Ring-opening hydroformylation reaction of benzylidene cyclopropane with formic acid as carbonyl source

Abstract

The invention relates to the technical field of organic medicines, and discloses a ring-opening hydroformylation reaction of benzylidene cyclopropane with formic acid as a carbonyl source. The ring-opening hydroformylation reaction of benzylidene cyclopropane comprises the following steps: under the protection of inert gas, proportionally adding benzylidene cyclopropane, formic acid, a metal rhodium salt, a ligand and acetic anhydride into an organic solvent, reacting under mild conditions, preparing gamma and delta unsaturated aldehyde compounds as shown in the following formula after the reaction, and separating a target product after the reaction is completed. According to the method, formic acid is used as a carbonyl source, the method has the advantages of being simple and novel, and a series of gamma and delta unsaturated aldehyde compounds and derivatives thereof can be synthesized with extremely high efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of organic drug synthesis, and in particular to a ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source. Background Art

[0002] Benzylidenecyclopropane is an important class of organic synthesis intermediates. A variety of important organic compounds can be obtained through the functionalization reaction of benzylidenecyclopropane. In addition, γ,δ-unsaturated carbonyl compounds are also extremely widely used in disciplines such as fine chemical industry and pharmaceutical chemistry. As the molecular skeletons of drugs, spices, etc., they play a huge role in people's daily lives (as shown in the figure below).

[0003]

[0004] In previous studies, the hydroformylation reaction of olefins mainly used carbon monoxide as a carbonyl source and hydrogen as a reducing agent. However, carbon monoxide is toxic, hydrogen is flammable and explosive, and most of the reactions need to be carried out under high temperature and high pressure, which limits the application of such reactions in laboratories, the pharmaceutical industry or industry. Therefore, it is of great significance to develop a mild hydroformylation method without carbon monoxide and hydrogen. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: to overcome the deficiencies in the prior art and provide a ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source. The present invention does not involve carbon monoxide and hydrogen, and can successfully achieve the ring-opening hydroformylation reaction of methylenecyclopropane under mild conditions only in the presence of equivalent formic acid, thereby efficiently and highly selectively preparing a series of γ,δ-unsaturated aldehyde compounds.

[0006] The technical solution adopted by the present invention to solve its technical problems is:

[0007] A ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source. Under a nitrogen protection atmosphere, benzylidenecyclopropane, formic acid, metal rhodium salt, phosphine ligand and acetic anhydride are dispersed in an organic solvent and then reacted to obtain a crude product of γ,δ-unsaturated aldehyde; after the reaction is completed, the crude product of γ,δ-unsaturated aldehyde is separated to obtain the target product γ,δ-unsaturated aldehyde.

[0008] The reaction formula of this preparation method is:

[0009]

[0010] Further, the structural formula of the benzylidenecyclopropane is

[0011] Among them, R is one of an alkyl group, a phenyl group, fluorine, chlorine, bromine, trifluoromethyl, naphthalene, and thiophene.

[0012] Further, the molar ratio of the benzylidenecyclopropane, formic acid, metal rhodium salt, phosphine ligand, and acetic anhydride is 1:(1 - 4):(0.001 - 0.05):(0.004 - 0.2):(1 - 4).

[0013] Further, the phosphine ligand is one of PPh3, (o-OMe-Ph)3P, (p-F-Ph)3P, (2-thienyl)3P, (2-furyl)3P, PPh2Cy, PPhCy2, PCy3, (C6F5)3P, dppm, dppb, and dppf. The phosphine ligand is preferably PPh3 (triphenylphosphine), and its structural formula is as follows:

[0014]

[0015] Further, the metal rhodium salt is one of rhodium(II) acetylacetonate dicarbonyl, rhodium(II) trifluoroacetate dimer, rhodium nitrate, rhodium(I) acetylacetonate carbonyltriphenylphosphine, chlorocarbonylbis(triphenylphosphine)rhodium(I), tricarbonylhydridotris(triphenylphosphine)rhodium(I), and rhodium(III) chloride. The metal rhodium salt is preferably rhodium(II) acetylacetonate dicarbonyl.

[0016] Further, the organic solvent is one of n-hexane, 1,2-dichloroethane, dichloromethane, acetonitrile, acetone, ethylene glycol dimethyl ether, tetrahydrofuran, 1,4-dioxane, ethyl acetate, and DMF. The organic solvent is preferably 1,2-dichloroethane.

[0017] Further, the separation operation is silica gel column chromatography separation method, and the specific operation is: packing the column with petroleum ether, and the eluent is petroleum ether:ethyl acetate with a volume ratio of 60:1.

[0018] Further, the reaction temperature is 20 - 110 °C, preferably 40 °C.

[0019] Acetic anhydride is used as a formic acid activator.

[0020] The reaction mechanism of the present invention is as follows: First, Rh(acac)(CO)2 complexes with the ligand and formic acid, loses one molecule of CO and Hacac to generate intermediate M1. After removing one molecule of CO2, Rh-H species M2 is generated. Then, it undergoes hydro-rhodation reaction with the standard substrate benzylidene cyclopropane to generate intermediate M3. When intermediate M3 undergoes β-C elimination, the cyclopropane ring opens to generate intermediate M4. Then, CO migrates and inserts into the C-Rh bond to form intermediate M5. Acetic anhydride and formic acid generate methyl ethyl anhydride, which undergoes oxidative addition with intermediate M5 to generate Rh-H species M6. After reduction, linear γ,δ-unsaturated aldehyde 2a and Rh complex M7 are generated. Then, the carbonyl group of complex M7 migrates to generate intermediate M8, which is then attacked by formic acid to remove the acetate ion to generate Rh complex M1 to complete the catalytic cycle. The specific reaction mechanism is as follows:

[0021]

[0022] The beneficial effects of the present invention are as follows: The present invention is reasonably designed and has a simple preparation method, with the following advantages:

[0023] (1) The present invention uses metal rhodium salt and phosphine ligand as catalysts, reacts benzylidene cyclopropane with an equivalent amount of formic acid, and can obtain the corresponding γ,δ-unsaturated aldehyde and its derivatives under very mild conditions. The present invention uses formic acid as the carbonyl source and hydrogen source, and successfully solves the problem of selective ring-opening hydroformylation reaction of benzylidene cyclopropane;

[0024] (2) The reaction conditions of the present invention are mild. Using formic acid as the carbonyl source and hydrogen source, it avoids the use of carbon monoxide and hydrogen in traditional hydroformylation reactions, avoids the generation of toxic pollutants, is easy to operate, has a good yield, can greatly save energy and improve synthesis efficiency. At the same time, the γ,δ-unsaturated aldehyde compounds obtained by the ring-opening hydroformylation reaction of benzylidene cyclopropane are analogs of many bioactive molecules and have potential biological activities. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 1H NMR spectrum of (E)-5-phenylpent-4-enal (structural formula 2a) synthesized in Example 1 1 1H NMR spectrum;

[0027] Figure 2(E)-5-phenylpent-4-enal (structural formula 2a) synthesized in Example 1 13 13C NMR spectrum;

[0028] Figure 3 (E)-5-(p-tolyl)pent-4-enal (structural formula 2b) synthesized in Example 2 1 1H NMR spectrum;

[0029] Figure 4 (E)-5-(p-tolyl)pent-4-enal (structural formula 2b) synthesized in Example 2 13 13C NMR spectrum;

[0030] Figure 5 (E)-5-(4-isobutylphenyl)pent-4-enal (structural formula 2c) synthesized in Example 3 1 1H NMR spectrum;

[0031] Figure 6 (E)-5-(4-isobutylphenyl)pent-4-enal (structural formula 2c) synthesized in Example 3 13 13C NMR spectrum;

[0032] Figure 7 (E)-5-([1,1'-biphenyl]-4-yl)pent-4-enal (structural formula 2d) synthesized in Example 4 1 1H NMR spectrum;

[0033] Figure 8 (E)-5-([1,1'-biphenyl]-4-yl)pent-4-enal (structural formula 2d) synthesized in Example 4 13 13C NMR spectrum;

[0034] Figure 9 (E)-5-(4-methoxyphenyl)pent-4-enal (structural formula 2e) synthesized in Example 5 1 1H NMR spectrum;

[0035] Figure 10 (E)-5-(4-methoxyphenyl)pent-4-enal (structural formula 2e) synthesized in Example 5 13 13C NMR spectrum;

[0036] Figure 11 (E)-5-(4-(benzyloxy)phenyl)pent-4-enal (structural formula 2f) synthesized in Example 6 1 1H NMR spectrum;

[0037] Figure 12(E)-5-(4-(Benzyloxy)phenyl)penta-4-enal (structural formula 2f) synthesized in Example 6 13 13C NMR spectrum;

[0038] Figure 13 (E)-5-(4-Fluorophenyl)penta-4-enal (structural formula 2g) synthesized in Example 7 1 1H NMR spectrum;

[0039] Figure 14 (E)-5-(4-Fluorophenyl)penta-4-enal (structural formula 2g) synthesized in Example 7 13 13C NMR spectrum;

[0040] Figure 15 (E)-5-(4-Chlorophenyl)penta-4-enal (structural formula 2h) synthesized in Example 8 1 1H NMR spectrum;

[0041] Figure 16 (E)-5-(4-Chlorophenyl)penta-4-enal (structural formula 2h) synthesized in Example 8 13 13C NMR spectrum;

[0042] Figure 17 (E)-5-(4-Bromophenyl)penta-4-enal (structural formula 2i) synthesized in Example 9 1 1H NMR spectrum;

[0043] Figure 18 (E)-5-(4-Bromophenyl)penta-4-enal (structural formula 2i) synthesized in Example 9 13 13C NMR spectrum;

[0044] Figure 19 (E)-5-(4-(Trifluoromethyl)phenyl)penta-4-enal (structural formula 2j) synthesized in Example 10 1 1H NMR spectrum;

[0045] Figure 20 (E)-5-(4-(Trifluoromethyl)phenyl)penta-4-enal (structural formula 2j) synthesized in Example 10 13 13C NMR spectrum;

[0046] Figure 21 (E)-5-(m-Tolyl)penta-4-enal (structural formula 2k) synthesized in Example 11 1 1H NMR spectrum;

[0047] Figure 22 (E)-5-(m-Tolyl)penta-4-enal (structural formula 2k) synthesized in Example 1113 13C NMR spectrum

[0048] Figure 23 13C NMR spectrum of (E)-5-(3,4-dimethylphenyl)penta-4-enal (structural formula 2m) synthesized in Example 13 1 1H NMR spectrum;

[0049] Figure 24 1H NMR spectrum of (E)-5-(3,4-dimethylphenyl)penta-4-enal (structural formula 2m) synthesized in Example 13 13 13C NMR spectrum

[0050] Figure 25 1H NMR spectrum of (E)-5-(4-fluoro-3-methylphenyl)penta-4-enal (structural formula 2n) synthesized in Example 14 1 1H NMR spectrum;

[0051] Figure 26 1H NMR spectrum of (E)-5-(4-fluoro-3-methylphenyl)penta-4-enal (structural formula 2n) synthesized in Example 14 13 13C NMR spectrum

[0052] Figure 27 1H NMR spectrum of (E)-5-(naphthalen-1-yl)penta-4-enal (structural formula 2o) synthesized in Example 15 1 1H NMR spectrum;

[0053] Figure 28 1H NMR spectrum of (E)-5-(naphthalen-1-yl)penta-4-enal (structural formula 2o) synthesized in Example 15 13 13C NMR spectrum

[0054] Figure 29 1H NMR spectrum of (E)-5-(benzo[d][1,3]dioxol-5-yl)penta-4-enal (structural formula 2g) synthesized in Example 16 1 1H NMR spectrum;

[0055] Figure 30 1H NMR spectrum of (E)-5-(benzo[d][1,3]dioxol-5-yl)penta-4-enal (structural formula 2g) synthesized in Example 16 13 13C NMR spectrum

[0056] Figure 31 1H NMR spectrum of (E)-5-(thiophen-3-yl)penta-4-enal (structural formula 2q) synthesized in Example 17 1 1H NMR spectrum;

[0057] Figure 32 1H NMR spectrum of (E)-5-(thiophen-3-yl)penta-4-enal (structural formula 2q) synthesized in Example 1713 13C NMR spectrum Detailed implementation manners

[0058] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs.

[0059] It should be noted that the terms used herein are only for describing the specific implementation manners and are not intended to limit the exemplary implementation manners according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms also include the plural forms. In addition, it should also be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0060] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0061] Example 1 (E)-5-phenylpent-4-enal (see Structural formula 2a)

[0062] The synthesis reaction of (E)-5-phenylpent-4-enal 2a is as follows:

[0063]

[0064] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1a (0.065 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to the reactor and mixed thoroughly. After sealing, the temperature of the mixed system in the reactor was raised to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The target product (0.0557 g, yield 70%) was obtained by column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1), which was a yellow oil.

[0065] The results of product structure confirmation are as follows: 11H NMR (400 MHz, CDCl3) δ 9.83 (t, J = 1.2 Hz, 1H), 7.37 - 7.7.27 (m, 4H), 7.24 - 7.18 (m, 1H), 6.43 (d, J = 15.6 Hz, 1H), 6.21 (dt, J = 16.0, 6.8 Hz, 1H), 2.67 - 2.61 (m, 2H), 2.59 - 2.52 (m, 2H); 13 13C NMR (100 MHz, CDCl3) δ 202.0, 137.4, 131.3, 128.7, 128.3, 127.4, 126.2, 43.5, 25.7.

[0066] The synthesized compound was identified as the target compound (E)-5-phenylpent-4-enal 2a by structure determination.

[0067] Example 2 (E)-5-(p-tolyl)pent-4-enal (see structural formula 2b)

[0068] (E)-5-(p-tolyl)pent-4-enal 2b was synthesized as follows:

[0069]

[0070] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1b (0.0722 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol), and formic acid (0.0690 g, 1.50 mmol) were successively added to the reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The target product (0.0593 g, yield 68%) was obtained as a pale yellow oil by column chromatography separation (packed with petroleum ether, eluent: petroleum ether:ethyl acetate volume ratio 60:1).

[0071] The results of product structure confirmation are as follows: 1 1H NMR (400 MHz, CDCl3) δ 9.82 (br s, 1H), 7.23 (d, J = 8.0 Hz, 2H), 7.11 (d, J = 7.6 Hz, 2H), 6.40 (d, J = 15.6 Hz, 1H), 6.15 (dt, J = 16.0, 6.8 Hz, 1H), 2.68 - 2.59 (m, 2H), 2.58 - 2.50 (m, 2H), 2.33 (s, 3H); 1313C NMR (100 MHz, CDCl3) δ 202.1, 137.2, 134.6, 131.1, 129.4, 127.3, 126.1, 43.6, 25.7, 21.4。

[0072] The synthesized compound was identified by its structure as the target compound (E)-5-(p-tolyl)pent-4-enal 2b.

[0073] Example 3 (E)-5-(4-isobutylphenyl)pent-4-enal (see Structural Formula 2c)

[0074] The synthesis reaction of (E)-5-(4-isobutylphenyl)pent-4-enal 2c is as follows:

[0075]

[0076] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1c (0.0931 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The target product (0.0574 g, yield 53%) was obtained as a yellow oil by column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0077] The results of product structure confirmation are as follows: 1 1H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.24 (d, J = 8.0 Hz, 2H), 7.07 (d, J = 8.0 Hz, 2H), 6.41 (d, J = 16.0 Hz, 1H), 6.16 (dt, J = 15.6, 6.4 Hz, 1H), 2.66 - 2.59 (m, 2H), 2.58 - 2.50 (m, 2H), 2.44 (d, J = 7.2 Hz, 2H), 1.90 - 1.77 (m, 1H), 0.89 (d, J = 6.8 Hz, 6H); 13 13C NMR (100 MHz, CDCl3) δ 202.2, 141.1, 134.8, 131.2, 129.5, 127.3, 126.0, 45.3, 43.6, 30.4, 25.8, 22.6. HRMS(ESI) calcd for C 15 H20 ONa(M+Na) + : 239.1406; found: 239.1408.

[0078] The synthesized compound was identified by its structure as the target compound (E)-5-(4-isobutylphenyl)pent-4-enal 2c.

[0079] Example 4 (E)-5-([1,1'-biphenyl]-4-yl)pent-4-enal (see Structural Formula 2d)

[0080] (E)-5-([1,1'-biphenyl]-4-yl)pent-4-enal 2d was synthesized as follows:

[0081]

[0082] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1d (0.1031 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol), and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped, and after natural cooling to room temperature (25 °C, the same below), column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1) was used to obtain a white solid, which was the target product (0.0898 g, yield 76%).

[0083] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.84 (t, J = 1.2 Hz, 1H), 7.61 (d, J = 7.2 Hz, 2H), 7.56 (d, J = 8.0 Hz, 2H), 7.49 - 739 (m, 4H), 7.35 (t, J = 7.2 Hz, 1H), 6.48 (d, J = 16.0 Hz, 1H), 6.26 (dt, J = 16.0, 6.8 Hz, 1H), 2.75 - 2.63 (m, 2H), 2.62 - 2.54 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.0, 140.9, 140.2, 136.4, 130.9, 129.0, 128.5, 127.43, 127.41, 127.1, 126.6, 43.5, 25.8.

[0084] The synthesized compound was identified structurally as the target compound (E)-5-([1,1'-biphenyl]-4-yl)pent-4-enal 2d.

[0085] Example 5 (E)-5-(4-methoxyphenyl)pent-4-enal (see structural formula 2e)

[0086] The synthesis reaction of (E)-5-(4-methoxyphenyl)pent-4-enal 2e is as follows:

[0087]

[0088] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1e (0.0801 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to the reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was allowed to cool naturally to room temperature (25 °C, the same below). The target product (0.0653 g, yield 69%) was obtained by column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1), which was a yellow oil.

[0089] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.30 - 7.24 (m, 2H), 6.86 - 6.81 (m, 2H), 6.37 (d, J = 15.6 Hz, 1H), 6.06 (dt, J = 15.6, 6.8 Hz, 1H), 3.80 (s, 3H), 2.65 - 2.58 (m, 2H), 2.56 - 2.49 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.2, 159.1, 130.7, 130.2, 127.3, 126.1, 114.1, 55.5, 43.7, 25.7.

[0090] The synthesized compound was identified structurally as the target compound (E)-5-(4-methoxyphenyl)pent-4-enal 2e.

[0091] Example 6 (E)-5-(4-(benzyloxy)phenyl)pent-4-enal (see structural formula 2f)

[0092] The synthesis reaction of (E)-5-(4-(benzyloxy)phenyl)pent-4-enal 2f is as follows:

[0093]

[0094] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1f (0.1182 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped, and after natural cooling to room temperature (25 °C, the same below), column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1) was used to separate and obtain a white solid, which was the target product (0.0799 g, yield 60%).

[0095] The results of the confirmation of the product structure are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.46 - 7.45 (m, 2H), 7.41 - 7.35 (m, 2H), 7.35 - 7.29 (m, 1H), 7.28 - 7.24 (m, 2H), 6.94 - 6.88 (m, 2H), 6.37 (d, J = 15.6 Hz, 1H), 6.06 (dt, J = 16.0, 6.8 Hz, 1H), 5.06 (s, 2H), 2.65 - 2.58 (m, 2H), 2.57 - 2.49 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.2, 158.3, 137.2, 130.7, 130.5, 128.8, 128.2, 127.7, 127.4, 126.3, 115.1, 70.2, 43.7, 25.7. HRMS (ESI) calcd for C 18 H 18 O2Na (M + Na) + : 289.1199; found: 289.1199.

[0096] The compound synthesized through structure identification was the target compound (E)-5-(4-(benzyloxy)phenyl)penta-4-enal 2f.

[0097] Example 7 (E)-5-(4-fluorophenyl)penta-4-enal (see structural formula 2g)

[0098] The synthesis reaction of (E)-5-(4-fluorophenyl)penta-4-enal 2g is as follows:

[0099]

[0100] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1 g (0.0741 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to the reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The pale yellow oil was separated by column chromatography (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1), and the target product (0.0650 g, yield 73%) was obtained.

[0101] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (br s, 1H), 7.36 - 7.24 (m, 2H), 6.98 (t, J = 8.8 Hz, 2H), 6.39 (d, J = 16.0 Hz, 1H), 6.11 (dt, J = 16.0, 6.8 Hz, 1H), 2.63 (t, J = 6.8 Hz, 2H), 2.58 - 2.49 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 201.9, 162.3 (d, J = 244.6 Hz), 133.5 (d, J = 3.4 Hz), 130.1, 128.1 (d, J = 2.4 Hz), 127.7 (d, J = 7.9 Hz), 115.6 (d, J = 21.5 Hz), 43.5, 25.6. HRMS (ESI) calcd for C 11 H 11 FONa (M+Na) + : 201.0686; found: 201.0687.

[0102] The synthesized compound was identified as the target compound (E)-5-(4-fluorophenyl)penta-4-enal 2g by structure determination.

[0103] Example 8 (E)-5-(4-chlorophenyl)penta-4-enal (see structural formula 2h)

[0104] (E)-5-(4-chlorophenyl)penta-4-enal 2h was synthesized as follows:

[0105]

[0106] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1h (0.0823 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The target product (0.0794 g, yield 82%) was obtained by column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1), which was a pale yellow oil.

[0107] The results of product structure confirmation are as follows: 1 1H NMR (400 MHz, CDCl3) δ 9.83 (t, J = 1.6 Hz, 1H), 7.28 - 7.24 (m, 4H), 6.39 (d, J = 16.0 Hz, 1H), 6.19 (dt, J = 16.0, 6.8 Hz, 1H), 2.68 - 2.60 (m, 2H), 2.59 - 2.51 (m, 2H); 13 13C NMR (100 MHz, CDCl3) δ 201.8, 135.9, 133.0, 130.2, 129.1, 128.9, 127.4, 43.4, 25.6.

[0108] The synthesized compound was identified by structure as the target compound (E)-5-(4-chlorophenyl)pent-4-enal 2h.

[0109] Example 9 (E)-5-(4-bromophenyl)pent-4-enal (see Structural Formula 2i)

[0110] The synthesis reaction of (E)-5-(4-bromophenyl)pent-4-enal 2i is as follows:

[0111]

[0112] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1i (0.1045 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to the reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The target product (0.0895 g, yield 75%) was obtained by column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1), which was a pale yellow oil.

[0113] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.41 (d, J = 8.4 Hz, 2H), 7.19 (d, J = 8.4 Hz, 2H), 6.36 (d, J = 16.0 Hz, 1H), 6.19 (dt, J = 15.6, 6.8 Hz, 1H), 2.68 - 2.60 (m, 2H), 2.58 - 2.49 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 201.8, 136.3, 131.8, 130.2, 129.2, 127.8, 121.1, 43.4, 25.7.

[0114] The compound synthesized by structure identification was the target compound (E)-5-(4-bromophenyl)pent-4-enal 2i.

[0115] Example 10 (E)-5-(4-(trifluoromethyl)phenyl)pent-4-enal (see structural formula 2j)

[0116] The synthesis reaction of (E)-5-(4-(trifluoromethyl)phenyl)pent-4-enal 2j is as follows:

[0117]

[0118] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1j (0.0991 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was allowed to cool naturally to room temperature (25 °C, the same below). The yellow oil, namely the target product (0.0696 g, yield 61%), was obtained by column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0119] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.84 (t, J = 1.6 Hz, 1H), 7.54 (d, J = 8.0 Hz, 2H), 7.42 (d, J = 8.0 Hz, 2H), 6.46 (d, J = 15.6, 1H), 6.31 (dt, J = 16.0, 6.4 Hz, 1H), 2.70 - 2.63 (m, 2H), 2.62 - 2.54 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 201.6, 140.9, 131.2, 130.2, 129.3 (q, J = 32.2 Hz), 126.4, 125.7 (q, J = 4.1 Hz), 124.4 (q, J = 270.2 Hz), 43.3, 25.7。

[0120] The compound synthesized was identified as the target compound (E)-5-(4-(trifluoromethyl)phenyl)penta-4-enal 2j by structure identification.

[0121] Example 11 (E)-5-(m-tolyl)penta-4-enal (see structural formula 2k)

[0122] (E)-5-(m-tolyl)penta-4-enal 2k was synthesized as follows:

[0123]

[0124] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1k (0.0722 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped, and after natural cooling to room temperature (25 °C, the same below), column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1) was used to obtain a pale yellow oil, which was the target product (0.0383 g, yield 44%).

[0125] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.83 (t, J = 1.6 Hz, 1H), 7.19 (t, J = 7.6 Hz, 1H), 7.16 (s, 1H), 7.14 (d, J = 7.6 Hz, 1H), 7.04 (d, J = 7.2 Hz, 1H), 6.41 (d, J = 15.6 Hz, 1H), 6.19 (dt, J = 15.6, 6.8 Hz, 1H), 2.68 - 2.60 (m, 2H), 2.59 - 2.51 (m, 2H), 2.34 (s, 3H); 13 C NMR (100 MHz, CDCl3) δ 202.1, 138.3, 137.3, 131.4, 128.6, 128.2, 128.1, 126.9, 123.4, 43.6, 25.7, 21.6; HRMS (ESI) calcd for C 12 H 14 ONa (M + Na) + : 197.0937; found: 197.0938.

[0126] The synthesized compound was identified by structure as the target compound (E)-5-(m-tolyl)pent-4-enal 2k.

[0127] Example 12 (E)-5-(o-tolyl)pent-4-enal (see structural formula 2l)

[0128] The synthesis reaction of (E)-5-(o-tolyl)pent-4-enal 2l is as follows:

[0129]

[0130] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1l (0.0722 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol), and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The target product (0.0503 g, yield 58%) was obtained as a pale yellow oil by column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0131] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.84 (t, J = 1.6 Hz, 1H), 7.44 - 7.35 (m, 1H), 7.19 - 7.10 (m, 3H), 6.66 (d, J = 15.6 Hz, 1H), 6.07 (dt, J = 15.6, 6.8 Hz, 1H), 2.69 - 2.62 (m, 2H), 2.62 - 2.54 (m, 2H), 2.33 (s, 3H); 13 C NMR (100 MHz, CDCl3) δ 202.1, 136.5, 135.3, 130.4, 129.7, 129.2, 127.4, 126.3, 125.7, 43.6, 26.0, 20.0; HRMS (ESI) calcd for C 12 H 14 ONa (M + Na) + : 197.0937; found: 197.0939.

[0132] The synthesized compound was identified as the target compound (E)-5-(o-tolyl)pent-4-enal 2l by structure determination.

[0133] Example 13 (E)-5-(3,4-Dimethylphenyl)pent-4-enal (see structural formula 2m)

[0134] (E)-5-(3,4-Dimethylphenyl)pent-4-enal 2m was synthesized as follows:

[0135]

[0136] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1m (0.0791 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The yellow oil, i.e., the target product (0.0632 g, yield 67%), was obtained by column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0137] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.12 (s, 1H), 7.09 - 7.03 (m, 2H), 6.38 (d, J = 16.0 Hz, 1H), 6.14 (dt, J = 16.0, 6.8 Hz, 1H), 2.65 - 2.59 (m, 2H), 2.57 - 2.50 (m, 2H), 2.25 (s, 3H), 2.24 (s, 3H); 13 C NMR (100 MHz, CDCl3) δ 202.2, 136.8, 135.9, 135.0, 131.2, 130.0, 127.5, 127.1, 123.7, 43.6, 25.8, 20.0, 19.7. HRMS (ESI) calcd for C 13 H 16 ONa (M+Na) + : 211.1093; found: 211.1095.

[0138] The synthesized compound was identified as the target compound (E)-5-(3,4-dimethylphenyl)penta-4-enal 2m by structure identification.

[0139] Example 14 (E)-5-(4-Fluoro-3-methylphenyl)penta-4-enal (see structural formula 2n)

[0140] The synthesis reaction of (E)-5-(4-fluoro-3-methylphenyl)penta-4-enal 2n is as follows:

[0141]

[0142] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1n (0.0811 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol), and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was allowed to cool naturally to room temperature (25 °C, the same below). The yellow oil, which is the target product (0.0732 g, yield 76%), was obtained by column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0143] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.18 - 7.06 (m, 2H), 6.92 (t, J = 9.2 Hz, 1H), 6.35 (d, J = 15.6 Hz, 1H), 6.09 (dt, J = 16.0, 6.8 Hz, 1H), 2.68 - 2.59 (m, 2H), 2.57 - 2.49 (m, 2H), 2.25 (d, J = 4.0 Hz, 3H); 13 C NMR (100 MHz, CDCl3) δ 202.0, 160.9 (d, J = 243.7 Hz), 133.2 (d, J = 2.6 Hz), 130.3, 129.2 (d, J = 5.0 Hz), 127.7 (d, J = 2.3 Hz), 125.1 (d, J = 7.8 Hz), 125.0 (d, J = 17.5 Hz), 115.2 (d, J = 22.4 Hz), 43.6, 25.7, 14.8 (d, J = 2.6 Hz). HRMS (ESI) calcd for C 12 H 13 FONa (M+Na) + : 215.0843; found: 215.0846.

[0144] The synthesized compound was identified as the target compound (E)-5-(4-fluoro-3-methylphenyl)penta-4-enal 2n by structure determination.

[0145] Example 15 (E)-5-(naphthalen-1-yl)penta-4-enal (see Structural Formula 20)

[0146] (E)-5-(naphthalen-1-yl)penta-4-enal 20 was synthesized as follows:

[0147]

[0148] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1o (0.0901 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to a reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The yellow oil, namely the target product (0.0635 g, yield 60%), was obtained by column chromatography separation (using petroleum ether to fill the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0149] The results of the product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.88 (t, J = 1.6 Hz, 1H), 8.08 (d, J = 8.0 Hz, 1H), 7.88 - 7.81 (m, 1H), 7.76 (d, J = 8.4 Hz, 1H), 7.57 - 7.46 (m, 3H), 7.43 (t, J = 7.6 Hz, 1H), 7.18 (d, J = 15.2 Hz, 1H), 6.22 (dt, J = 15.6, 6.4 Hz, 1H), 2.79 - 2.63 (m, 4H); 13 C NMR (100 MHz, CDCl3) δ 201.9, 135.2, 133.8, 131.7, 131.3, 128.71, 128.68, 127.9, 126.2, 125.9, 125.8, 124.0, 123.9, 43.6, 26.1. HRMS (ESI) calcd for C 15 H 14 ONa (M+Na) + : 233.0937; found: 233.0938.

[0150] The compound synthesized through structure identification is the target compound (E)-5-(naphthalen-1-yl)pent-4-enal 20.

[0151] Example 16 (E)-5-(benzo[d][1,3]dioxol-5-yl)pent-4-enal (see structural formula 2p)

[0152] The synthesis reaction of (E)-5-(benzo[d][1,3]dioxol-5-yl)pent-4-enal 2p is as follows:

[0153]

[0154] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1p (0.0871 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added to the reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The yellow oil, namely the target product (0.0623 g, yield 61%), was obtained by column chromatography separation (packed with petroleum ether, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0155] The results of the product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 6.88 (s, 1H), 6.81 - 6.70 (m, 2H), 6.34 (d, J = 16.0 Hz, 1H), 6.02 (dt, J = 15.6, 6.8 Hz, 1H), 5.94 (s, 2H), 2.68 - 2.56 (m, 2H), 2.56 - 2.46 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.0, 148.2, 147.1, 131.9, 130.9, 126.6, 120.7, 108.5, 105.6, 101.2, 43.6, 25.6; HRMS (ESI) calcd for C 12 H 12 O3Na (M+Na) + : 227.0679; found: 227.0680.

[0156] The synthesized compound was identified by structure as the target compound (E)-5-(benzo[d][1,3]dioxol-5-yl)penta-4-enal 2p.

[0157] Example 17 (E)-5-(thiophen-3-yl)penta-4-enal (see structural formula 2q)

[0158] (E)-5-(thiophen-3-yl)penta-4-enal 2q was synthesized as follows:

[0159]

[0160] Under argon protection, Rh(acac)(CO)2 (0.0026 g, 0.010 mmol), triphenylphosphine (0.0105 g, 0.040 mmol), 0.5 mL of 1,2-dichloroethane, 1q (0.0681 g, 0.5 mmol), acetic anhydride (0.1531 g, 1.50 mmol) and formic acid (0.0690 g, 1.50 mmol) were successively added into the reactor and mixed thoroughly. After sealing, the mixed system in the reactor was heated to 40 °C by a heating plate and reacted for 36 hours. Then, the heating was stopped and it was naturally cooled to room temperature (25 °C, the same below). The yellow oil, namely the target product (0.0570 g, yield 69%), was obtained by column chromatography separation (using petroleum ether to pack the column, and the eluent was petroleum ether:ethyl acetate volume ratio 60:1).

[0161] The results of product structure confirmation are as follows: 1 H NMR (400 MHz, CDCl3) δ 9.82 (t, J = 1.6 Hz, 1H), 7.26 - 7.23 (m 1H), 7.17 (d, J = 4.4 Hz, 1H), 7.11 - 7.03 (m, 1H), 6.44 (d, J = 16.0 Hz, 1H), 6.06 (dt, J = 15.6, 6.8 Hz, 1H), 2.65 - 2.58 (m, 2H), 2.56 - 2.47 (m, 2H); 13 C NMR (100 MHz, CDCl3) δ 202.0, 140.0, 128.3, 126.2, 125.6, 125.0, 121.4, 43.6, 25.6; HRMS (ESI) calcd for C9H 10 OSNa (M+Na) + : 189.0345; found: 189.0344.

[0162] The synthesized compound was identified as the target compound (E)-5-(thiophen-3-yl)penta-4-enal 2q by structure identification.

[0163] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing examples, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing examples, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source, characterized in that: Under a nitrogen protective atmosphere, benzalcyclopropane, formic acid, metal rhodium salt, phosphine ligand and acetic anhydride are dispersed in an organic solvent and reacted to obtain a preliminary product of γ,δ unsaturated aldehyde; after the reaction is completed, the preliminary product of γ,δ unsaturated aldehyde is separated to obtain the target product γ,δ unsaturated aldehyde.

2. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The structural formula of the benzylidenecyclopropane is Wherein, R is one of alkyl, phenyl, fluorine, chlorine, bromine, trifluoromethyl, naphthalene and thiophene.

3. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The molar ratio of the benzylidene cyclopropane, formic acid, metal rhodium salt, phosphine ligand and acetic anhydride is 1:(1-4):(0.001-0.05):(0.004-0.2):(1-4).

4. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The phosphine ligand is one of PPh3, (o-OMe-Ph)3P, (pF-Ph)3P, (2-thienyl)3P, (2-furyl)3P, PPh2Cy, PPhCy2, PCy3, (C6F5)3P, dppm, dppb, and dppf.

5. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The metal rhodium salt is one of dicarbonyl acetylacetonate rhodium, trifluoroacetate rhodium (II) dimer, rhodium nitrate, acetylacetonate carbonyl triphenylphosphine rhodium, chloride carbonyl bistriphenylphosphine rhodium, tri(triphenylphosphine) carbonyl rhodium hydride, and rhodium trichloride.

6. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The organic solvent is one of n-hexane, 1,2-dichloroethane, dichloromethane, acetonitrile, acetone, ethylene glycol dimethyl ether, tetrahydrofuran, 1,4-dioxane, ethyl acetate and DMF.

7. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The separation operation is silica gel column chromatography separation method.

8. The ring-opening hydroformylation reaction of benzylidenecyclopropane using formic acid as a carbonyl source according to claim 1, characterized in that: The reaction temperature is 20-110°C.

Images