A method for palladium-catalyzed linear selective hydroformylation of olefins

Abstract

This invention belongs to the field of organic synthesis, and specifically relates to a palladium-catalyzed method for the selective hydroformylation of linear olefins. Using olefins of different structures as raw materials, N-formylsaccharin as the carbonyl source, formic acid as the hydrogen source, palladium trifluoroacetate as the catalyst, and 1,3-bis(diphenylphosphine)propane (dppp) as the ligand, a series of linear aldehyde compounds can be obtained. This method uses readily available raw materials, operates under mild conditions, and is simple to perform, showing great promise for future applications.

Description

Technical Field

[0001] This invention belongs to the field of organic synthesis, and specifically relates to a palladium-catalyzed method for selective hydroformylation of linear olefins using N-formylsaccharin as a carbonyl source. Background Technology

[0002] Aldehydes are crucial and fundamental compounds, capable of undergoing a wide range of chemical transformations. However, many high-value aldehydes are difficult to obtain through conventional methods. The regioselective hydroformylation of alkenes offers a highly attractive approach due to its high atom economy and practicality. Traditionally, olefin hydroformylation has used CO / H2 as the carbonyl and hydrogen sources, but the toxicity and hazards of these gases make this method inconvenient to use. It typically requires strict adherence to procedures, specialized equipment, and highly skilled operators, and carries inherent risks. Therefore, we developed a palladium-catalyzed olefin hydroformylation system based on HCOOH / Ac2O. This system exhibits good selectivity for aryl alkenes, but lower selectivity for alkyl alkenes and a limited substrate range. Consequently, we conducted in-depth research on the regioselective hydroformylation of alkyl alkenes and successfully implemented this process. This method overcomes the limitations of our previously developed formic acid system and plays a vital role in organic synthesis and natural product synthesis. Summary of the Invention

[0003] The purpose of this invention is to provide a palladium-catalyzed method for the regioselective hydroformylation of olefins. Palladium trifluoroacetate (Pd(TFA)) is used. 2） Using 1,3-bis(diphenylphosphine)propane (dppp) as a catalyst, various olefin compounds as substrates, N-formylsaccharin as a carbonyl source, and formic acid as a hydrogen source, a linear selective hydroformylation reaction of olefins is carried out.

[0004] This invention provides a method for palladium-catalyzed linear selective hydroformylation of olefins, comprising the following steps:

[0005] In an inert atmosphere, the olefin shown in Formula I, palladium trifluoroacetate, dppp, N-formyl saccharin, tetrabutylammonium iodide, 4Å molecular sieve, and formic acid were reacted in acetonitrile. After the reaction was completed, the aldehyde shown in Formula II was purified by column chromatography.

[0006]

[0007] In Formulas I and II, R is an alkyl group, phthalimide, or triphenylsilyl group, and the alkyl group may contain substituents of different halogen atoms or groups.

[0008] Furthermore, the molar amount of palladium trifluoroacetate is 0.0475 to 0.0525 times the molar amount of the olefin shown in Formula I, the molar amount of dppp is 0.095 to 0.105 times the molar amount of the olefin shown in Formula I, the molar amount of N-formylsaccharin is 1.9 to 2.1 times the molar amount of the olefin shown in Formula I, the molar amount of formic acid is 1.045 to 1.155 times the molar amount of the olefin shown in Formula I, and the molar amount of tetrabutylammonium iodide is 0.024 to 0.026 times the molar amount of the olefin shown in Formula I.

[0009] Furthermore, the olefin shown in Formula I has a concentration of 1.0 mol / L in a mixture of palladium trifluoroacetate, dppp, N-formylsaccharin, tetrabutylammonium iodide, 4Å molecular sieve, formic acid and acetonitrile.

[0010] Furthermore, in the reaction step, the time is 23-25 ​​hours and the temperature is 75-85 degrees Celsius. o C.

[0011] Furthermore, in the column chromatography step, the column packing solvent is petroleum ether; the eluent is petroleum ether and ethyl acetate; and the column packing material is 300-400 mesh silica gel with a diameter of 3 cm × height of 20 cm.

[0012] Specifically, the compound represented by Formula II is any one of the following compounds:

[0013] .

[0014] This invention utilizes alkyl olefins, substituted alkyl olefins, phthalimide olefins, or triphenylsilyl olefins as raw materials, palladium trifluoroacetate as a catalyst, dppp as a ligand, N-formylsaccharin as a carbonyl source, and formic acid as a hydrogen source to effectively achieve the linear selective hydroformylation reaction of olefins. This method features readily available raw materials, mild reaction conditions, and simple operation. Detailed Implementation

[0015] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments. Unless otherwise specified, the methods described are conventional methods. Unless otherwise specified, the raw materials are all available from publicly available commercial sources. In the column chromatography steps of the following embodiments, the packing material used in the chromatography column is 300-400 mesh silica gel, with dimensions of 3cm in diameter x 20cm in height.

[0016] This invention uses olefins with different structures as raw materials (0.50 mmol molar amount), palladium trifluoroacetate as catalyst, dppp as ligand, N-formylsaccharin as carbonyl source, and formic acid as hydrogen source to investigate the substrate-wide applicability of this regioselective hydroformylation catalytic system. Specific embodiments are as follows:

[0017] Example 1. Aldehyde (see structural formula II-a):

[0018]

[0019] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel. 0.50 mL of the first organic solvent MeCN, 1-dodecene Ia (0.0842 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol) were added. The vessel was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a pale yellow solid II-a (0.0647 g, 65% yield, straight-chain / branched selectivity l / b = 14:1).

[0020] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.76 (t, J = 2.0 Hz, 1H), 2.41 (td, J = 7.6, 2.0 Hz, 2H), 1.67-1.57 (m, 2H), 1.33-1.23 (m, 18H), 0.88(t, J = 6.8 Hz, 3H); 13 C NMR (100 MHz, CDCl3) δ 203.1, 44.1, 32.1, 29.8, 29.76, 29.6, 29.5, 29.3, 22.9, 22.3, 14.3.

[0021] The synthesized compound was identified as the target compound, aldehyde II-a, based on structural analysis.

[0022] Example 2. Aldehyde (see structural formula II-b):

[0023]

[0024] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, followed by 0.50 mL of the first organic solvent MeCN, styrene Ib (0.0731 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The vessel was then charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a pale yellow liquid (0.0495 g, 56% yield, l / b = 18:1).

[0025] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.76 (t, J = 1.6 Hz, 1H),7.31-7.25 (m, 2H), 7.21-7.15 (m, 3H), 2.61 (t, J = 7.6 Hz, 2H), 2.42 (td, J =7.6, 1.6 Hz, 2H), 1.71-1.60 (m, 4H), 1.42-1.32 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.9, 142.5, 128.5, 128.4, 125.9, 44.0, 35.8, 31.3, 28.9, 22.1.

[0026] The synthesized compound was identified as the target compound, aldehyde II-b, based on structural analysis.

[0027] Example 3. Aldehyde (see structural formula II-c):

[0028]

[0029] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel. 0.50 mL of the first organic solvent MeCN, p-methylbutene Ic (0.0731 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol) were added. The mixture was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless liquid II-c (0.0583 g, 66% yield, l / b = 16:1).

[0030] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.75 (t, J = 2.0 Hz, 1H),7.11-7.04 (m, 4H), 2.60 (t, J = 7.2 Hz, 2H), 2.44 (td, J = 6.8, 1.6 Hz, 2H),2.32 (s, 3H), 1.70-1.62 (m, 4H); 13 C NMR (100 MHz, CDCl3) δ 202.8, 139.0,135.5, 129.2, 128.4, 43.9, 35.3, 31.2, 21.8, 21.2.

[0031] The synthesized compound was identified as the target compound, aldehyde II-c, based on structural analysis.

[0032] Example 4. Aldehyde (see structural formula II-d):

[0033]

[0034] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, along with 0.50 mL of the first organic solvent MeCN, 2-bromophenylbutene Id (0.1056 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The vessel was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless liquid II-d (0.0597 g, 50% yield, l / b > 20:1).

[0035] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.78 (t, J = 1.6 Hz, 1H), 7.52 (dd, J = 8.0, 1.2 Hz, 1H), 7.26-7.18 (m, 2H), 7.05 (ddd, J = 8.8, 6.8,2.4 Hz, 1H), 2.76 (t, J = 7.6 Hz, 2H), 2.49 (td, J = 6.8, 1.6 Hz, 2H), 1.77-1.61 (m, 4H); 13 C NMR (100 MHz, CDCl3) δ 202.7, 141.4, 133.0, 130.5, 127.8,127.6, 124.6, 43.9, 36.0, 29.5, 21.9.

[0036] The synthesized compound was identified as the target compound, aldehyde II-d, based on structural analysis.

[0037] Example 5. Aldehyde (see structural formula II-e):

[0038]

[0039] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel. 0.50 mL of the first organic solvent MeCN, 10-undecenal Ie (0.0841 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol) were added. The vessel was purged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless II-e liquid (0.040 g, 40% yield, l / b > 20:1).

[0040] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.76 (t, J = 1.6 Hz, 2H), 2.42 (td, J = 7.2, 1.6 Hz, 4H), 1.68-1.58 (m, 4H), 1.34-1.25 (m, 12H); 13 C NMR (100 MHz, CDCl3) δ 203.2, 44.1, 29.5, 29.3, 22.2.

[0041] The synthesized compound was identified as the target compound, aldehyde II-e, based on structural analysis.

[0042] Example 6. Aldehyde (see structural formula II-f):

[0043]

[0044] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, followed by 0.50 mL of the first organic solvent MeCN, octyl 1-butenoate If (0.0992 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The mixture was charged with Ar and reacted at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless liquid II-f (0.0543 g, 48% yield, l / b = 15:1).

[0045] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.77 (t, J = 1.2 Hz, 1H), 4.06 (t, J = 6.4 Hz, 2H), 2.53 (td, J = 7.2, 1.2 Hz, 2H), 2.36 (t, J = 7.2Hz, 2H), 2.00-1.90 (m, 2H), 1.66-1.56 (m, 2H), 1.38-1.22 (m, 10H), 0.88 (t, J = 7.2 Hz, 3H); 13 C NMR (100 MHz, CDCl3) δ 201.7, 173.1, 64.8, 43.1, 33.3,31.9, 29.33, 29.3, 28.7, 26.0, 22.8, 17.5, 14.2.

[0046] The synthesized compound was identified as the target compound, aldehyde II-f, based on structural analysis.

[0047] Example 7. Aldehyde (see structural formula II-g):

[0048]

[0049] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, along with 0.50 mL of the first organic solvent MeCN, 1 g of allylbenzene (0.0591 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The vessel was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding II-g of a colorless liquid (0.0398 g, 54% yield, l / b = 9:1).

[0050] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.76 (t, J = 1.6 Hz, 1H),7.32-7.27 (m, 2H), 7.23-7.15 (m, 3H), 2.66 (t, J = 7.6 Hz, 2H), 2.46 (td, J =7.2, 1.6 Hz, 2H), 2.02-1.92 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.5, 141.4, 128.6, 126.3, 43.3, 35.2, 23.8.

[0051] The synthesized compound was identified as the target compound, aldehyde II-g, based on structural analysis.

[0052] Example 8. Aldehyde (see structural formula II-h):

[0053]

[0054] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel. 0.50 mL of the first organic solvent MeCN, 1-allylnaphthalene Ih (0.0841 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol) were added. The mixture was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless liquid II-h (0.0602 g, 61% yield, l / b > 20:1).

[0055] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.79 (t, J = 1.6 Hz, 1H), 8.06 (d, J = 8.4 Hz, 1H), 7.86 (d, J = 8.0 Hz, 1H), 7.73 (d, J = 8.0 Hz, 1H), 7.53 (ddd, J = 8.4, 6.8, 1.6 Hz, 1H), 7.48 (ddd, J = 8.4, 7.2, 1.6 Hz, 1H),7.40 (t, J = 7.2 Hz, 1H), 7.31 (d, J = 6.8 Hz, 1H), 3.13 (t, J = 7.6 Hz, 2H), 2.55 (td, J = 7.2, 1.2 Hz, 2H), 2.16-2.06 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ202.4, 137.5, 134.1, 131.9, 129.0, 127.1, 126.4, 126.1, 125.7, 125.6, 123.8,43.6, 32.3, 23.1.

[0056] The synthesized compound was identified as the target compound, aldehyde II-h, based on structural analysis.

[0057] Example 9. Aldehyde (see structural formula II-i):

[0058]

[0059] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, along with 0.50 mL of the first organic solvent MeCN, nucleoside-derived olefin II (0.2122 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The vessel was then charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a yellow liquid II-i (0.1155 g, 51% yield, l / b > 20:1).

[0060] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.76 (t, J = 1.6 Hz, 1H), 7.35 (d, J = 8.0 Hz, 1H), 5.99 (d, J = 4.8 Hz, 1H), 5.80 (d, J = 8.0 Hz, 1H),5.38-5.29 (m, 2H), 4.38-4.33 (m, 3H), 3.97-3.88 (m, 2H), 2.52-2.46 (m, 2H),2.14 (s, 3H), 2.12 (s, 3H), 2.11 (s, 3H), 1.70-1.63 (m, 4H); 13 C NMR (100 MHz, CDCl3) δ 202.3, 170.3, 169.8, 162.4, 150.9, 137.4, 103.0, 89.0, 79.9, 73.2,70.1, 63.1, 43.6, 40.9, 27.1, 21.0, 20.7, 20.65, 19.5.

[0061] The synthesized compound was identified as the target compound, aldehyde II-i, based on structural analysis.

[0062] Example 10. Carboxylic acid (see structural formula II-j):

[0063]

[0064] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel. 0.50 mL of the first organic solvent MeCN, 1,1-stilbene Ij (0.0901 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol) were added. The mixture was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless liquid II-j (0.047 g, 45% yield, l / b > 20:1).

[0065] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.74 (t, J = 1.6 Hz, 1H), 7.30 (t, J = 7.6 Hz, 4H), 7.25-7.17 (m, 6H), 4.63 (t, J = 7.6 Hz, 1H), 3.18(dd, J = 7.6, 1.6 Hz, 2H); 13 C NMR (100 MHz, CDCl3) δ 201.3, 143.4, 128.9,127.9, 126.9, 49.5, 45.1.

[0066] The synthesized compound was identified as the target compound, aldehyde II-j, based on structural analysis.

[0067] Example 11. Aldehyde (see structural formula II-k):

[0068]

[0069] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formylsaccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, along with 0.50 mL of the first organic solvent MeCN, the steroidal derivative olefin Ik (0.1702 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The mixture was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding II-k as a white solid (0.065 g, 35% yield, l / b > 20:1).

[0070] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.18 (d, J = 8.4 Hz, 1H), 6.71 (dd, J = 8.8, 2.8 Hz, 1H), 6.63 (d, J = 2.4Hz, 1H), 3.77 (s, 3H), 3.23 (s, 3H), 2.90-2.80 (m, 2H), 2.52 (td, J = 6.8,1.2 Hz, 2H), 2.31-2.23 (m, 1H), 2.13 (td, J = 11.2, 4.0 Hz, 1H), 2.05-1.23(m, 15H), 0.95 (s, 3H); 13 C NMR (100 MHz, CDCl3) δ 202.8, 157.6, 138.1, 132.7,126.4, 113.9, 111.6, 87.8, 55.4, 51.5, 51.0, 47.2, 44.5, 43.7, 39.5, 34.8,34.1, 30.3, 30.0, 27.6, 26.7, 23.4, 16.2, 14.0.

[0071] The synthesized compound was identified as the target compound, aldehyde II-k, based on structural analysis.

[0072] Example 12. Aldehyde (see structural formula II-1):

[0073]

[0074] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formyl saccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, followed by 0.50 mL of the first organic solvent MeCN, triphenylsilyl ethylene Il (0.1432 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The mixture was purged with Ar and reacted at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding II-l white solid (0.1049 g, 66% yield, l / b > 20:1).

[0075] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.74 (t, J = 1.6 Hz, 1H),7.55-7.50 (m, 6H), 7.43 (tt, J = 7.2, 1.6 Hz, 3H), 7.40-7.34 (m, 6H), 2.59-2.51 (m, 2H), 1.67-1.60 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.6, 135.7,134.2, 130.0, 128.3, 38.6, 4.9.

[0076] The synthesized compound was identified as the target compound, aldehyde II-l, based on structural analysis.

[0077] Example 13. Aldehyde (see structural formula II-m):

[0078]

[0079] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formyl saccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel, along with 1.0 mL of the first organic solvent MeCN, phthalamide vinylidene Im (0.0866 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol). The mixture was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a white solid II-m (0.043 g, 42% yield, l / b > 20:1).

[0080] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.2 Hz, 1H), 7.85 (dd, J = 5.2, 2.8 Hz, 2H), 7.73 (dd, J = 5.2, 2.8 Hz, 2H), 4.04 (t, J =7.2 Hz, 2H), 2.88 (td, J = 7.2, 1.2 Hz, 2H); 13 C NMR (100 MHz, CDCl3) δ 199.7,168.2, 134.3, 132.1, 123.6, 42.5, 31.8.

[0081] The synthesized compound was identified as the target compound, aldehyde II-m, based on structural analysis.

[0082] Example 14. Aldehyde (see structural formula II-n):

[0083]

[0084] Pd(TFA)₂ (0.0083 g, 0.025 mmol), dppp (0.0206 g, 0.050 mmol), Bu₄NI (0.0046 g, 0.0125 mmol), 4Å molecular sieve (0.010 g), and N-formyl saccharin (0.2112 g, 1.0 mmol) were added to a reaction vessel. 1.0 mL of the first organic solvent MeCN, phthalamidobutene In (0.1006 g, 0.50 mmol), and formic acid (0.0253 g, 0.55 mmol) were added. The mixture was charged with Ar, and the reaction was carried out at 80 °C for 24 h. Column chromatography was performed under the following conditions: the column was packed with petroleum ether, and the eluent was petroleum ether / ethyl acetate, yielding a colorless II-n liquid (0.0458 g, 40% yield, l / b > 20:1).

[0085] The structural verification results are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.76 (t, J = 1.2 Hz, 1H), 7.84 (dd, J = 5.6, 3.2 Hz, 2H), 7.72 (dd, J = 5.2, 3.2 Hz, 2H), 3.71 (t, J =6.8 Hz, 2H), 2.51 (td, J = 7.6, 1.6 Hz, 2H), 1.78-1.63 (m, 4H); 13 C NMR (100MHz, CDCl3) δ 202.1, 168.6, 134.2, 132.2, 123.4, 43.4, 37.6, 28.1, 19.4.

[0086] The synthesized compound was identified as the target compound, aldehyde II-n, based on structural analysis.

Claims

1. A method for the palladium catalyzed linear chain selective hydroformylation of an olefin, characterized in that, The olefin, palladium trifluoroacetate, 1,3-bis(diphenylphosphino)propane, N-formyl saccharin, formic acid, tetrabutylammonium iodide, 4A molecular sieve are reacted in acetonitrile in an inert atmosphere, and after the reaction is completed, a linear aldehyde is obtained by purification; The olefin is any one of the following compounds: 、 、 、 、 、 、 、 、 、 、 ; The linear aldehyde is any one of the following compounds: 。 2. The process for the palladium-catalyzed linear-selective hydroformylation of olefins according to claim 1, characterized in that, The molar amount of the palladium trifluoroacetate is 0.0475-0.0525 times the molar amount of the olefin, the molar amount of the 1,3-bis(diphenylphosphino)propane is 0.095-0.105 times the molar amount of the olefin, the molar amount of the N-formyl saccharin is 1.9-2.1 times the molar amount of the olefin, the molar amount of the formic acid is 1.045-1.155 times the molar amount of the olefin, and the molar amount of the tetrabutylammonium iodide is 0.024-0.026 times the molar amount of the olefin.

3. The method of selective hydroformylation of olefins catalyzed by palladium according to claim 1, characterized in that, The concentration of the olefin in the mixture composed of 1,3-bis(diphenylphosphino)propane, palladium trifluoroacetate, N-formyl saccharin, formic acid, tetrabutylammonium iodide, 4A molecular sieve and acetonitrile is 1.0 mol / L.

4. The process for the palladium-catalyzed linear-selective hydroformylation of olefins according to claim 1, characterized in that, The reaction temperature of the reaction is 75-85 DEG C, and the reaction time is 23-25 hours.

5. The process for the palladium-catalyzed linear-selective hydroformylation of olefins according to claim 1, characterized in that, After the reaction is completed, column chromatography is used for purification, the solvent for column loading is petroleum ether, the eluent is petroleum ether and ethyl acetate, and the filler of the column used is silica gel with a particle size of 300-400 mesh and a specification of diameter 3 cm x height 20 cm.

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