselectivity (>95%), and the reaction efficiency is significantly improved. Taking the alkane substrate n-hexane as an example, the yield of functionalized product can reach 88%, while the terminal methyl regioselectivity C(sp 3 The corresponding yield of the )-H functionalization method (Science 2024, 383, 537-544) was 55%. In addition, compared with the literature method (Science 2024, 383, 537-544; which requires a 10 mol% catalyst loading and 1.4 equivalents of oxidant), the heteronuclear metal catalyst of the present invention only requires a low catalyst loading (2 mol%) and a catalytic amount of oxidant (50 mol%). BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the single crystal structure of catalyst 1 prepared in Example 1 (yellow: Fe; red: O, P; blue: N; gray: C; white: H; green: Br).

[0032] Figure 2 Schematic diagram of the single crystal structure of catalyst 2 prepared in Example 2 (yellow: Fe; red: Cr, O; green: Cl; blue: N; purple: P; gray: C; white: H). DETAILED DESCRIPTION

[0033] For ease of understanding of the present invention, the present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be pointed out that, for those skilled in the art, without departing from the inventive concept, the present invention can also make several variations and improvements, which all fall within the scope of protection of the present invention. The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial sources.

[0034] Example 1: Synthesis of Catalyst 1

[0035] (1) Add the raw material compound 1S (2.00 mmol), diphenylphosphine pyridine (2.00 mmol) and dichloromethane (1 mL) to a reaction flask, place the reaction flask at 30°C for 24 hours; then concentrate to dryness under reduced pressure to obtain compound 2S;

[0036]

[0037] (2) Compound 2S (1.00 mmol), ferrous bromide (1.00 mmol) and dichloromethane (1 mL) were added to a reaction flask and the reaction was carried out at 30°C for 12 hours. The catalyst 1 was then concentrated to dryness under reduced pressure to obtain the catalyst 1, the single crystal structure of which is shown in FIG. Figure 1 shown.

[0038]

[0039] Yield: 38%, 1 H NMR (400MHz, Chlorofom-d) δ8.19 (s, 16H), 7.85 (s, 2H), 7.50 (s, 2H), 7.38 (s, 8H). 13 C NMR (101MHz, Chloroform-d) δ213.65, 150.07, 150.00, 149.94, 139.39, 136.21, 1 33.90, 133.85, 133.80, 133.23, 130.18, 129.09, 128.31, 128.26, 128.21, 123.87. 31 P NMR (162MHz, Chloroform-d) δ84.17.IR (KBr, cm -1 ): 2004, 1942, 1920, 1871, 1580, 1484, 1459, 1435, 1422, 1090, 1002, 769, 741, 627, 575, 517.calculated forC 37 H 28 Br2Fe2N2O3P2: C, 50.38; H, 3.20; N, 3.18 found: C, 50.14; H, 3.54; N, 3.11

[0040]

[0041]

[0042] X-ray crystallography of catalyst 1 revealed that the low-valent Fe(0) center is stably anchored by the strong-field ligand CO and the phosphine ligand, exhibiting an octahedral coordination geometry. The Fe(0)-CO bond length is The Fe(0)-P bond length is Due to the strong reverse coordination of the low-valent Fe(0) center, the C≡O bond is elongated to The low-valent Fe(II) center is coordinated with pyridine and bromine ligands to form a trigonal bipyramidal geometry. Electron density Laplace analysis of compound 1 revealed the presence of a critical bond point between the Fe(0) and Fe(II) centers. Based on X-ray crystallography and electron density Laplace analysis, the Fe(0) and Fe(II) centers are connected by a bond of The bond lengths clearly present unique interactions, laying an optimal structural foundation for the subsequent metal-metal-ligand charge transfer (MMLCT) process.

[0043] Example 2: Synthesis of Catalyst 2

[0044] (1) Add the raw material compound 1S (2.00 mmol), diphenylphosphine pyridine (2.00 mmol) and dichloromethane (1 mL) to a reaction flask, place the reaction flask at 30°C for 24 hours; then concentrate under reduced pressure to dryness to obtain compound 2S;

[0045]

[0046] (2) Compound 2S (0.45 mmol), chromium chloride (0.45 mmol) and dichloromethane (1 mL) were added to a reaction flask, and the reaction was placed at 40°C for 12 hours. The catalyst 2 was then concentrated to dryness under reduced pressure to obtain the catalyst 2, the single crystal structure of which is shown in the following figure. Figure 2 shown.

[0047]

[0048] Yield: 34%, 1 H NMR (400MHz, Chloroform-d) δ8.76 (s, 2H), 8.08 (s, 3H), 7.74 (s, 10H), 7.41 (s, 13H). 31 P NMR (162MHz, Chloroform-d) δ84.04.

[0049]

[0050]

[0051] Example 3-6: Synthesis of Catalyst 3-6

[0052] <![CDATA[R 1 ]]> <![CDATA[R 2 ]]> X <![CDATA[M1]]> <![CDATA[M2]]> Catalyst 3 Cyclohexyl Pyridine chlorine Zero-valent iron Ferrous iron Catalyst 4 Phenyl 4-tert-Butylpyridine chlorine Zero-valent iron Nickel Catalyst 5 Phenyl Quinoline chlorine Zero-valent iron Cobalt (II) Catalyst 6 Phenyl Pyrazole chlorine Zero-valent iron Ferrous iron

[0053] The specific synthesis method is consistent with that of Examples 1 and 2.

[0054] The application examples of the heteronuclear metal catalyst of the present invention are as follows:

[0055] Example 7: Functionalization reaction to synthesize compound 7

[0056]

[0057] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system and purified to obtain compound 7 with a yield of 88% and terminal methyl regioselectivity (>95%).

[0058] The NMR data of compound 7 are as follows: 1 H NMR (400MHz, Chloroform-d) δ7.13-7.06 (m, 2H), 7.00 (dd, J=8.3, 1.1Hz, 2H), 6.30 ( dd, J=7.3, 1.0Hz, 2H), 5.60 (s, 2H), 1.45-1.27 (m, 8H), 0.89 (dt, J=18.0, 7.3Hz, 5H). 13 C NMR (101MHz, Chloroform-d) δ141.25, 136.34, 127.56, 119.56, 117.32, 105.39, 32.19, 31.77, 24.80, 22.63, 14.14. 11 B NMR (128MHz, Chloroform-d) δ31.59.

[0059] Example 8: Functionalization reaction to synthesize compound 8

[0060] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system, and the mixture was separated and purified by column chromatography to obtain compound 8 with a yield of 68% and terminal methyl regioselectivity (>95%).

[0061]

[0062] The NMR data of compound 8 are as follows: 1 H NMR (400MHz, Chloroform-d) δ7.10 (dd, J=8.3, 7.3Hz, 2H), 7.01 (dd, J=8.3, 1.0Hz, 2H), 6.30 (dd, J=7.3, 1.0Hz, 2 H), 5.61 (s, 2H), 1.49-1.40 (m, 2H), 1.29 (td, J=9.7, 7.7, 4.3Hz, 10H), 0.92-0.88 (m, 3H), 0.85 (d, J=8.0Hz, 2H). 13 C NMR (101MHz, Chloroform-d) δ141.37, 136.46, 127.68, 119.68, 117-44, 105.51, 32.66, 32.08, 29.65, 29-43, 24.96, 22.84, 14.27. 11 B NMR (128MHz, Chloroform-d) δ32.54.

[0063] Example 9: Functionalization reaction to synthesize compound 9

[0064] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system, and the mixture was separated and purified by column chromatography to obtain compound 9 with a yield of 64% and terminal methyl regioselectivity (>95%).

[0065]

[0066] The NMR data of compound 9 are as follows: 1 H NMR (400MHz, Chloroform-d) δ1.77 (dt, J=13.7, 7.0Hz, 1H), 1.62 (dd, J=13.3, 6.7Hz, 1H), 1.24 (s, 12 H), 1.09-1.03 (m, 2H), 0.90-0.84 (m, 9H), 0.80 (dd, J=14.1, 4.7Hz, 1H), 0.62 (dd, J=15.3, 8.3Hz, 1H). 13 C NMR (101MHz, Chloroform-d) δ82.80, 49.40, 27.07, 25.47, 24.87, 24.82, 23.30, 22.47. 11 B NMR (128MHz, Chloroform-d) δ34.02.

[0067] Example 10: Functionalization reaction to synthesize compound 10

[0068] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system, and the mixture was separated and purified by column chromatography to obtain compound 10 with a yield of 76% and terminal methyl regioselectivity (>95%).

[0069]

[0070] The NMR data of compound 10 are as follows: 1 H NMR (400MHz, Chloroform-d) δ1.24 (s, 12H), 0.09 (s, 6H), 0.07 (s, 2H), 0.05 (s, 9H). 13 C NMR (101MHz, Chloroform-d) δ82.88, 25.16, -2.19, -2.28. 11 B NMR (128MHz, Chloroform-d) δ33.76.

[0071] Example 11: Functionalization reaction to synthesize compound 11

[0072] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system, and the mixture was separated and purified by column chromatography to obtain compound 11 with a yield of 70% and terminal methyl regioselectivity (>95%).

[0073]

[0074] The NMR data of compound 11 are as follows: 1 H NMR (400MHz, Chloroform-d) δ7.54 (q, J=7-4Hz, 4H), 1.20 (s, 12H), 0.37 (s, 2H), 0-35 (s, 6H), 0.27 (s, 9H). 13 C NMR (101MHz, Chloroform-d) δ141.08, 140.83, 132.85, 132.66, 82.96, 25.03, -0.85, -1.06. 11 B NMR (128MHz, Chloroform-d) δ34.27.

[0075] Example 12: Functionalization reaction to synthesize compound 12

[0076] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system, and the mixture was separated and purified by column chromatography to obtain compound 12 with a yield of 65% and terminal methyl regioselectivity (>95%).

[0077]

[0078] The NMR data of compound 12 are as follows: 1 H NMR (400MHz, Chloroform-d) δ1.23 (s, 12H), 0.21 (s, 2H), 0.15 (s, 9H). 13 C NMR (101MHz, Chloroform-d) δ82.56, 24.97, -8.54. 11 B NMR (128MHz, Chloroform-d) δ34.20.

[0079] Example 13: Functionalization reaction to synthesize compound 13

[0080] Catalyst 1 (2 mol%, 0.004 mmol), tetrabutylammonium chloride (TEACl) (50 mol%, 0.1 mmol), N-fluorobisbenzenesulfonamide (NFSI) (50 mol%, 0.1 mmol), compound 1a (bis(bis-catechol) borate) (1.0 eq., 0.2 mmol), n-hexane (20.0 eq., 4.0 mmol), and dichloromethane (dry DCM) (2 mL) were added to the reaction flask in sequence. The reaction flask was placed under violet light at 27°C for 24 hours. 1,8-diaminonaphthalene (2.0 mmol) dissolved in 1 mL of triethylamine was added to the system, and the mixture was separated and purified by column chromatography to obtain compound 13 with a yield of 29% and terminal methyl regioselectivity (>95%).

[0081]

[0082] The NMR data of compound 13 are as follows: 1H NMR (400MHz, Chloroform-d) δ7.28 (d, J=4.8Hz, 2H), 7.23 (s, 2H), 7.16 (d, J=6.9Hz, 1H), 2.75 (t, J=8.2Hz, 2H), 1.29-1.25 (m, 3H), 1.22 (s, 12H), 1.15 (t, J=8.2Hz, 2H). 13 C NMR (101MHz, Chloroform-d) δ132.62, 128-33, 128.14, 125.64, 83.24, 30.09, 24.95. 11 B NMR (128MHz, Chlorofom-d) δ34.09.

[0083] Comparative Example:

[0084] The heteronuclear metal catalyst of the present invention exhibits a specific terminal methyl regioselectivity (>95%) for most substrates, which is rarely reported in related studies. Moreover, the catalytic reaction efficiency of the present invention is significantly improved, far higher than that of previously reported systems. Taking the simple alkane substrate n-hexane as an example, the functionalized product yield of the present invention can reach 88%, while the terminal methyl regioselectivity C (sp 3 The corresponding yield of the )-H functionalization method (Science 2024, 383, 537-544) was 55%. Furthermore, compared to the literature method (Science 2024, 383, 537-544; which requires a 10 mol% catalyst loading and 1-4 equivalents of oxidant), the heteronuclear metal catalyst of the present invention requires only a low catalyst loading (2 mol%) and a catalytic amount of oxidant (50 mol%). The yield of the present invention is also improved compared to that reported in a recent article (J. Am. Chem. Soc. 2023, 145, 7600-7611).

[0085] See the table below for specific comparison.

[0086]

[0087] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Ordinary technicians in this field should understand that the present invention can still be partially modified or replaced with equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the scope of protection of the present invention.

Claims

1. A heteronuclear metal catalyst, characterized in that: The structural formula is shown in Formula 1: in: R 1 is methyl, ethyl, isopropyl, cyclopentyl, cyclohexyl, alkoxy or phenyl; It is a nitrogen heterocycle such as pyridine, pyrazole, quinoline, imidazole, thiazole, pyrimidine, etc. R 2 is a substituent on the nitrogen heterocyclic ring of hydrogen, fluorine, chlorine, bromine, iodine, methyl, ethyl, isopropyl, alkoxy, tert-butyl or phenyl; X is fluorine, chlorine, bromine or iodine; M1 is low-valent chromium, molybdenum, manganese, iron, cobalt, nickel, copper, silver or gold; M2 is a high-valent state of chromium, molybdenum, manganese, iron, cobalt, nickel, copper, silver or gold.

2. The heteronuclear metal catalyst according to claim 1, characterized in that: M1 is low-valent iron and M2 is high-valent chromium; or M1 is low-valent iron and M2 is high-valent iron.

3. A method for synthesizing the heteronuclear metal catalyst according to claim 1 or 2, characterized in that: M1 is used as a raw material to first undergo coordination reaction with a phosphorus atom, and then M2 (2X) is used as a raw material to undergo coordination reaction with a nitrogen atom to obtain a heteronuclear metal catalyst.

4. The method for synthesizing a heteronuclear metal catalyst according to claim 3, wherein: The steps include: (1) placing 1-5 equivalents of a phosphorus nitrogen ligand and 1 equivalent of M1 in a reaction flask, adding a solvent, and reacting at a temperature of 20-80° C. for 4-48 hours; then concentrating under reduced pressure to obtain a mononuclear metal complex that is first coordinated with the phosphorus atom; (2) One equivalent of a mononuclear metal complex and 1-5 equivalents of M2 (2X) are placed in a reaction flask, a solvent is added, the reaction temperature is 20-80°C, and the reaction time is 4-48 hours; then the reaction is concentrated under reduced pressure to obtain a heteronuclear metal catalyst.

5. The method for synthesizing a heteronuclear metal catalyst according to claim 4, wherein: In step (1), M1 may be preactivated or unactivated; the preactivation is to preactivate M1 with an imine compound.

6. The method for synthesizing a heteronuclear metal catalyst according to claim 4, wherein: In steps (1) and (2), the solvent is one or more of toluene, dichloromethane, tetrahydrofuran, acetonitrile, methanol, and ethanol.

7. Use of the heteronuclear metal catalyst according to claim 1 or 2, characterized in that: It is used as a catalyst in inert C(sp 3 )-H bond regioselective functionalization reaction.

8. The use of the heteronuclear metal catalyst according to claim 7, characterized in that: The method comprises the following steps: sequentially adding 2-10 mol% of a heteronuclear metal catalyst, 50-100 mol% of a chloride salt, 50-100 mol% of an oxidant, 3 equivalents or more of an inert C(sp 3 )-H bond compound, 1 equivalent of boron source and solvent, irradiate with violet light at 0-50°C for 12-48 hours; then add 1-10 equivalents of pinacol or 1,8-diaminonaphthalene dissolved in triethylamine, and then separate and purify by column chromatography to obtain inert C(sp 3 )-H bond is functionalized.

9. The use of the heteronuclear metal catalyst according to claim 8, characterized in that: The inert C(sp 3 The )-H bond compound is a chain alkane, silane, germane or stannane; the solvent is toluene, dichloromethane, tetrahydrofuran, acetonitrile, methanol or ethanol; the oxidant is dimethyl sulfoxide, N-fluorobisbenzenesulfonamide, diphenyl sulfoxide, N,N-dimethylacetamide, N,N-dimethylformamide, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, 1,4-naphthoquinone, p-benzoquinone or anthraquinone; the chloride salt is tetraethylammonium chloride, tetrabutylammonium chloride, trimethylchlorosilane, lithium chloride or hydrochloric acid.

10. The use of the heteronuclear metal catalyst according to claim 8, characterized in that: The boron source is bis(catechol) borate, pinacol borate, neopentyl glycol borate (bis(neopentyl glycol) diboron, hexanediol borate (bis(hexanediol) diboron), pinanediol borate (bis(pinenediol) diboron), pinacol borate-dansyl diboron or catechol borate (bis(catechol) diboron.

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