Catalytic method for preparing 1, 2-diphosphonoethane compound through neutral photocatalysis

Abstract

The invention belongs to the technical field of catalytic methods and catalysts, and particularly relates to a catalytic method for preparing a 1, 2-diphosphonoethane compound through neutral photocatalysis, which realizes efficient conversion of preparing a 1, 2-diphosphonoethane derivative through alkyne diphosphonation by taking diphenyl phosphine oxide as a phosphine source under a neutral photocatalysis condition. The method comprises the following steps: carrying out two-time free radical addition reaction on alkyne through diphenyl phosphine oxide; a reaction system is simple and clean, no extra acid-base or other additives are used, and the method can be efficiently carried out under mild room-temperature and normal-pressure conditions; according to the present invention, the method has characteristics of high yield and good chemical selectivity, the reaction substrate range is wide, the reaction condition is mild, the simple and easily available substrate raw material is adopted, the use of the complex substrate is avoided, the obtained product can be further derivatized into a variety of diphosphine ligands, and the good application prospects are provided in the fields of catalytic chemistry, material science and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of catalytic methods and catalysts, and specifically relates to a catalytic method for preparing 1,2-bisphosphonylethane compounds by neutral photocatalysis. Background Art

[0002] 1,2-Bisphosphonates are an important class of organic phosphine compounds. Their molecular structure contains two phosphonyl groups (-PO 3 R 2 ) are connected by ethane bridges. Due to their unique chemical properties, these compounds have shown important application value in many fields. In the medical field, they are used as drugs or drug intermediates, and have the effects of treating osteoporosis, anti-tumor and targeted radiotherapy. In the industrial field, they are used as metal ligands or flame retardant materials. In the material field, they are used to prepare metal-organic frameworks or surface modification materials, and are also used in pesticides and fertilizer enhancers.

[0003] At present, the synthesis methods of 1,2-bisphosphonylethane compounds include: (1) Michaelis-Arbuzov reaction; (2) nucleophilic substitution reaction; (3) transition metal catalytic coupling; however, the Michaelis-Arbuzov reaction is prone to generate monosubstituted by-products, and excessive phosphating may occur during nucleophilic substitution. In addition, the above-mentioned synthesis methods usually use dihaloethane, ethylene oxide, etc. as initial raw materials and are prepared through multiple steps of reaction, or are prepared using alkenyl phosphine and metal, strong base and high temperature catalysis. These conditions have problems such as high raw material toxicity, metal catalyst residue, and overly harsh reaction conditions.

[0004] In order to solve the above technical problems, the present invention uses a new catalytic method that is milder and more environmentally friendly, uses readily available alkynes as substrates to efficiently synthesize 1,2-bisphosphonylethane compounds, and the new catalytic method based on low-dose photocatalyst photocatalysis using alkynes as raw materials to synthesize 1,2-bisphosphonylethane compounds in one step has the advantages of energy saving and environmental protection, and has great application potential. Summary of the invention

[0005] The object of the present invention is to provide a catalytic method for preparing 1,2-bisphosphonylethane compounds by neutral photocatalysis, comprising the following steps:

[0006] Wherein, R is a full carbon alkyl group or an alkyl group containing one or more of an aromatic ring, a heteroaromatic ring, a carboxylic acid, an ester group, an amide, an ether and a primary alcohol; (1) Under argon environment, add alkyne compounds, diphenylphosphine oxide and photocatalyst into a Schlenk reaction tube, and add solvent; (2) stirring the reaction mixture at room temperature under visible light until the alkyne compound added in step (1) is completely reacted; (3) After the reaction is completed, the aqueous phase is extracted, the organic phases are combined, washed, and dried, and the organic phase is concentrated under reduced pressure and filtered through a silica gel column to obtain the target product.

[0007] Preferably, the solvent in step (1) is any one of dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone, acetonitrile, tetrahydrofuran, toluene, 1,2-dichloroethane and isopropanol.

[0008] Preferably, the solvent in step (1) is any one of acetonitrile, tetrahydrofuran, dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone and toluene.

[0009] Preferably, the photocatalyst in step (1) is 4CzIPN, 4DPAIPN, [Ir(dtbbpy)(ppy) 2 ]PF 6 、Ru(bpy) 3 (PF 6 ) 2 、Ir(ppy) 3 and [Mes-Acr-Ph] + (Cl) - Any of .

[0010] Preferably, the photocatalyst in step (1) is 4CzIPN, 4DPAIPN and Ir(ppy) 3 Any of .

[0011] Preferably, the visible light in step (2) is 430-460 nm blue light, and the light source power is 1-100 W.

[0012] Preferably, the stirring time in step (2) is 24-36 hours.

[0013] Preferably, ethyl acetate is used for extraction in step (3), and saturated brine is used for washing.

[0014] Preferably, the drying in step (3) uses anhydrous Na 2 SO 4 .

[0015] Preferably, in the silica gel column described in step (3), PE:EA=1:1-1:3.

[0016] The beneficial effects of the present invention are as follows: In summary, the present invention provides a method for preparing 1,2-bisphosphonylethane compounds by neutral photocatalytic diphosphination of alkynes. The method uses diphenylphosphine oxide as a phosphine source under neutral photocatalytic conditions to achieve efficient conversion of alkyne diphosphination to prepare 1,2-bisphosphonylethane derivatives, and is a reaction of two free radical additions of diphenylphosphine oxide to alkynes; the reaction system is simple and clean, and no additional acid, alkali or other additives are used, and it can be carried out efficiently under mild room temperature and atmospheric pressure conditions; it has high yield and good chemical selectivity, and the reaction substrate range of the present invention is wide, and various functional groups such as methyl, methoxy, phenyl, and halogen are compatible with the reaction; the reaction conditions are mild, and starting from simple and easily available substrate raw materials, the use of complex substrates is avoided, and 1,2-bisphosphonylethane compounds with potential application value can be directly synthesized from commercial alkynes with good to excellent yields. The obtained products can be further derivatized into various diphosphine ligands, showing good application prospects in the fields of catalytic chemistry and materials science. DETAILED DESCRIPTION

[0017] The protection scope of the present invention is further illustrated below through specific embodiments, but this should not be understood as the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies implemented based on the above content of the present invention belong to the scope of the present invention.

[0018] It should be noted that, in the following examples, unless otherwise specified, the methods described are conventional methods and the reagents described can be purchased from commercial sources.

[0019] In the following examples, the 4CzIPN is a typical thermally activated delayed fluorescence (TADF) material, which realizes efficient reverse intersystem crossing (RISC) through a strong donor-acceptor (DA) structure of carbazole (Cz) and cyano (CN).

[0020] In the following examples, the [Ir(dtbbpy)(ppy) 2 ]PF 6 It is an important cationic iridium (III) complex, which is widely used in organic optoelectronic materials (such as OLED, photocatalysis, bioimaging) and photochemical research (such as photosensitization, photoredox catalysis).

[0021] In the following examples, the Ir(ppy) 3 It is tris(2-phenylpyridine)iridium and participates in the photoinduced electron transfer reaction as a photocatalyst.

[0022] In the following embodiments, the 4DPAIPN, whose full name is 2,4,5,6-Tetra(diphenylamino)isophthalonitrile, can be used as a photocatalyst.

[0023] In the following examples, the [Mes-Acr-Ph]⁺(Cl)⁻, whose full name is 9-Mesityl-10-phenylacridinium chloride, can be used as a photocatalyst.

[0024] In the following examples, the Ru(bpy) 3 (PF 6 ) 2 It is a classic ruthenium (II) complex, the full name of which is tris (2,2'-bipyridyl) ruthenium (II) hexafluorophosphate (*Tris (2,2'-bipyridyl) ruthenium (II) hexafluorophosphate*), and is one of the most important photocatalysts in photochemical and electrochemical research.

[0025] In the following examples, the Schlenk tube is a laboratory glass instrument designed for anhydrous and oxygen-free operations and is widely used in chemical reactions that are sensitive to air / moisture (such as organometallic synthesis, transition metal catalysis, free radical reactions, etc.).

[0026] Example 1

[0027] 1,2-Bisphosphonylethane compounds were prepared from 4-phenyl-1-butyne and diphenylphosphine oxide.

[0028]

[0029] Under argon atmosphere, 4-phenyl-1-butyne 1a (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1a disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3aa.

[0030] The product testing data are as follows: Colorless colloid, yield 76%.

[0031] 1 H NMR (400 MHz, CDCl 3 ) δ 7.79 – 7.64 (m, 6H), 7.58 (dd, J = 11.1, 7.8Hz, 2H), 7.53 – 7.30 (m, 12H), 7.07 (t, J = 7.8 Hz, 2H), 6.82 (t, J = 7.3 Hz,1H), 6.36 (d, J = 8.1 Hz, 2H), 4.37 (ddd, J = 17.4, 9.9, 3.7 Hz, 1H), 4.17 – 4.04(m, 1H), 3.44 (dd, J = 8.5, 5.0 Hz, 1H), 2.79 – 2.62 (m, 2H). 13 C NMR (100 MHz, CDCl 3 ) δ 141.30 (s), 133.03 (d, J = 97 Hz), 132.80(d, J =99.5 Hz), 132.48(d, J = 2.9 Hz), 131.62(d, J = 95.6 Hz), 131.32(d, J = 132.8 Hz),133.85(d, J = 2.8 Hz), 131.75(t, J = 3.5 Hz), 130.97 (dd, J = 8.8, 3.5 Hz), 130.59(dd, J = 9.3, 6.5 Hz), 128.91 – 128.49 (m), 128.08 (d, J = 21.5 Hz), 125.55 (s), 33.26 (d, J = 4.4 Hz), 31.08 (dd, J = 69.1, 3.8 Hz), 30.29 (s), 27.38 (d, J= 69.0Hz). 31 P NMR (162 MHz, CDCl3) δ 34.84 (s), 31.62 – 30.40 (m).

[0032] Example 2 1,2-Bisphosphonylethane compounds were prepared from 2,2-dimethylpropionic acid but-3-yn-1-yl ester and diphenylphosphine oxide.

[0033]

[0034] Under argon atmosphere, 2,2-dimethylpropionic acid but-3-yn-1-yl ester 1b (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1b disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3ba.

[0035] The product testing data are as follows: White amorphous solid, yield 82%.

[0036] 1 H NMR (400 MHz, CDCl 3 ) δ 7.79 – 7.62 (m, 6H), 7.55 – 7.30 (m, 14H), 3.90–3.79 (m, 2H), 3.03 (dt, J = 15.2, 8.0 Hz, 1H), 2.67 – 2.45 (m, 2H), 2.21 –2.05 (m, 1H), 2.05 – 1.91 (m, 1H), 1.04 (s, 9H).

[0037] 13 C NMR (100 MHz, CDCl 3 ) δ 177.59 (s), 133.01 (d, J = 100.4 Hz), 132.70(s), 131.19 (d, J= 97.8 Hz), 131.86 (ddd, J = 11.3, 10.0, 2.9 Hz), 130.76 (ddd, J = 28.0, 17.2, 9.0 Hz), 130.70 (s), 128.76 (d, J = 2.5 Hz), 128.75 (d, J = 21.5Hz), 128.74 (d, J = 2.5 Hz), 128.65 (d, J = 13.0 Hz), 61.60 (d, J = 6.2 Hz), 38.36(s), 28.48 (dd, J = 69.6, 4.0 Hz), 28.12 (d, J = 68.5 Hz), 27.89 (d, J = 2.1 Hz),27.04 (s).

[0038] 31 P NMR (162 MHz, CDCl 3 ) δ 36.37 (d, J = 44.7 Hz), 30.15 (dd, J = 45.2,11.0 Hz).

[0039] Example 3 1,2-Bisphosphonylethane compounds were prepared from 2,2-dimethylpropionic acid but-3-yn-1-yl ester and diphenylphosphine oxide.

[0040]

[0041] Under argon atmosphere, 2,2-dimethylpropionic acid but-3-yn-1-yl ester 1c (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1c disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3ca.

[0042] The product testing data are as follows: White amorphous solid, yield 74%.

[0043] 1 H NMR (400 MHz, CDCl 3 ) δ 7.78 – 7.63 (m, 7H), 7.53 – 7.30 (m, 15H),7.21 (t, J = 7.6 Hz, 1H), 7.04 (d, J = 8.1 Hz, 1H), 3.82 – 3.71 (m, 2H), 3.01(dd, J = 16.1, 13.0 Hz, 1H), 2.70 – 2.60 (m, 1H), 2.53 (dd, J = 27.2, 13.6 Hz,1H), 2.29 (s, 3H), 1.95 – 1.80 (m, 2H), 1.68 – 1.54 (m, 1H), 1.54 – 1.41 (m,1H). 13 C NMR (100 MHz, CDCl 3 ) δ 169.57 (s), 163.69 (s), 150.63 (s), 133.57(s), 132.98 (d, J = 98.5 Hz), 132.55 (d, J = 100.8 Hz), 131.92 (s), 131.84 –131.67 (m), 131.61 (s), 130.77 (dd, J = 18.6, 9.3 Hz), 130.47 (dd, J = 9.3, 2.1Hz), 125.71 (s), 123.58 (s), 122.89 (s), 64.52 (s), 30.83 (dd, J = 69.2, 3.9Hz), 26.91 (d, J = 68.7 Hz), 25.76 (d, J = 4.6 Hz), 24.70 (d, J = 1.8 Hz), 20.93(s). 31 P NMR (162 MHz, CDCl3 ) δ 36.85 (d, J = 40.5 Hz), 30.14 (ddd, J = 47.1,23.5, 11.8 Hz).

[0044] Example 4 1,2-Bisphosphonylethane compounds were prepared from 2-chloropyridine-3-carboxylic acid but-3-yn-1-yl ester and diphenylphosphine oxide.

[0045]

[0046] Under argon atmosphere, 2-chloropyridine-3-carboxylic acid but-3-yn-1-yl ester 1d (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1d disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3da.

[0047] The product testing data are as follows: White amorphous solid, yield 51%.

[0048] 1 H NMR (400 MHz, CDCl 3 ) δ 8.47 (dd, J = 4.7, 1.8 Hz, 1H), 8.10 (dd, J =7.7, 1.8 Hz, 1H), 7.76 – 7.58 (m, 6H), 7.51 – 7.30 (m, 14H), 7.29 – 7.26 (m,1H), 4.33 – 4.23 (m, 1H), 4.23 – 4.14 (m, 1H), 3.10 – 2.97 (m, 1H), 2.63 –2.53 (m, 2H), 2.41 – 2.26 (m, 1H), 2.24 – 2.11 (m, 1H). 13 C NMR (100 MHz, CDCl 3) δ 163.68 (s), 151.61 (s), 149.72 (s), 140.60 (s), 132.95 (d, J = 99.4 Hz), 131.81 (d, J = 88.9 Hz), 132.08 – 131.76 (m), 131.33 (d, J = 11.6 Hz), 131.02 (d, J = 96.8 Hz), 131.00 – 130.67 (m), 130.39 (d, J = 9.1 Hz), 128.88 (s), 128.75 (t, J = 2.0 Hz), 128.63 (d, J = 1.8 Hz), 126.82(s), 122.00 (s), 63.46 (d, J = 6.1 Hz), 28.90 (dd, J = 69.0, 4.0 Hz), 28.08 (d, J =68.4 Hz), 27.63 (d, J = 2.1 Hz). 31 P NMR (162 MHz, CDCl 3 ) δ 36.32 (d, J = 38.3 Hz), 30.64 (ddd, J = 35.9,24.5, 12.1 Hz).

[0049] Example 5 1,2-Bisphosphonylethane compounds were prepared using pent-4-ynoic acid and diphenylphosphine oxide as raw materials.

[0050]

[0051] Under argon atmosphere, pent-4-ynoic acid 1e (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1e disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:3) to obtain the target product 3ea.

[0052] The product testing data are as follows: White amorphous solid, yield 79%.

[0053] 1 H NMR (400 MHz, CDCl 3 ) δ 7.74 (dd, J = 10.4, 7.7 Hz, 2H), 7.64 (ddd, J =14.6, 12.6, 9.6 Hz, 4H), 7.53 – 7.31 (m, 14H), 3.01 – 2.84 (m, 1H), 2.73 –2.54 (m, 2H), 2.45 (t, J = 7.6 Hz, 2H), 2.32 – 2.14 (m, 1H), 2.01 – 1.84 (m,1H). 13 C NMR (100 MHz, CDCl 3 ) δ 174.34 (s), 132.14 (d, J = 102.0 Hz), 132.07(dd, J = 39.1, 2.5 Hz), 132.07 (d, J = 2.8 Hz), 131.40 (s), 131.07 (s), 130.91(dd, J = 14.0, 4.5 Hz), 130.68 (d, J = 48.6 Hz), 130.54 (s), 130.09 (d, J = 5.2Hz), 128.85 (dd, J = 11.9, 2.4 Hz), 31.81 (d, J = 7.0 Hz), 30.53 (dd, J = 68.3, 3.9Hz), 27.31 (d, J = 68.3 Hz), 24.52 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 37.58 (s), 34.25 – 32.38 (m).

[0054] Example 6 Acid but-3-yn-1-yl ester and diphenylphosphine oxide are used as raw materials to prepare 1,2-bisphosphonylethane compounds.

[0055]

[0056] Under argon atmosphere, cyclobutanecarboxylic acid but-3-yn-1-yl ester 1f (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1f disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3fa.

[0057] The product testing data are as follows: White amorphous solid, yield 48%.

[0058] 1 H NMR (400 MHz, CDCl 3 ) δ 7.79 – 7.64 (m, 6H), 7.53 – 7.35 (m, 14H), 3.91 (qt, J = 11.2, 7.0 Hz, 2H), 3.08 – 2.88 (m, 2H), 2.65 – 2.49 (m, 2H), 2.22– 2.03 (m, 5H), 1.98 (dt, J = 11.7, 6.3 Hz, 1H), 1.94 – 1.86 (m, 1H), 1.86 –1.75 (m, 1H). 13 C NMR (100 MHz, CDCl 3 ) δ 174.65 (s), 133.05 (d, J = 100.1 Hz), 132.23(d, J = 97.3 Hz), 131.88 (dd, J = 23.4, 2.7 Hz), 131.90 (t, J= 3.3 Hz), 131.72 (d, J = 3.0 Hz), 130.96 (dd, J = 12.6, 9.5 Hz), 130.68 (dd, J = 20.4, 7.9 Hz), 128.77(d, J = 23.1 Hz), 128.73 (s), 128.69 (d, J = 16.6 Hz), 61.61 (d, J = 6.2 Hz), 37.85(s), 28.65 (dd, J = 69.4, 4.1 Hz), 28.01 (d, J = 67.2 Hz), 27.79 (d, J = 1.8 Hz), 25.10 (s), 18.30 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 36.39 (s), 30.34 (ddd, J = 36.2, 25.0, 12.6 Hz).

[0059] Example 7 1,2-Bisphosphonylethane compounds were prepared from 4-chlorobenzoic acid but-3-yn-1-yl ester and diphenylphosphine oxide.

[0060]

[0061] Under argon atmosphere, 1 g (0.2 mmol) of 4-chlorobenzoic acid but-3-yn-1-yl ester, diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until 1 g of the raw material disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate 3 times, the organic phases were combined, and the organic phases were washed 3 times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3ga.

[0062] The product testing data are as follows: White amorphous solid, yield 59%.

[0063] 1 1H NMR (400 MHz, CDCl3) δ 7.86 - 7.79 (d, J J = 34.6, 2H), 7.79 – 7.63 (m,6H), 7.55 – 7.43 (m, 6H), 7.43 - 7.34(m, 10H), 4.26 – 4.09 (m, 2H), 3.16 – 3.03(m, 1H), 2.70 – 2.53 (m, 2H), 2.43 – 2.29 (m, 1H), 2.24 - 2.10 (m, 1H). 13 13C NMR (100 MHz, CDCl 3 ) δ 164.96 (s), 139.09 (s), 132.55 (s), 132.11– 131.77 (m), 131.58 (d, J J = 2.5 Hz), 131.18 (d, J J = 96.7 Hz), 131.58 (d, J J = 2.5Hz), 130.99 (d, J J = 9.0 Hz), 130.96 (s), 130.86 (dd, J J = 9.0, 2.4 Hz), 130.51 (d, J J = 9.3 Hz), 128.83 (d, J J = 2.8 Hz), 128.82 (d, J J = 21.5 Hz), 128.77 (d, J J = 1.7Hz), 128.67 (d, J J = 1.5 Hz), 128.51 (s), 62.51 (d, J J = 5.9 Hz), 28.90 (dd, J J =69.2, 4.2 Hz), 28.07 (d, J J = 69.1 Hz), 27.84 (s). 31 31P NMR (162 MHz, CDCl 3 ) δ 36.19 (s), 31.45 – 29.28 (m).

[0064] Example 8 1,2-Bisphosphonylethane compounds were prepared using 4-(trifluoromethyl)benzoic acid but-3-yn-1-yl ester and diphenylphosphine oxide as raw materials.

[0065]

[0066] Under argon atmosphere, 4-(trifluoromethyl)benzoic acid but-3-yn-1-yl ester 1h (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h under 12 W 460 nm LED blue light at room temperature until the raw material 1h disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate 3 times, the organic phases were combined and washed with saturated brine 3 times, and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE: EA = 1:1-1:3) to obtain the target product 3ha.

[0067] The product testing data are as follows: White amorphous solid, yield 73%.

[0068] 1 H NMR (400 MHz, CDCl 3 ) δ 8.00 (d, J = 8.1 Hz, 2H), 7.70 (ddd, J = 30.1,14.7, 8.4 Hz, 8H), 7.54 – 7.31 (m, 14H), 4.29 – 4.12 (m, 2H), 3.08 (dd, J =11.5, 6.7 Hz, 1H), 2.70 – 2.53 (m, 2H), 2.43 – 2.32 (m, 1H), 2.25 – 2.12 (m,1H). 13 C NMR (100 MHz, CDCl 3 ) δ 164.63 (s), 134.12 (dd, J = 65.2, 32.6 Hz), 132.98 (dd, J = 86.6, 2.0 Hz), 132.13 – 131.74 (m), 131.67 (s), 131.53 (d, J =2.4 Hz), 131.16 (d, J= 9.9 Hz), 130.99 (d, J = 8.6 Hz), 130.83 (dd, J = 9.0, 3.9Hz), 130.64 (d, J = 15.7 Hz), 130.48 (d, J = 9.4 Hz), 129.95 (s), 128.84 (dd, J =12.1, 8.8 Hz), 128.71 (dd, J = 10.4, 1.8 Hz), 128.52 (d, J = 12.1 Hz) 125.19 (q, J = 3.7 Hz), 124.97 (s), 122.26 (s), 62.86 (d, J = 5.8 Hz), 28.95 (dd, J = 69.0,4.0 Hz), 27.96 (d, J = 68.3 Hz), 27.73 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 36.14 (s), 30.43 (ddd, J = 36.4, 24.7, 12.7 Hz). 19 F NMR (377 MHz, CDCl 3 ) δ -63.01 (s).

[0069] Example 9 1,2-Bisphosphonylethane compounds were prepared from 4-methoxybenzoic acid but-3-yn-1-yl ester and diphenylphosphine oxide.

[0070]

[0071] Under argon atmosphere, 4-methoxybenzoic acid but-3-yn-1-yl ester 1i (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1i disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate three times, and the organic phases were combined and washed with saturated brine three times, and washed with anhydrous Na 2 SO4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3ia.

[0072] The product testing data are as follows: White amorphous solid, yield 76%.

[0073] 1 H NMR (400 MHz, CDCl 3 ) δ 7.81 (d, J = 8.8 Hz, 2H), 7.67 (ddd, J = 18.6,11.3, 7.9 Hz, 6H), 7.51 – 7.28 (m, 14H), 6.84 (d, J = 8.8 Hz, 2H), 4.17 – 3.99(m, 2H), 3.81 (s, 3H), 3.16 – 3.00 (m, 1H), 2.65 – 2.55 (m, 2H), 2.35 – 2.19(m, 1H), 2.18-2.04 (m, 1H). 13 C NMR (100 MHz, CDCl 3 ) δ 165.44 (s), 163.03 (s), 132.87 (d, J = 100.9Hz), 132.46 (s), 28.11 (d, J = 68.8 Hz),131.82 (t, J = 2.5 Hz), 131.80 (dd, J =23.1, 2.6 Hz), 131.46 (s), 131.07 (d, J = 97.5 Hz), 130.83 (dd, J = 16.4, 8.8Hz), 130.60 (dd, J = 30.0, 9.1 Hz), 130.49 (d, J = 22.5 Hz), 128.80 (s), 128.62(dt, J = 5.5, 2.4 Hz), 122.55 (s), 113.30 (s), 61.79 (d, J= 6.0 Hz), 55.27 (s), 40.80 (s), 28.65 (dd, J = 69.4, 3.8 Hz), 28.11 (d, J = 68.8 Hz), 27.90 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 36.43 (d, J = 40.6 Hz), 31.58 – 29.31 (m).

[0074] Example 10 1,2-Bisphosphonylethane compounds were prepared using N,N-dimethylpent-4-ynamide and diphenylphosphine oxide as raw materials.

[0075]

[0076] Under argon atmosphere, N,N-dimethylpent-4-ynamide 1j (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1j disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3ja.

[0077] The product testing data are as follows: White solid, yield 83%.

[0078] 1H NMR (400 MHz, CDCl 3 ) δ 7.81 (dd, J = 10.2, 7.4 Hz, 2H), 7.71 – 7.61(m, 4H), 7.50 – 7.30 (m, 14H), 3.13 – 2.96 (m, 1H), 2.81 (d, J = 9.8 Hz, 6H), 2.71 – 2.59 (m, 1H), 2.55 – 2.42 (m, 3H), 2.27 – 2.10 (m, 1H), 1.94-1.79 (m, 1H). 13 C NMR (100 MHz, CDCl 3 ) δ 171.87 (s), 133.28 (d, J = 99.2 Hz), 132.23(d, J = 33.1 Hz), 131.79 (d, J = 2.8 Hz), 131.74 – 131.59 (m), 131.25 (d, J = 30.8Hz), 131.02 (dd, J = 14.7, 8.8 Hz), 130.63 (dd, J = 27.5, 9.2 Hz), 128.65 (t, J =11.6 Hz), 128.62 (d, J = 13.0 Hz), 40.90 (s), 36.93 (s), 35.20 (s), 30.65 (dd, J = 73.7, 8.8 Hz), 27.61 (d, J = 68.4 Hz), 24.20 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 37.59 (d, J = 44.6 Hz), 31.48 – 29.78 (m).

[0079] Embodiment 11 1,2-Bisphosphonylethane compounds were prepared using 2-propylpentanoic acid pent-4-yn-1-yl ester and diphenylphosphine oxide as raw materials.

[0080]

[0081] Under argon atmosphere, 2-propylpentanoic acid pent-4-yn-1-yl ester 1k (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1k disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate 3 times, the organic phases were combined, and the organic phases were washed 3 times with saturated brine and washed with anhydrous Na 2 SO 4The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE: EA = 1:1-1:3) to obtain the target product 3ka.

[0082] The product testing data are as follows: White amorphous solid, yield 76%.

[0083] 1 H NMR (400 MHz, CDCl 3 ) δ 7.81 – 7.71 (m, 6H), 7.55 – 7.35 (m, 14H), 3.65 – 3.49 (m, 2H), 3.11 – 2.96 (m, 1H), 2.71 – 2.50 (m, 2H), 2.21 – 2.08(m, 1H), 1.92 – 1.71 (m, 2H), 1.65 – 1.49 (m, 1H), 1.48 – 1.35 (m, 3H), 1.28(dt, J = 12.1, 7.2 Hz, 2H), 1.22 – 1.10 (m, 4H), 0.92 – 0.78 (m, 6H). 13 C NMR (100 MHz, CDCl 3 ) δ 176.19 (s), 133.08 (d, J = 99.2 Hz), 132.66(d, J = 100.8 Hz), 131.91 – 131.58 (m), 131.49 (d, J = 95.4 Hz), 131.11 (d, J =10.1 Hz), 130.82 (dd, J = 11.0, 8.6 Hz), 130.47 (d, J = 9.3 Hz), 128.65 (dd, J =22.9, 11.4 Hz), 128.60 (dd, J = 12.3, 1.3 Hz), 63.60 (s), 44.94 (s), 34.30 (s), 30.52 (d, J = 3.9 Hz), 26.85 (d, J = 68.9 Hz), 25.71 (d, J= 4.5 Hz), 24.59 (s), 20.40 (s), 13.90 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 37.70 – 35.97 (m), 30.01 (ddd, J = 48.2,24.1, 12.0 Hz).

[0084] Example 12 1,2-Bisphosphonylethane compounds were prepared from hept-1-yne and diphenylphosphine oxide.

[0085]

[0086] Under argon atmosphere, hept-1-yne 1l (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1l disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 31a.

[0087] The product testing data are as follows: Colorless colloid, yield 73%.

[0088] 1 H NMR (400 MHz, CDCl 3 ) δ 7.83 – 7.70 (m, 6H), 7.54 – 7.33 (m, 14H), 3.08 – 2.92 (m, 1H), 2.72 – 2.60 (m, 1H), 2.60 – 2.47 (m, 1H), 1.83 – 1.63(m, 1H), 1.46 (dt, J = 14.2, 4.3 Hz, 1H), 1.34 – 1.19 (m, 1H), 1.01 – 0.85 (m,3H), 0.81 – 0.68 (m, 2H), 0.64 (t, J = 7.3 Hz, 3H). 13C NMR (100 MHz, CDCl 3 ) δ 133.24 (d, J = 99.7 Hz), 133.16 (d, J = 100.7Hz), 131.97 (d, J = 96.5 Hz), 131.82 (d, J = 96.3 Hz), 131.77 (d, J = 2.8 Hz),131.67 (d, J = 2.8 Hz), 131.62 (d, J = 2.7 Hz), 130.96 (dd, J = 16.4, 8.7 Hz),130.61 (dd, J = 14.5, 9.4 Hz), 128.79 (d, J = 11.2 Hz), 128.66 (d, J = 2.2 Hz),128.55 (d, J = 2.1 Hz), 128.49 (d, J = 9.5 Hz), 31.66 (s), 31.23 (dd, J = 69.4, 3.8Hz), 28.15 (s), 27.33 (d, J = 69.1 Hz), 26.65 (d, J = 4.3 Hz), 21.96 (s), 13.82 (s). 31 P NMR (162 MHz, CDCl 3 ) δ 37.05 (s), 30.14 (dd, J = 48.3, 11.1 Hz).

[0089] Embodiment 13 1,2-Bisphosphonylethane compounds were prepared using (prop-2-ynyloxy)benzene and diphenylphosphine oxide as raw materials.

[0090]

[0091] Under argon atmosphere, (prop-2-ynyloxy)benzene 1m (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1m disappeared. After the reaction was completed, the reaction system was extracted with ethyl acetate 3 times, the organic phases were combined, and the organic phases were washed 3 times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE: EA = 1:1-1:3) to obtain the target product 3ma.

[0092] The product testing data are as follows: White amorphous solid, yield 80%.

[0093] 1 H NMR (400 MHz, CDCl 3 ) δ 7.79-7.65 (m, 6H), 7.58 (dd, J = 11.1, 7.8 Hz,2H), 7.53 – 7.29 (m, 12H), 7.07 (t, J = 7.8 Hz, 2H), 6.82 (t, J = 7.3 Hz, 1H),6.36 (d, J = 8.1 Hz, 2H), 4.37 (ddd, J = 17.4, 9.9, 3.7 Hz, 1H), 4.18 – 4.04 (m,1H), 3.44 (dd, J = 8.5, 5.0 Hz, 1H), 2.75 – 2.63 (m, 2H). 13 C NMR (100 MHz, CDCl 3 ) δ 157.37 (s), 132.76 (d, J = 99.1 Hz), 132.40(d, J = 78.0 Hz), 131.87 (d, J = 2.7 Hz), 131.82 (d, J = 3.0 Hz), 131.69 (d, J = 3.2Hz), 131.57 (d, J= 20.3 Hz), 131.25 (t, J = 8.7 Hz), 130.74 (d, J = 9.4 Hz),130.47 (d, J = 10.7 Hz), 130.43 (d, J = 9.9 Hz), 128.96 (s), 128.76 (d, J = 9.3Hz), 128.67 (d, J = 1.1 Hz), 128.58 (d, J = 4.3 Hz), 128.38 (d, J = 11.9 Hz),128.57 (d, J = 11.9 Hz), 120.69 (s), 114.11 (s), 64.66 (d, J = 3.6 Hz), 33.17(dd, J = 68.5, 4.0 Hz), 24.84 (d, J = 68.4 Hz). 31 P NMR (162 MHz, CDCl 3 ) δ 34.84 (s), 31.62 – 30.56 (m).

[0094] Embodiment 14 1,2-Bisphosphonylethane compounds were prepared from hex-5-yn-1-ol and diphenylphosphine oxide.

[0095]

[0096] Under argon atmosphere, hex-5-yn-1-ol 1n (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), and photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1n disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined, and the organic phases were washed three times with saturated brine and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure, and finally filtered through a silica gel column (PE: EA = 1:1-1:3) to obtain the target product 3na.

[0097] The product testing data are as follows: Colorless colloid, yield 54%.

[0098] 1 H NMR (400 MHz, CDCl 3 ) δ 7.76 – 7.61 (m, 6H), 7.58 – 7.38 (m, 14H), 3.47 (t, J = 5.6 Hz, 2H), 2.78 – 2.62 (m, 2H), 2.53 – 2.37 (m, 1H), 1.98 – 1.78(m, 1H), 1.73 – 1.49 (m, 2H), 1.42 (s, 1H), 1.34 – 1.14 (m, 3H). 13 C NMR (100 MHz, CDCl 3 ) δ 133.17 (d, J = 101.2 Hz), 132.02 (d, J = 2.9Hz), 131.91 (d, J = 2.8 Hz), 131.31 (d, J = 94.8 Hz), 130.95 (d, J = 9.3 Hz),130.94 (d, J = 9.1 Hz), 130.47 (d, J = 9.5 Hz), 128.84 (d, J = 11.7 Hz), 128.70(dd, J = 10.6, 4.0 Hz), 60.40 (s), 31.97 (dd, J = 68.9, 3.9 Hz), 31.52 (s), 27.28(d, J = 68.9 Hz), 26.56 (s), 22.78 (d, J = 4.9 Hz). 31 P NMR (162 MHz, CDCl 3 ) δ 37.06 (s), 31.93 (d, J = 51.8 Hz).

[0099] Embodiment 15 1,2-Bisphosphonylethane compounds were prepared using prop-2-yn-1-yl benzoate and diphenylphosphine oxide as raw materials.

[0100]

[0101] Under argon atmosphere, benzoic acid prop-2-yn-1-yl ester 1o (0.2 mmol), diphenylphosphine oxide 2a (0.8 mmol), photocatalyst 4CzIPN (2%) were added to a dry 10 mL Schlenk reaction tube, and 1 mL of dimethyl sulfoxide was added. The reaction was stirred for 36 h at room temperature under 12 W 460 nm LED blue light until the raw material 1o disappeared. After the reaction, the reaction system was extracted with ethyl acetate three times, the organic phases were combined and washed with saturated brine three times, and washed with anhydrous Na 2 SO 4 The organic phase was dried and then concentrated under reduced pressure and finally filtered through a silica gel column (PE:EA = 1:1-1:3) to obtain the target product 3oa.

[0102] The product testing data are as follows: Colorless colloid, yield 71%.

[0103] 1 H NMR (400 MHz, CDCl 3 ) δ 7.87-7.65 (m, 8H), 7.58 – 7.26 (m, 17H), 4.53 (ddd, J = 22.4, 11.9, 5.3 Hz, 1H), 4.45 – 4.35 (m, 1H), 3.50 (d, J = 5.6 Hz,1H), 2.93 – 2.81 (m, 1H), 2.66 (dd, J = 27.4, 13.2 Hz, 1H). 13 C NMR (100 MHz, CDCl 3 ) δ 165.41 (s), 132.49 (d, J = 101.3 Hz), 132.33(d, J = 103.2 Hz), 132.25 (d, J = 93.0 Hz), 131.93 (t, J = 2.0 Hz), 131.80 (d, J =5.1 Hz), 131.74 (d, J = 53.9 Hz), 131.65 (d, J= 33.4 Hz), 130.77 (d, J = 98.2 Hz),130.85 (dd, J = 20.5, 8.9 Hz), 130.45 (dd, J = 13.8, 6.1 Hz), 129.60 (s), 129.32(s), 128.87 (d, J = 11.4 Hz), 128.63 (d, J = 13.1 Hz), 128.59 (d, J = 11.8 Hz),128.02 (s), 62.00 (d, J = 4.3 Hz), 32.12 (dd, J = 68.4, 4.0 Hz), 24.79 (d, J = 68.2Hz). 31 P NMR (162 MHz, CDCl 3 ) δ 33.89 (dd, J = 45.7, 23.5 Hz), 30.48 – 29.55(m).

[0104] Example 16 According to the method described in Example 1, the photocatalyst and solvent were screened by the controlled variable method to observe their effects on the yield.

[0105]

[0106] The comparison of the conditions and product yields is shown in Table 1.

[0107] Table 1 Reaction conditions screening Serial number Solvents Photocatalyst Yield (%) 1 MeCN PC1 51% 2 MeCN PC2 13% 3 MeCN PC3 trace 4 MeCN PC4 nd 5 MeCN PC5 27% 6 MeCN PC6 n.r. 7 DMSO PC1 76% 8 DMF PC1 70% 9 THF PC1 31% 10 CyMe:DCM=1:1 PC1 18% 11 NMP PC1 67% 12 Toluene PC1 21% 13 DCE PC1 trace 14 i-PrOH PC1 n.r. <![CDATA[15 a ]]> DMSO PC1 n.r. Note: PC1 =4CzIPN, PC2 =4DPAIPN, PC3 =[Ir(dtbbpy)(ppy) 2 ]PF 6 , PC4 = Ru(bpy) 3 (PF6) 2 ,PC5=Ir(ppy) 3 ,PC6=[Mes-Acr-Ph] + (Cl) - The yield is the NMR phosphine spectrum yield, and triphenylphosphine is used as the internal standard. a No light, other groups are illuminated with blue light.

[0108] From the data results in Table 1, it can be seen that the separation yield under the reaction conditions of the present invention is as high as 76%. A series of control experiments show that light and photocatalyst play an indispensable role in the reaction, and the target product cannot be obtained without any of the conditions. Replacing 4CzIPN with other photocatalysts significantly reduces the yield or does not react at all; replacing the solvent with DCE significantly reduces the yield, and mainly obtains monophosphinated Z-configuration alkenyl phosphine byproducts.

[0109] In summary, the present invention provides a method for preparing 1,2-bisphosphonylethane compounds by neutral photocatalytic diphosphination of alkynes. The method uses diphenylphosphine oxide as a phosphine source under neutral photocatalytic conditions to achieve efficient conversion of alkyne diphosphination to prepare 1,2-bisphosphonylethane derivatives, and is a reaction of two free radical additions of diphenylphosphine oxide to alkynes; the reaction system is simple and clean, without the use of additional acids, bases and other additives, and can be carried out efficiently under mild room temperature and atmospheric pressure conditions; it has high yield and good chemical selectivity, and the reaction substrate range of the present invention is wide, and various functional groups such as methyl, methoxy, phenyl, and halogen are compatible with the reaction; the reaction conditions are mild, and starting from simple and readily available substrate raw materials, the use of complex substrates is avoided, and 1,2-bisphosphonylethane compounds with potential application value can be directly synthesized from commercial alkynes with good to excellent yields. The obtained products can be further derivatized into various diphosphine ligands, showing good application prospects in the fields of catalytic chemistry and materials science.

Claims

1. A catalytic method for preparing 1,2-bisphosphonylethane compounds by neutral photocatalysis, characterized in that: The steps include: ； Wherein, R is a full carbon alkyl group or an alkyl group containing one or more of an aromatic ring, a heteroaromatic ring, a carboxylic acid, an ester group, an amide, an ether and a primary alcohol; (1) Under argon environment, add alkyne compounds, diphenylphosphine oxide and photocatalyst into a Schlenk reaction tube, and add solvent; (2) stirring the reaction mixture at room temperature under visible light until the alkyne compound added in step (1) is completely reacted; (3) After the reaction is completed, the aqueous phase is extracted, the organic phases are combined, washed, and dried, and the organic phase is concentrated under reduced pressure and filtered through a silica gel column to obtain the target product.

2. The catalytic method according to claim 1, characterized in that The solvent in step (1) is any one of dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone, acetonitrile, tetrahydrofuran, toluene, 1,2-dichloroethane and isopropanol.

3. The catalytic method according to claim 2, characterized in that: The solvent in step (1) is any one of acetonitrile, tetrahydrofuran, dimethyl sulfoxide, N,N-dimethylformamide, N-methylpyrrolidone and toluene.

4. The catalytic method according to claim 1, characterized in that The photocatalyst in step (1) is 4CzIPN, 4DPAIPN, [Ir(dtbbpy)(ppy)2]PF6, Ru(bpy)3(PF6)2, Ir(ppy)3 and [Mes-Acr-Ph] + (Cl) - Any of .

5. The catalytic method according to claim 1, characterized in that: The photocatalyst described in step (1) is any one of 4CzIPN, 4DPAIPN and Ir(ppy)3.

6. The catalytic method according to claim 1, characterized in that: The visible light described in step (2) is 430-460 nm blue light, and the light source power is 1-100 W.

7. The catalytic method according to claim 1, characterized in that: The stirring time in step (2) is 24-36 hours.

8. The catalytic method according to claim 1, characterized in that: The extraction in step (3) uses ethyl acetate, and the washing uses saturated brine.

9. The catalytic method according to claim 1, characterized in that: The drying in step (3) uses anhydrous Na2SO4.

10. The catalytic method according to claim 1, characterized in that: In the silica gel column described in step (3), PE:EA =1:1-1:3.

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