A method for the preparation of phosphorus ylide precursor compounds by functionalization of C-H

Abstract

This invention discloses a method for preparing phosphorus ylide precursor compounds by C-H functionalization. The method uses vinylphosphine cations and aldehydes or cycloalkanes as raw materials, with TBADT as a photocatalyst. Under light irradiation, TBADT abstracts hydrogen atoms from the C-H group to form alkyl radicals, which then undergo radical addition reactions with the vinylphosphine cations to generate phosphorus ylide precursors, achieving a yield as high as 99%. This invention utilizes photoreaction to prepare phosphorus ylide precursors, employing inexpensive and readily available raw materials, simple operation, mild reaction conditions, safe conditions, high synthesis yield, and few side reactions. It represents an economical and environmentally friendly synthetic route, providing a new pathway for the synthesis of phosphorus ylide precursors and is suitable for industrial production.

Description

Technical Field

[0001] This invention relates to the field of organic chemical synthesis, and more particularly to a method for preparing phosphorus ylide precursor compounds by functionalization of CH. Background Technology

[0002] Phosphorus ylidees are an important class of organic synthetic intermediates, with the Wittig reaction being a typical representative. Phosphorus ylidees can be obtained by deprotonation of phosphorus ylide precursors under strongly basic conditions; therefore, the development of synthesis techniques for phosphorus ylide precursors is of great significance to the field of organic synthesis. Phosphorus ylide precursors are usually prepared from triarylphosphine and alkyl halides, and can also be obtained through the Michael addition reaction of trivalent phosphine nucleophiles with activated alkenes. Existing methods for synthesizing phosphorus ylidees are limited and cannot meet the diverse transformation needs of modern organic synthesis, necessitating the development of novel and efficient synthetic methods for phosphorus ylide precursors. The activation and transformation of inert CH4 are favored by chemists due to their atom economy and synthetic step economy. This invention develops a hydrogen atom-snap strategy to generate highly reactive organic radicals from alkanes or aldehydes, which then undergo radical addition reactions with alkenylphosphine cations to obtain phosphorus ylide precursors. This method offers high yield, good selectivity, few byproducts, and advantages such as high atom economy and high synthetic efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preparing phosphorus ylide precursor compounds, so as to solve the problems of limited existing methods for synthesizing phosphorus ylide precursors, complex operation, and significant environmental hazards.

[0004] This invention provides a method for preparing phosphorus ylide precursor compounds.

[0005]

[0006] In a first aspect, the present invention provides a method for preparing phosphorus ylide precursors by reacting cycloalkanes with vinylphosphine cations, comprising:

[0007] Phosphorus ylide precursor compounds were prepared by reacting vinylphosphine cations with cycloalkanes via visible light photocatalytic radical addition reactions in the presence of a photocatalyst.

[0008]

[0009] Wherein, R is any one of hydrogen, methyl, methoxy, or fluorine groups, and n is 1-6.

[0010] Preferably, the reaction is carried out under illumination, and the illumination wavelength can be 440nm, 427nm, 390nm, or 370nm, with 370nm being the preferred choice.

[0011] Preferably, the reaction is carried out in an organic solvent system, which can be any one of chloroform, dichloromethane, methanol, acetonitrile, or benzonitrile, with acetonitrile being the preferred choice.

[0012] Preferably, the molar ratio of vinylphosphine cation, cycloalkane, and photosensitizer is 1:10:0.03.

[0013] Preferred, vinylphosphine cation compounds

[0014] Wherein, R is any one of methoxy, fluorine, methyl or hydrogen, preferably methyl, and the substitution at each site is either adjacent, meta or para, preferably adjacent.

[0015] Preferably, the visible light catalytic radical addition reaction refers to the reaction under visible light irradiation for a reaction time of more than 12 hours.

[0016] Secondly, the present invention provides a method for preparing phosphorus ylide precursors by reacting aldehyde compounds with vinylphosphine cations, comprising:

[0017] Phosphorus ylide precursors were prepared by reacting vinylphosphine cations with aldehydes via visible light-catalyzed radical addition reaction under the action of photocatalyst TBADT.

[0018]

[0019] Wherein, R is any one of methoxy, fluorine, methyl or hydrogen, preferably methyl, wherein the substitution at each site is either ortho, meta or para, preferably ortho, and R1 is alkyl, aryl or heterocyclic.

[0020] Preferably, the reaction is carried out in an organic solvent system, which can be any one of chloroform, dichloromethane, methanol, acetonitrile, or benzonitrile, with acetonitrile being the preferred choice.

[0021] Preferably, the molar ratio of vinylphosphine cation, aldehyde, and photosensitizer is 1:2:0.03.

[0022] Preferably, the reaction is carried out under illumination, and the illumination wavelength can be 440nm, 427nm, 390nm, or 370nm, with 370nm being the preferred wavelength.

[0023] Preferably, the visible light catalytic radical addition reaction refers to the reaction under visible light irradiation for a reaction time of more than 12 hours.

[0024] Compared with the prior art, the technical advantages of the present invention are as follows:

[0025] This invention uses inexpensive triarylphosphine as a starting material to generate vinylphosphine cations and cycloalkanes or aldehydes through cracking. Under the action of the photosensitizer TBADT, phosphorus ylide precursor compounds are synthesized directly through a free radical addition reaction catalyzed by visible light. Aldehydes with different charged groups can all be added to phosphate salts, with yields reaching over 99%. In particular, only 2 equivalents of aldehyde compounds are needed for complete reaction, which is a significant improvement over previous methods. Moreover, the reaction conditions are simple and mild, the starting materials are readily available, the reaction is highly efficient, and the production cost is low, making it suitable for industrial production. Attached Figure Description

[0026] The technical solution and other beneficial effects of the present invention will become apparent from the following detailed description of specific embodiments of the invention, in conjunction with the accompanying drawings.

[0027] Figure 1 The NMR spectrum of tris(1-methylphenyl)(2-cyclohexylethyl)bromophosphate as described in Example 1 of the present invention;

[0028] Figure 2 The NMR spectrum of tris(1-methylphenyl)(2-cycloheptaethyl)bromophosphate as described in Example 2 of the present invention;

[0029] Figure 3 The NMR spectrum of tris(1-methylphenyl)(3-oxy-3-phenylpropyl)bromophosphide as described in Example 3 of the present invention;

[0030] Figure 4 The NMR spectrum of tris(1-methylphenyl)(3-oxy-3-p-methylphenylpropyl)bromophosphide as described in Example 4 of the present invention;

[0031] Figure 5 The NMR spectrum of tris(1-methylphenyl)(3-oxy-3-(3,4-dimethylphenylpropyl))bromophosphate described in Example 5 of the present invention;

[0032] Figure 6 The NMR spectrum of tris(1-methylphenyl)(3-oxy-4-methoxyphenylpropyl)bromophosphide as described in Example 6 of the present invention;

[0033] Figure 7 The NMR spectrum of tris(1-methylphenyl)(3-oxy-3-ethylpropyl)bromophosphide as described in Example 7 of the present invention;

[0034] Figure 8 The NMR spectrum of tris(1-methylphenyl)(3-oxy-3-hexylpropyl)bromophosphate as described in Example 8 of the present invention;

[0035] Figure 9The NMR spectrum is shown for the tris(1-methylphenyl)(2,2-dimethylpropyl)bromophosphide salt described in Example 9 of the present invention.

[0036] Figure 10 The NMR spectra of tris(1-methylphenyl)(2-cyclohexylethyl)bromophosphide and tris(1-methylphenyl)(3-oxy-3-cyclohexylpropyl)bromophosphide as described in Example 10 of the present invention.

[0037] Figure 11 The NMR spectroscopy for comparing the amount of propionaldehyde added as described in Example 7 of the present invention shows that the reaction yield reached 92% for both amounts. Figure 11 (Left) When the amount of propionaldehyde added is 5 equivalents, the yield is 33%. Figure 11 right). Detailed Implementation

[0038] The present invention will be further described in detail below through specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above-described invention are still within the scope of protection of the present invention.

[0039] It should be noted that terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity of description and are not intended to limit the scope of implementation. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of implementation of this invention.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0041] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0042] As used herein, the term “about” is used to provide for the flexibility and imprecision associated with a given term, measure, or value. Those skilled in the art can readily determine the degree of flexibility for a particular variable.

[0043] As used herein, the term “at least one of…” is intended to be synonymous with “one or more of…”. For example, “at least one of A, B, and C” explicitly includes only A, only B, only C, and combinations thereof.

[0044] This invention provides a tetravalent phosphine salt compound and its preparation method. Detailed descriptions follow. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments. Furthermore, in the description of this invention, various embodiments may be presented in the form of a range; it should be understood that the description in range format is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the invention; therefore, it should be considered that the range description specifically discloses all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 specifically discloses sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 5, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any referenced number (fraction or integer) within the indicated range.

[0045] Example 1

[0046] To a 10 mL Shrek tube, add 41 mg (0.1 mmol) of tris(1-methylphenyl)-1-enbromophosphine, 84 mg (1 mmol) of cyclohexane, 0.03 mmol of TBADT, and 2 mL of acetonitrile. Irradiate the mixture at room temperature for 18 hours to allow for complete reaction. After the reaction, add 100 mg of 200-300 mesh silica gel, stir well, and then separate by column chromatography using methanol:dichloromethane in a 1:10 solvent ratio to obtain 46 mg of the phosphorus ylide precursor compound, tris(1-methylphenyl)(2-cyclohexylethyl)bromophosphine, in 94% yield. 1 H NMR(500MHz,Chloroform-d)δ7.74(td,J=7.1,2.1Hz,3H),7.58–7.47(m,9H),3.37(q,J=10.0Hz,2H),2.24 (s,9H),1.81–1.74(m,2H),1.69–1.60(m,4H),1.34–1.19(m,4H),1.10(m,1H),0.86(m,J=12.4,6.0Hz,2H). 13CNMR(125MHz,Chloroform-d)δ143.18(d,J=8.4Hz),135.48(d,J=2.9Hz),134.41(d,J=11.3Hz),134.01(d,J=11.0Hz),128.00(d,J =12.7Hz), 115.97 (d, J = 81.9Hz), 38.07 (d, J = 15.2Hz), 32.70, 32.12, 25.91 (d, J = 38.0Hz), 22.84 (d, J = 4.2Hz), 22.23 (d, J = 50.0Hz). 31 P NMR(202MHz,Chloroform-d)δ26.58.

[0047] Its proton NMR spectrum is as follows Figure 1 As shown, the NMR spectrum of tris(1-methylphenyl)(2-cyclohexylethyl)bromophosphate, including its shape, signal, and noise, reflects that the target product of tris(1-methylphenyl)(2-cyclohexylethyl)bromophosphate has extremely high purity, and no other organic impurities are generated during the preparation process.

[0048] Example 2

[0049] The rest is the same as in Example 1, except that 10 mmol of cycloheptane was added to the pressure-resistant tube to obtain 47 mg of tris(1-methylphenyl)(2-cycloheptylethyl)bromophosphide, with a yield of 80%. 1 H NMR(500MHz,Chloroform-d)δ7.73(td,J=8.1,7.2,2.5Hz,3H),7.55–7.46(m,9H),3.31(q,J=10.0Hz,2H),2.22(s,9H),1.81(td,J=6.3,3 .2Hz,1H),1.71(ddd,J=13.8,7.2,4.0Hz,2H),1.59–1.51(m,4H),1.46–1.37(m,4H),1.31(d,J=11.0Hz,2H),1.13(dh,J=12.8,2.7Hz,2H). 13 C NMR(125MHz,Chloroform-d)δ143.14(d,J=8.7Hz),135.47(d,J=3.0Hz),134.39(d,J=11.3Hz),134.00(d,J=11.0Hz),12 7.98(d,J=12.5Hz),115.95(d,J=82.1Hz),39.77(d,J=14.3Hz),33.94,32.55,28.07,25.82,22.81(d,J=4.1Hz),22.46.31 P NMR(202MHz,Chloroform-d)δ26.51.

[0050] Its proton NMR spectrum is as follows Figure 2 As shown, the NMR spectrum of tris(1-methylphenyl)(2-cycloheptaethyl)bromophosphate, including its shape, signal, and noise, also reflects that the tris(1-methylphenyl)(2-cycloheptaethyl)bromophosphate has extremely high purity and that no other organic impurities are generated during its preparation.

[0051] Example 3

[0052] The rest is the same as in Example 1, except that 2 mmol of benzaldehyde was added to the pressure-resistant tube to obtain 43 mg of tris(1-methylphenyl)(3-oxy-3-phenylpropyl)bromophosphine, with a yield of 83%. 1 H NMR(500MHz,Chloroform-d)δ7.79–7.74(m,2H),7.69(dd,J=14.9,7.8Hz,3H),7.63(tt,J=7.6,1.7Hz,3H),7.49(td,J= 8.0,2.6Hz,3H),7.44–7.38(m,4H),7.29(t,J=7.7Hz,2H),4.02–3.92(m,2H),3.55(dt,J=15.0,6.7Hz,2H),2.20(s,9H). 13 C NMR(126MHz,Chloroform-d)δ195.38(d,J=8.8Hz),143.09(d,J=8.9Hz),135.23(d,J=2.6Hz),135.17(d,J=5.8Hz),133.76(d,J=11.0Hz),133.49 ,128.47,128.23,127.84(d,J=12.8Hz),115.86(d,J=82.4Hz),33.18(d, J=3.1Hz), 22.82(d,J=4.1Hz), 17.87(d,J=54.5Hz), 13.50(d,J=23.4Hz). 31 P NMR(202MHz,Chloroform-d)δ30.30.

[0053] Its proton NMR spectrum is as follows Figure 3 As shown, the morphology, signal, and noise of the NMR spectrum of tris(1-methylphenyl)(3-oxy-3-phenylpropyl)bromophosphide also reflect that the phosphine salt of tris(1-methylphenyl)(3-oxy-3-phenylpropyl)bromophosphide has extremely high purity, and no other organic impurities are generated during the preparation process.

[0054] Example 4

[0055] The rest is the same as in Example 1, except that 2 mmol of p-methylbenzaldehyde was added to the pressure-resistant tube to obtain 45 mg of tris(1-methylphenyl)(3-oxy-3-p-methylphenylpropyl)bromophosphine, with a yield of 85%. 1 H NMR(500MHz,Chloroform-d)δ7.71–7.61(m,8H),7.50(td,J=7.8,2.7Hz,3H),7.42(t,J=6.4Hz,3H),7.1 1(d,J=7.8Hz,2H),3.96(dt,J=12.8,7.0Hz,2H),3.48(dt,J=14.6,6.8Hz,2H),2.28(s,3H),2.21(s,9H). 13 C NMR(125MHz,Chloroform-d)δ194.88,144.61,143.14(d,J=8.9Hz),135.27(d,J=2.8Hz),135.18,133.81(d,J=11.1Hz),132.73,129.22,128.41,127.90

[0056] (d,J=12.7Hz),115.96(d,J=82.1Hz),32.99,22.85(d,J=4.1Hz),21.55,18.01(d,J=

[0057] 54.5Hz). 31 P NMR(202MHz,Chloroform-d)δ30.64.

[0058] Its proton NMR spectrum is as follows Figure 4 As shown, the NMR spectrum of tris(1-methylphenyl)(3-oxy-3-p-methylphenylpropyl)bromophosphide reflects its extremely high purity, as well as the presence of no other organic impurities during its preparation.

[0059] Example 5

[0060] The rest is the same as in Example 1, except that 2 mmol of 3,4-dimethylbenzaldehyde was added to the pressure-resistant tube to obtain 40 mg of tris(1-methylphenyl)(3-oxy-3-(3,4-dimethylphenylpropyl))bromophosphide, with a yield of 73%. 1H NMR(500MHz,Chloroform-d)δ7.70(dd,J=15.0,7.8Hz,3H),7.65(tt,J=7.6,1.7Hz,3H),7.55(d,J=2.0Hz,1H),7.54–7.48(m,4H),7.4 2(dd,J=7.7,5.3Hz,3H),7.06(d,J=7.9Hz,1H),3.97(dt,J=11.2,6.8Hz,2H),3.49(dt,J=14.8,6.7Hz,2H),2.22(s,9H),2.19(s,6H). 13 CNMR(125MHz,Chloroform-d)δ195.12(d,J=8.9Hz),143.39,143.19(d,J=8.8Hz ),136.97,135.34(d,J=11.6Hz),135.24(d,J=2.9Hz),133.82(d,J=11.1Hz),13 3.18,129.52(d,J=65.1Hz),127.93(d,J=12.7Hz),126.09,116.39,115.74,33. 07(d,J=3.2Hz), 22.93(d,J=4.2Hz), 19.76(d,J=47.8Hz), 18.03(d,J=54.6Hz). 31 P NMR(202MHz,Chloroform-d)δ30.29.

[0061] Its proton NMR spectrum is as follows Figure 5 As shown, the NMR spectrum of tris(1-methylphenyl)(3-oxy-3-(3,4-dimethylphenylpropyl))bromophosphate, including its shape, signal, and noise, also reflects that the tris(1-methylphenyl)(3-oxy-3-(3,4-dimethylphenylpropyl))bromophosphate has extremely high purity, and no other organic impurities are generated during its preparation.

[0062] Example 6

[0063] The rest is the same as in Example 1, except that 2 mmol of 4-methoxybenzaldehyde was added to the pressure-resistant tube to obtain 46 mg of tris(1-methylphenyl)(3-oxy-4-methoxyphenylpropyl)bromophosphide, with a yield of 85%. 1H NMR(500MHz,Chloroform-d)δ7.89–7.84(m,2H),7.75(dd,J=15.0,7.9Hz,3H),7.67(m,J=7.7,1.7Hz,3H),7.54(m,J=9.4,7.6,2.2H z,3H),7.48–7.41(m,3H),6.86–6.81(m,2H),3.99(dt,J=11.2,6.8Hz,2H),3.79(s,3H),3.56(dt,J=14.5,6.7Hz,2H),2.24(s,9H). 13 C NMR(125MHz,Chloroform-d)δ193.73(d,J=9.1Hz),163.95,143.16(d,J=8.8Hz),135.37(d,J=11.7Hz),135.27(d,J=3.0Hz),133.82(d,J=11.1 Hz), 130.90, 128.25, 127.99 (d, J = 12.7Hz), 116.07 (d, J = 82.3Hz), 113.79, 55.49, 32.83 (d, J = 3.1Hz), 22.91 (d, J = 4.1Hz), 18.22 (d, J = 54.2Hz). 31 P NMR(202MHz,Chloroform-d)δ30.47.

[0064] Its proton NMR spectrum is as follows Figure 6 As shown, the NMR spectrum of tris(1-methylphenyl)(3-oxy-4-methoxyphenylpropyl)bromophosphate, including its shape, signal, and noise, also reflects that the tris(1-methylphenyl)(3-oxy-4-methoxyphenylpropyl)bromophosphate has extremely high purity and that no other organic impurities were generated during its preparation.

[0065] Example 7

[0066] The rest is the same as in Example 1, except that 2 mmol of propionaldehyde was added to the pressure-resistant tube to obtain 44 mg of tris(1-methylphenyl)(3-oxy-3-ethylpropyl)bromophosphine, with a yield of 93%. 1 H NMR(500MHz,Chloroform-d)δ7.77–7.69(m,6H),7.60–7.54(m,3H),7.49(dd,J=7.7,5.3Hz,3H),3.88 (dt,J=12.3,7.1Hz,2H),3.04–3.00(m,2H),2.50(q,J=7.3Hz,2H),2.26(s,9H),0.92(t,J=7.3Hz,3H). 13CNMR(125MHz,Chloroform-d)δ206.98,143.13(d,J=8.8Hz),135.24,135.18(d,J=8.5Hz),133.75(d,J=11.0Hz),127 .91(d,J=12.7Hz), 115.95(d,J=82.3Hz), 36.22(d,J=3.6Hz), 35.98, 22.76(d,J=4.1Hz), 17.85(d,J=54.3Hz), 7.40. 31 P NMR(202MHz,Chloroform-d)δ29.93.

[0067] Its proton NMR spectrum is as follows Figure 7 As shown, the NMR spectrum of tris(1-methylphenyl)(3-oxy-3-ethylpropyl)bromophosphide, including its shape, signal, and noise, also reflects that the tris(1-methylphenyl)(3-oxy-3-ethylpropyl)bromophosphide has extremely high purity and that no other organic impurities are generated during its preparation.

[0068] Example 8

[0069] The rest is the same as in Example 1, except that 2 mmol of heptanal was added to the pressure-resistant tube to obtain 52 mg of tris(1-methylphenyl)(3-oxy-3-hexylpropyl)bromophosphide, with a yield of 99%. 1 H NMR(500MHz,Chloroform-d)δ7.73(dq,J=12.6,7.0,6.1Hz,6H),7.57(td,J=7.7,2.8Hz,3H),7.48(dd,J=7.8,5.2Hz,3H),3.89(dq,J=13.0,6.1Hz,2 H),3.11–2.96(m,2H),2.45–2.38(m,2H),2.28–2.23(m,9H),1.37(p,J=7. 5Hz,2H),1.20(q,J=7.1Hz,2H),1.17(m,4H),0.82(td,J=7.2,3.0Hz,3H). 13C NMR(125MHz,Chloroform-d)δ206.40(d,J=9.5Hz),143.12(d,J=8.8Hz),135.23,135.16(d,J=3.3Hz),133.70(d,J=11.0Hz),127.8 3(d,J=12.8Hz),115.93(d,J=82.3Hz),42.53,36.53,31.32,28.40,23.27,22.75(d,J=4.1Hz),22.23,17.50(d,J=54.2Hz),13.83. 31 PNMR(202MHz,Chloroform-d)δ30.17.

[0070] Its proton NMR spectrum is as follows Figure 8 As shown, the NMR spectrum of tris(1-methylphenyl)(3-oxy-3-hexylpropyl)bromophosphide, including its shape, signal, and noise, also reflects its extremely high purity, and that no other organic impurities were generated during its preparation.

[0071] Example 9

[0072] The rest is the same as in Example 1, except that 2 mmol of pentylaldehyde was added to the pressure-resistant tube to obtain 44 mg of the decarbonylation product tris(1-methylphenyl)(2,2-dimethylpropyl)bromophosphide, with a yield of 94%. 1 H NMR(500MHz,Chloroform-d)δ7.78(tt,J=7.6,1.7Hz,3H),7.61–7.53(m,7H),7.50(ddd,J=14.3,7. 9,1.4Hz,3H),3.20(td,J=11.8,7.0Hz,2H),2.25(d,J=1.2Hz,9H),1.33–1.26(m,2H),1.02(s,9H). 13 CNMR (125MHz, Chloroform-d) δ 143.22 (d, J = 8.5Hz), 135.77 (d, J = 3.0Hz), 134.28 (dd, J = 11.2, 7.6Hz), 128.15 (d, J = 12. 6Hz), 115.85 (d, J = 82.1Hz), 38.13 (d, J = 5.3Hz), 31.47 (d, J = 14.6Hz), 28.85, 22.87 (d, J = 4.1Hz), 20.66 (d, J = 51.7Hz).

[0073] Its proton NMR spectrum is as follows Figure 9As shown, the NMR spectrum of tris(1-methylphenyl)(2,2-dimethylpropyl)bromophosphide, including its shape, signal, and noise, also reflects the extremely high purity of the tris(1-methylphenyl)(2,2-dimethylpropyl)bromophosphide, and that no other organic impurities were generated during its preparation.

[0074] Example 10

[0075] The rest is the same as in Example 1, except that 2 mmol of cyclohexylaldehyde was added to the pressure-resistant tube to obtain the decarbonylated product tris(1-methylphenyl)(2-cyclohexylethyl)bromophosphate in 19% yield, and the non-decarbonylated product tris(1-methylphenyl)(3-oxy-3-cyclohexylpropyl)bromophosphate in 73% yield, for a total yield of 92%. 1 H NMR(500MHz,Chloroform-d)δ7.76–7.64(m,7H),7.56–7.48(m,5H),7.44(dd,J=7.6,5.3Hz,3H),3.88(dt, J=12.0,6.6Hz,2H),3.34(q,J=10.0,9.6Hz,0H),3.11(dt,J=15.3,6.7Hz,2H),2.37–2.26(m,1H),2.22(s, 11H),1.80–1.72(m,1H),1.64(td,J=16.1,14.1,8.3Hz,1H),1.55(dtt,J=13.3,9.7,4.2Hz,5H),1.31–1.2 0(m,2H),1.12(tdd,J=15.2,12.3,6.1Hz,3H),1.02(dt,J=12.0,9.4Hz,3H),0.85(dd,J=12.0,3.4Hz,0H).

[0076] Its proton NMR spectrum is as follows Figure 10 As shown, the extremely high purity of the bromophosphate can also be seen from the shape, signal, and noise of its NMR spectrum, and no other organic impurities were generated during the preparation process.

[0077] The yields of the target products prepared in the above embodiments are listed in Table 1.

[0078] Table 1

[0079]

[0080]

[0081] The above embodiments provide a method for preparing phosphorus ylide precursor compounds. Using inexpensive triphenylphosphine as a starting material, olefins and cycloalkyl groups or aldehydes are synthesized. Acetonitrile is used as a solvent, and TBADT is used as a photocatalyst. Under visible light catalysis, a free radical addition reaction is carried out to synthesize phosphorus ylide precursor compounds. This method can prepare a wide range of substrates and has a high yield. As shown in Table (1), the reaction can be adapted to a variety of substrates.

[0082] The embodiments of the present invention provide a method for preparing phosphorus ylide precursor compounds, which uses inexpensive triphenylphosphine as a starting material to synthesize olefins and cycloalkyl or aldehydes, uses acetonitrile as a solvent and TBADT as a photocatalyst, and carries out free radical addition reactions under visible light catalysis. The yields can reach 70%-99% or more. Moreover, the reaction conditions are simple and mild, the starting materials are readily available, the reaction is highly efficient, and the production cost is low, making it suitable for industrial production.

[0083] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0084] The preparation method of a phosphorus ylide precursor compound provided by the embodiments of the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the technical solution and core idea of ​​the present invention. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing phosphorus ylide precursor compounds by functionalization of CH, characterized in that, include: Phosphorus ylide precursor compounds are prepared by radical addition reactions of olefin phosphorus salts with aldehydes or cycloalkanes under the action of TBADT photocatalyst, with the following general formula: Wherein, R is any one of hydrogen, methyl, methoxy, or fluorine groups.

2. The method for preparing the phosphorus ylide precursor according to claim 1, characterized in that, When the substrate of the reaction is a cycloalkanes: Wherein, R is any one of methoxy, fluorine, methyl or hydrogen; and the substitution at each site is ortho, meta or para, and n is 1-6.

3. The method for preparing the phosphorus ylide precursor according to claim 2, characterized in that, R stands for methyl group, and site substitution is selected from adjacent positions.

4. The method for preparing the phosphorus ylide precursor according to claim 2, characterized in that, The molar ratio of olefin phosphate, cycloalkanes, and photocatalyst is 1:10:0.

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5. The method for preparing the phosphorus ylide precursor according to claim 1, characterized in that, When the substrate of the reaction is an aldehyde: Wherein, R is any one of methoxy, fluorine, methyl or hydrogen; wherein, the substitution positions at each site are ortho, meta or para, and R1 is alkyl, aryl or heterocyclic.

6. The method for preparing the phosphorus ylide precursor according to claim 5, characterized in that, R stands for methyl group, and site substitution is selected from adjacent positions.

7. The method for preparing the phosphorus ylide precursor according to claim 5, characterized in that, The molar ratio of olefin phosphate salt, aldehyde, and photocatalyst is 1:2:0.

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8. The method for preparing the phosphorus ylide precursor according to claim 2 or 5, characterized in that, The reaction was carried out under the illumination of 10W LEDs with a wavelength of 370nm.

9. The method for preparing the phosphorus ylide precursor according to claim 2 or 5, characterized in that, Various substituents are adapted to olefin phosphate compounds. The hydrogen atom transfer reagent is TBADT tungstate, and the solvent is highly polar acetonitrile.

10. The method for preparing the phosphorus ylide precursor according to claim 2 or 5, characterized in that, Visible light-catalyzed free radical addition reaction refers to a reaction that takes place under visible light irradiation for more than 12 hours.

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