Phosphinimine compounds containing n=p bonds and two- and three-component synthesis methods thereof

Abstract

This invention belongs to the field of chemical synthesis technology, specifically relating to a novel method for synthesizing phosphonium imide compounds containing N=P double bonds, including two-component and three-component reaction methods. The two-component synthesis method involves adding N-aminopyridine tetrafluoroborate, a trisubstituted phosphorus compound, a catalyst, and a solvent to a reactor, followed by the addition of a base as a promoter. An inert gas is introduced, and the mixture is stirred for 2 hours at room temperature under blue light irradiation. After the reaction, the mixture is filtered, and the solvent is removed under reduced pressure to obtain a crude product. This crude product is then purified by column chromatography to obtain a phosphonium imide compound. The three-component synthesis method involves adding diphenylphosphine chloride, an alcohol compound, and a solvent to a reactor, followed by the addition of a base as a promoter. The mixture is stirred at 25°C for 6 hours, and after filtration, a trivalent phosphine oxide compound is obtained. Next, the trivalent phosphine oxide compound, N-aminopyridine tetrafluoroborate, a catalyst, and a solvent are added to the reactor, followed by the addition of a base as a promoter. An inert gas is introduced, and the mixture is stirred for 12 hours at 25°C under blue light irradiation. After the reaction, the mixture is separated and purified to obtain a novel phosphonium imide compound. This method is safe and simple to operate, has low raw material costs, and is conducive to industrial production.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis technology, specifically relating to a novel method for synthesizing phosphonium imide compounds containing N=P double bonds, including two-component and three-component reaction methods. Background Technology

[0002] Phosphine imides and their derivatives possess highly polarized N=P double bonds, and due to their unique physicochemical properties, they have important applications in synthetic chemistry and materials science. Many transition metals (such as gold, palladium, and platinum) can react with phosphine imide compounds to form metal complexes with pharmaceutical and catalytic activity.

[0003] Furthermore, phosphonium imides have wide applications in organic synthesis, biomedicine, and polymer science. Particularly in organocatalysis, phosphonium imides play a crucial role as a class of bifunctional, strongly basic ligand catalysts. Traditionally, the synthesis of phosphonium imides has relied primarily on the Staudinger and Kirsanov reactions. The former involves the coupling reaction of an acyl azide with triphenylphosphine, but this reaction uses azide compounds, posing safety risks. The latter requires bromine water to convert triphenylphosphine into triphenylphosphine bromide, which is not only highly toxic but also involves a complex synthetic process. Summary of the Invention

[0004] In order to overcome the shortcomings and deficiencies of the prior art, the primary objective of this invention is to provide a new two-component and three-component method for synthesizing N=P bonded phosphonium imide compounds using N-aminopyridine salt compounds as starting materials.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A novel method for synthesizing two-component phosphonium imide compounds containing N=P bonds, comprising the following steps:

[0007] (1) In a reactor, N-aminopyridine tetrafluoroborate (compound 1), trisubstituted phosphorus compound (compound 2), catalyst and solvent were added, and then alkali was added as a promoter. An inert gas was introduced and the mixture was stirred for 2 hours at room temperature and under blue light irradiation. After the reaction was completed, the mixture was filtered and the solvent was removed by vacuum distillation to obtain a crude product. The crude product was purified by column chromatography to obtain a phosphonium imide compound.

[0008] The compound 1 refers to N-aminopyridine tetrafluoroborate having the structure of formula (1); the compound 2 refers to a trisubstituted phosphorus compound having the structure of formula (2), such as triphenylphosphine, tris(o-methylphenyl)phosphine, tris(3-fluorophenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(2-thienyl)phosphine, and tributyl phosphite.

[0009]

[0010] Among them, R 1 Selected from alkyl and aryl groups; R 2 R is an alkyl substituent on the pyridine ring. 3 R 4 R 5 Each is independently selected from aryl, alkyl, or alkoxy groups.

[0011] The reaction equations involved in the above synthesis method are as follows:

[0012]

[0013] The reactor is preferably a Schlenk tube; the inert gas is nitrogen or argon.

[0014] The preferred molar ratio of compound 1 to compound 2 is 1:1.2.

[0015] The catalyst is one of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate, tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate), tris(2,2'-bipyridine)ruthenium(II) chloride, tris(1,10-phenanthroline)ruthenium(II) chloride, phenyl-1,10-phenanthroline)copper(I) chloride, 9-trimethyl-10-methylacridinium perchlorate, 10-phenylphenthiazine, eosin Y, tris(2-phenylpyridine)iridium, 2,4,5,6-tetra(9-carbazolyl)-isophthalonitrile, and 9-thioxanone.

[0016] The solvent is one or a mixture of two or more of the following: 1,2-dichloroethane, dichloromethane, chloroform, chlorobenzene, trifluorotoluene, N,N-dimethylformamide, dimethyl sulfoxide, toluene, xylene, tetrahydrofuran, diethyl ether, 1,4-dioxane, and ethyl acetate.

[0017] The alkali is one of potassium carbonate, sodium carbonate, cesium carbonate, sodium bicarbonate, sodium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, potassium phosphate, potassium hydroxide, potassium tert-butoxide, potassium acetate, ethylenetriamine, and diisopropylethylamine; the molar ratio of the alkali added to compound 1 is preferably 1:1.

[0018] The eluent used for column chromatography purification is a mixture of petroleum ether and ethyl acetate.

[0019] A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds, comprising the following steps:

[0020] (1) Compound 4, compound 5 and solvent were added to the reactor, and then alkali was added as a promoter. The mixture was stirred at 25°C for 6 hours and filtered to obtain a trivalent phosphine oxide 6.

[0021] (2) Next, trivalent phosphine oxide 6, compound 1, catalyst and solvent were added to the reactor, and then alkali was added as a promoter. Inert gas was introduced and the mixture was stirred for 12 hours at 25°C under blue light irradiation. After the reaction was completed, the mixture was filtered and the solvent was removed by vacuum distillation to obtain crude product. A novel phosphine imide compound was obtained by column chromatography purification.

[0022] Compound 4 refers to a compound having the structure of formula (4): diphenylphosphine chloride; Compound 5 refers to an alcohol compound having the structure of formula (5), such as citronellol, tert-butyl 6-hydroxy-2-azaspiro[3.3]heptane-2-carboxylate, etc.; Compound 1 refers to N-aminopyridine tetrafluoroborate having the structure of formula (1).

[0023]

[0024] The reaction equations involved in the above synthesis method are as follows:

[0025]

[0026] The reactor is preferably made of Schlenk tubing.

[0027] The inert gas is either nitrogen or argon.

[0028] The preferred molar ratio of compound 4, compound 5 and compound 1 is 3:3:1.

[0029] The catalyst is one of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate, tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate), tris(2,2'-bipyridine)ruthenium(II) chloride, tris(1,10-phenanthroline)ruthenium(II) chloride, phenyl-1,10-phenanthroline)copper(I) chloride, 9-trimethyl-10-methylacridinium perchlorate, 10-phenylphenthiazine, eosin Y, tris(2-phenylpyridine)iridium, 2,4,5,6-tetra(9-carbazolyl)-isophthalonitrile, and 9-thioxanone.

[0030] The solvent is one or a mixture of two or more of the following: 1,2-dichloroethane, dichloromethane, chloroform, chlorobenzene, trifluorotoluene, N,N-dimethylformamide, dimethyl sulfoxide, toluene, xylene, tetrahydrofuran, diethyl ether, 1,4-dioxane, and ethyl acetate.

[0031] The alkali is one of potassium carbonate, sodium carbonate, cesium carbonate, sodium bicarbonate, sodium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, potassium phosphate, potassium hydroxide, potassium tert-butoxide, potassium acetate, ethylenetriamine, and diisopropylethylamine; the molar ratio of the alkali added to compound 1 is preferably 1:1. The eluent used for column chromatography purification is a mixture of petroleum ether and ethyl acetate.

[0032] The preparation method and the obtained products of the present invention have the following advantages and beneficial effects: The present invention uses N-aminopyridine salt as raw material and rapidly synthesizes novel and diverse phosphonium imide compounds through two-component and three-component reaction processes. It has the advantages of simple synthesis steps, safe operation of synthesis method, non-toxic raw materials, low price and good adaptability to functional groups. Attached Figure Description

[0033] Figure 1 , Figure 2 and Figure 3 The images shown are the proton, carbon, and phosphine spectra of the product obtained in Example 1.

[0034] Figure 4 , Figure 5 , Figure 6 and Figure 7 The following are the proton, carbon, fluorine, and phosphine spectra of the product obtained in Example 2;

[0035] Figure 8 , Figure 9 and Figure 10 The images shown are the proton, carbon, and phosphine spectra of the product obtained in Example 3.

[0036] Figure 11 , Figure 12 and Figure 13 The images shown are the proton, carbon, and phosphine spectra of the product obtained in Example 4.

[0037] Figure 14 , Figure 15 and Figure 16 The images shown are the proton, carbon, and phosphine spectra of the product obtained in Example 5.

[0038] Figure 17 , Figure 18 and Figure 19 The images shown are the proton, carbon, and phosphine spectra of the product obtained in Example 6.

[0039] Figure 20 , Figure 21 and Figure 22 The images shown are the proton, carbon, and phosphine spectra of the product obtained in Example 7.

[0040] Figure 23 , Figure 24 and Figure 25 The images show the proton, carbon, and phosphine spectra of the intermediate product obtained in Example 8, respectively.

[0041] Figure 26 , Figure 27 and Figure 28 The images shown are the proton spectrum, carbon spectrum, and phosphine spectrum of the target product obtained in Example 9, respectively. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto. Example 1 Under nitrogen protection, 0.1 mmol of N-aminophenylazomonium tetrafluoroborate, 0.12 mmol of triphenylphosphine, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and irradiated with blue light for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 5:1, and the yield was 87%.

[0043] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 1 , Figure 2 and Figure 3 As shown, the structural characterization data are as follows:

[0044] 1 H NMR (500 MHz, Chloroform-d) δ 8.34 (d, J = 7.4 Hz, 2H), 7.89 –7.79 (m, 6H), 7.58 – 7.39 (m, 12H).

[0045] 13C NMR (126 MHz, Chloroform-d) δ 176.39 (d, J = 8.2 Hz), 138.57 (d, J= 20.5 Hz), 133.19 (d, J = 9.9 Hz), 132.26 (d, J = 3.0 Hz), 130.73, 129.54(d, J = 2.4 Hz), 128.70 (d, J = 12.4 Hz), 127.94, 127.69.

[0046] 31 P NMR (162 MHz, Chloroform-d) δ 20.73.

[0047] Based on the above data, the structure of the product is inferred as follows:

[0048]

[0049] Example 2 Under nitrogen protection, 0.1 mmol of N-amino-p-fluorophenyl azomonium tetrafluoroborate, 0.12 mmol of triphenylphosphine, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and irradiated with blue light for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 3:1, and the yield was 72%.

[0050] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 4 , Figure 5 , Figure 6 and Figure 7 As shown, the structural characterization data are as follows:

[0051] 1 H NMR (500 MHz, Chloroform-d) δ 8.33 (t, J = 8.0 Hz, 2H), 7.82 (dd,J = 12.3, 7.0 Hz, 6H), 7.56 (t, J = 6.6 Hz, 3H), 7.48 (td, J = 7.7, 3.0 Hz, 6H), 7.04 (t, J = 8.7 Hz, 2H).

[0052] 13C NMR (126 MHz, Chloroform-d) δ 175.29 (d, J = 7.9 Hz), 164.72 (d, J = 249.3 Hz), 133.15 (d, J = 9.9 Hz), 132.32 (d, J = 2.9 Hz), 131.79 (dd, J =8.8, 2.4 Hz), 129.06 – 128.40 (m), 127.84, 114.41 (d, J = 21.3 Hz).

[0053] 19 F NMR (471 MHz, Chloroform-d) δ -110.68.

[0054] 31 P NMR (162 MHz, Chloroform-d) δ 20.86.

[0055] HRMS (ESI): Calculated for C 25 H 20 FNOP [M+H] + : 400.1261; found: 400.1261.

[0056] Based on the above data, the structure of the product is inferred as follows:

[0057]

[0058] Example 3 Under nitrogen protection, 0.1 mmol of N-amino-p-methylphenyl azomonium tetrafluoroborate, 0.12 mmol of triphenylphosphine, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and under blue light irradiation for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 5:1, and the yield was 85%.

[0059] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 8 , Figure 9 and Figure 10 As shown, the structural characterization data are as follows:

[0060] 1H NMR (500 MHz, Chloroform-d) δ 8.23 ​​(d, J = 8.2 Hz, 1H), 7.83 (dd,J = 12.4, 7.6 Hz, 7H), 7.57 – 7.51 (m, 3H), 7.46 (td, J = 7.6, 3.0 Hz, 7H), 7.19 (d, J = 7.7 Hz, 3H), 2.38 (s, 3H).

[0061] 13 C NMR (126 MHz, Chloroform-d) δ 176.45 (d, J = 8.1 Hz), 140.85,135.95 (d, J = 20.3 Hz), 133.20 (d, J = 9.8 Hz), 132.19 (d, J = 2.8 Hz), 129.61 (d, J = 2.5 Hz), 128.82 (d, J = 24.9 Hz), 128.51 (d, J = 27.3 Hz), 128.13, 21.54.

[0062] 31 P NMR (162 MHz, Chloroform-d) δ 20.48.

[0063] HRMS (ESI): Calculated for C 26 H 23 NOP [M+H] + : 396.1512; found: 396.1513.

[0064] Based on the above data, the structure of the product is inferred as follows:

[0065]

[0066] Example 4 Under nitrogen protection, 0.1 mmol of N-amino-p-methoxyphenyl azomonium tetrafluoroborate, 0.12 mmol of triphenylphosphine, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and irradiated with blue light for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 3:1, and the yield was 77%.

[0067] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 11 , Figure 12 and Figure 13 As shown, the structural characterization data are as follows:

[0068] 1 H NMR (500 MHz, Chloroform-d) δ 8.30 (d, J = 8.8 Hz, 1H), 7.83 (dd,J = 12.3, 6.9 Hz, 2H), 7.53 (td, J = 7.3, 1.6 Hz, 2H), 7.45 (td, J = 7.7, 3.2Hz, 4H), 6.89 (d, J = 8.8 Hz, 1H), 3.82 (s, 2H).

[0069] 13 C NMR (126 MHz, Chloroform-d) δ 176.07 (d, J = 8.0 Hz), 161.83,133.18 (d, J = 9.8 Hz), 132.19 (d, J = 2.9 Hz), 131.39 (d, J = 2.7 Hz), 128.96, 128.67 (d, J = 12.3 Hz), 128.17, 112.84, 55.33.

[0070] 31 P NMR (162 MHz, Chloroform-d) δ 20.30.

[0071]

[0072] Example 5

[0073] Under nitrogen protection, 0.1 mmol of N-aminophenylazomonium tetrafluoroborate, 0.12 mmol of tris(o-methylphenyl)phosphine, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and irradiated with blue light for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 5:1, and the yield was 65%.

[0074] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 14 , Figure 15 and Figure 16 As shown, the structural characterization data are as follows:

[0075] 1 H NMR (500 MHz, Chloroform-d) δ 8.23 ​​(d, J = 7.1 Hz, 1H), 7.58 (dd,J = 15.0, 7.5 Hz, 1H), 7.46 (t, J = 7.6 Hz, 1H), 7.39 (d, J = 7.2 Hz, 0H), 7.34 (t, J = 7.4 Hz, 1H), 7.31 – 7.23 (m, 3H), 2.28 (s, 5H).

[0076] 13 C NMR (126 MHz, Chloroform-d) δ 174.95 (d, J = 9.2 Hz), 143.02 (d, J= 7.9 Hz), 139.19 (d, J = 21.2 Hz), 134.34 (d, J = 12.7 Hz), 132.38 – 132.09(m), 130.39, 129.50 (d, J = 2.4 Hz), 127.60, 126.44, 126.08 (d, J = 12.9 Hz), 125.68, 22.28 (d, J = 3.3 Hz).

[0077] 31 P NMR (162 MHz, Chloroform-d) δ 23.64.

[0078] HRMS (ESI): Calculated for C 28 H 27 NOP [M+H] + : 424.1825; found: 424.1826.

[0079] Based on the above data, the structure of the target product is inferred as follows:

[0080]

[0081] Example 6

[0082] Under nitrogen protection, 0.1 mmol of N-aminophenylazomonium tetrafluoroborate, 0.12 mmol of tris(2-thienyl)phosphine, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and under blue light irradiation for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 3:1, and the yield was 74%.

[0083] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 17 , Figure 18 and Figure 19 As shown, the structural characterization data are as follows:

[0084] 1 H NMR (500 MHz, Chloroform-d) δ 8.30 (d, J = 6.9 Hz, 1H), 7.78 (t, J= 4.6 Hz, 2H), 7.64 (dd, J = 8.2, 3.7 Hz, 2H), 7.43 (t, J = 7.2 Hz, 1H), 7.38(t, J = 7.3 Hz, 2H), 7.18 (dd, J = 6.0, 4.7 Hz, 1H).

[0085] 13 C NMR (126 MHz, Chloroform-d) δ 177.00 (d, J = 8.4 Hz), 138.20 (d, J= 11.7 Hz), 137.76 (d, J = 20.5 Hz), 135.29 (d, J = 5.1 Hz), 131.03, 130.56,129.59 (d, J = 2.6 Hz), 128.41 (d, J = 15.6 Hz), 127.74.

[0086] 31 P NMR (162 MHz, Chloroform-d) δ 1.38.

[0087] HRMS (ESI): Calculated for C 19 H 15 NOPS3 [M+H] + : 400.0048; found: 400.0042.

[0088]

[0089] Example 7

[0090] Under nitrogen protection, 0.1 mmol of N-aminophenylazomonium tetrafluoroborate, 0.12 mmol of tributyl phosphite, 0.1 mmol of potassium carbonate, 0.001 mmol of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate and 1 mL of 1,2-dichloroethane were added to a reaction flask. The mixture was stirred at 25 °C and under blue light irradiation for 2 hours. After filtration, the solvent was removed by vacuum distillation to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 3:1, and the yield was 65%.

[0091] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 20 , Figure 21 and Figure 22 As shown, the structural characterization data are as follows:

[0092] 1 H NMR (500 MHz, Chloroform-d) δ 8.18 (d, J = 6.8 Hz, 1H), 7.37 (s,1H), 4.22 (q, J = 6.7 Hz, 4H), 1.76 – 1.66 (m, 2H), 1.49 – 1.38 (m, 2H), 0.94(t, J = 7.5 Hz, 6H).

[0093] 13 C NMR (126 MHz, Chloroform-d) δ 174.41 (d, J = 2.7 Hz), 137.64 (d, J= 27.0 Hz), 131.04, 129.56 (d, J = 2.6 Hz), 127.70, 68.62 (d, J = 6.4 Hz),32.23 (d, J = 7.1 Hz), 18.69, 13.58.

[0094] 31 P NMR (162 MHz, Chloroform-d) δ 14.76.

[0095] HRMS (ESI): Calculated for C 19 H33NO4P [M+H] +: 370.2142; found: 370.2149.

[0096]

[0097] Example 8

[0098] 0.3 mmol diphenylphosphine chloride, 0.3 mmol β-citronellol, and 1 mL acetonitrile were added to a Schlenk tube and stirred at 25 °C for 6 hours. After filtration, trivalent phosphine oxide was obtained. Next, under nitrogen protection, 0.1 mmol N-aminophenylazomonium tetrafluoroborate, trivalent phosphine oxide, 0.1 mmol potassium carbonate, 0.001 mmol (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate, and 1 mL 1,2-dichloroethane were added to a reaction flask and stirred at 25 °C under blue light for 12 hours. After filtration, the solvent was removed under reduced pressure to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 4:1, and the yield was 45%.

[0099] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 23 , Figure 24 and Figure 25 As shown, the structural characterization data are as follows:

[0100] 1 H NMR (500 MHz, Chloroform-d) δ 8.32 (d, J = 6.8 Hz, 1H), 7.92 (dd,J = 12.6, 7.6 Hz, 3H), 7.57 – 7.51 (m, 1H), 7.50 – 7.43 (m, 3H), 7.41 (t, J =7.4 Hz, 1H), 5.05 (s, 0H), 4.31 – 4.20 (m, 1H), 2.01 – 1.89 (m, 1H), 1.81(dd, J = 13.2, 5.7 Hz, 0H), 1.61 (d, J = 45.3 Hz, 5H), 1.36 – 1.24 (m, 0H),1.20 – 1.11 (m, 0H), 0.87 (d, J = 6.6 Hz, 2H).

[0101] 13C NMR (126 MHz, Chloroform-d) δ 175.68 (d, J = 7.3 Hz), 138.17 (d, J= 20.7 Hz), 132.42 (d, J = 2.9 Hz), 132.13 (d, J = 10.2 Hz), 131.28, 130.98,129.96, 129.64 (d, J = 2.4 Hz), 128.90, 128.65 (d, J = 13.1 Hz), 127.74,124.60, 65.72 (d, J = 6.5 Hz), 37.38 (d, J = 6.8 Hz), 36.93, 29.11, 25.54 (d,J = (44.1 Hz), 19.35, 17.66.

[0102] 31 P NMR (162 MHz, Chloroform-d) δ 36.02.

[0103] HRMS (ESI): Calculated for C 29 H 35 NO2P [M+H] + : 460.2400; found: 460.2400.

[0104]

[0105] Example 9

[0106] 0.3 mmol diphenylphosphine chloride, 0.3 mmol tert-butyl 6-hydroxy-2-azaspiro[3.3]heptane-2-carboxylate, and 1 mL acetonitrile were added to a Schlenk tube and stirred at 25 °C for 6 hours. After filtration, trivalent phosphine oxide was obtained. Next, under nitrogen protection, 0.1 mmol N-aminophenylazomonium tetrafluoroborate, trivalent phosphine oxide, 0.1 mmol potassium carbonate, 0.001 mmol (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate, and 1 mL 1,2-dichloroethane were added to a reaction flask and stirred at 25 °C under blue light for 12 hours. After filtration, the solvent was removed under reduced pressure to obtain the target product. The column chromatography eluent was a petroleum ether:ethyl acetate mixture with a volume ratio of 3:1, and the yield was 68%.

[0107] The proton, carbon, and phosphine spectra of the obtained product are as follows: Figure 26 , Figure 27 and Figure 28 As shown, the structural characterization data are as follows:

[0108] 1 H NMR (500 MHz, Chloroform-d) δ 8.29 (d, J = 7.3 Hz, 1H), 7.89 (dd,J = 12.6, 7.4 Hz, 2H), 7.55 (t, J = 7.3 Hz, 1H), 7.47 (td, J = 7.8, 3.2 Hz,2H), 7.41 (t, J = 7.4 Hz, 1H), 4.87 (q, J = 7.2 Hz, 0H), 3.86 (s, 1H), 3.81(s, 1H), 2.54 (ddd, J = 10.3, 7.1, 3.1 Hz, 1H), 2.48 – 2.41 (m, 1H), 1.39 (s, 5H).

[0109] 13 C NMR (126 MHz, Chloroform-d) δ 175.86 (d, J = 7.4 Hz), 156.04,138.04 (d, J = 20.4 Hz), 132.59 (d, J = 2.8 Hz), 132.09 (d, J = 10.4 Hz),131.12, 129.67, 129.60 (d, J = 2.6 Hz), 128.71 (d, J = 13.3 Hz), 127.80,79.42, 66.87 (d, J = 7.8 Hz), 42.41 (d, J = 4.6 Hz), 30.48, 28.36.

[0110] 31 P NMR (162 MHz, Chloroform-d) δ 34.63.

[0111] HRMS (ESI): Calculated for C 30 H 34 N₂O₄P [M+H] + : 517.2251; found: 517.2252.

[0112] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A novel method for synthesizing two-component phosphonium imide compounds containing N=P bonds, characterized in that: The synthesis steps include the following: (1) In a reactor, N-aminopyridine tetrafluoroborate (compound 1), trisubstituted phosphorus compound (compound 2), catalyst and solvent were added, and then alkali was added as a promoter. An inert gas was introduced and the mixture was stirred for 2 hours at room temperature and under blue light irradiation. After the reaction was completed, the mixture was filtered and the solvent was removed by vacuum distillation to obtain a crude product. The crude product was purified by column chromatography to obtain a phosphonium imide compound. The compound 1 refers to N-aminopyridine tetrafluoroborate having the structure of formula (1); the compound 2 refers to a trisubstituted phosphorus compound having the structure of formula (2), such as triphenylphosphine, tris(o-methylphenyl)phosphine, tris(3-fluorophenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(2-thienyl)phosphine, and tributyl phosphite. Among them, R 1 Selected from alkyl and aryl groups; R 2 R is an alkyl substituent on the pyridine ring. 3 R 4 R 5 Each is independently selected from aryl, alkyl, or alkoxy groups. The reaction equations involved in the above synthesis method are as follows:

2. The novel method for synthesizing a two-component phosphonium imide compound containing an N=P bond according to claim 1, characterized in that: The reactor is preferably a Schlenk tube; the inert gas is nitrogen or argon.

3. The novel method for synthesizing a two-component phosphonium imide compound containing N=P bonds according to claim 1, characterized in that: The preferred molar ratio of compound 1 to compound 2 is 1:1.

2.

4. The novel method for synthesizing a two-component phosphonium imide compound containing an N=P bond according to claim 1, characterized in that: The catalyst is one of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate, tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate), tris(2,2'-bipyridine)ruthenium(II) chloride, tris(1,10-phenanthroline)ruthenium(II) chloride, phenyl-1,10-phenanthroline)copper(I) chloride, 9-trimethyl-10-methylacridinium perchlorate, 10-phenylphenthiazine, eosin Y, tris(2-phenylpyridine)iridium, 2,4,5,6-tetra(9-carbazolyl)-isophthalonitrile, and 9-thioxanone.

5. A novel method for synthesizing a two-component phosphonium imide compound containing an N=P bond according to claim 1, characterized in that: The solvent is one or a mixture of two or more of the following: 1,2-dichloroethane, dichloromethane, chloroform, chlorobenzene, trifluorotoluene, N,N-dimethylformamide, dimethyl sulfoxide, toluene, xylene, tetrahydrofuran, diethyl ether, 1,4-dioxane, and ethyl acetate.

6. A novel method for synthesizing a two-component phosphonium imide compound containing an N=P bond according to claim 1, characterized in that: The alkali is one of potassium carbonate, sodium carbonate, cesium carbonate, sodium bicarbonate, sodium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, potassium phosphate, potassium hydroxide, potassium tert-butoxide, potassium acetate, ethylenetriamine, and diisopropylethylamine; the molar ratio of the alkali added to compound 1 is preferably 1:

1.

7. A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds, comprising the following steps: (1) Compound 4, compound 5 and solvent were added to the reactor, and then alkali was added as a promoter. The mixture was stirred at 25°C for 6 hours and filtered to obtain a trivalent phosphine oxide compound 6. (2) Next, trivalent phosphine oxide compound 6, compound 1, catalyst and solvent were added to the reactor, and then alkali was added as a promoter. Inert gas was introduced and the mixture was stirred at 25°C and under blue light irradiation for 12 hours. After the reaction was completed, the mixture was filtered, and the solvent was removed by vacuum distillation to obtain a crude product. The crude product was purified by column chromatography to obtain a novel phosphine imide compound. Compound 4 refers to a compound having the structure of formula (4): diphenylphosphine chloride; Compound 5 refers to an alcohol compound having the structure of formula (5), such as citronellol, tert-butyl 6-hydroxy-2-azaspiro[3.3]heptane-2-carboxylate, etc.; Compound 1 refers to N-aminopyridine tetrafluoroborate having the structure of formula (1). The reaction equations involved in the above synthesis method are as follows:

8. A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds according to claim 7, characterized in that: The reactor is preferably a Schlenk tube; the inert gas is nitrogen or argon.

9. A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds according to claim 7, characterized in that: The preferred molar ratio of compound 4, compound 5 and compound 1 is 3:3:

1.

10. A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds according to claim 7, characterized in that: The catalyst is one of (4,4-di-tert-butyl-2,2-bipyridine)bis[3,5-difluoro-2-[5-(trifluoromethyl)-2-pyridyl]phenyl]iridium(III) hexafluorophosphate, tris(2,2'-bipyridine)ruthenium di(hexafluorophosphate), tris(2,2'-bipyridine)ruthenium(II) chloride, tris(1,10-phenanthroline)ruthenium(II) chloride, phenyl-1,10-phenanthroline)copper(I) chloride, 9-trimethyl-10-methylacridinium perchlorate, 10-phenylphenthiazine, eosin Y, tris(2-phenylpyridine)iridium, 2,4,5,6-tetra(9-carbazolyl)-isophthalonitrile, and 9-thioxanone.

11. A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds according to claim 7, characterized in that: The solvent is one or a mixture of two or more of the following: 1,2-dichloroethane, dichloromethane, chloroform, chlorobenzene, trifluorotoluene, N,N-dimethylformamide, dimethyl sulfoxide, toluene, xylene, tetrahydrofuran, diethyl ether, 1,4-dioxane, and ethyl acetate.

12. A novel method for synthesizing a three-component phosphonium imide compound containing N=P bonds according to claim 7, characterized in that: The alkali is one of potassium carbonate, sodium carbonate, cesium carbonate, sodium bicarbonate, sodium phosphate, potassium hydrogen phosphate, potassium dihydrogen phosphate, potassium phosphate, potassium hydroxide, potassium tert-butoxide, potassium acetate, ethylenetriamine, and diisopropylethylamine; the molar ratio of the alkali added to compound 1 is preferably 1:

1. The eluent used for column chromatography purification is a mixture of petroleum ether and ethyl acetate.

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