Synthesis method of sulfite compound

Abstract

The invention discloses a synthesis method of a sulfite compound, which comprises the following steps: by taking an alcohol compound as a raw material, sulfur hexafluoride as a sulfinylation reagent and an organic solvent as a reaction solvent, carrying out illumination reaction in the presence of a photocatalyst and alkali to obtain the sulfite compound, the alcohol compound is monohydric alcohol or dihydric alcohol; when the monohydric alcohol is secondary alcohol, a benzoic acid compound is added as an additive. The invention discloses a synthesis method of a novel sulfite compound, which comprises the following steps: in the presence of a photocatalyst and alkali, reducing SF6 by utilizing an illumination condition, and reacting an SF6 decomposition product with alcohol to form a sulfite product; according to the method, the greenhouse gas SF6 is effectively activated and utilized, the SF6 is turned into wealth, the required raw materials are simple and easy to obtain, the reaction conditions are simple and convenient, the method is green and energy-saving, and the method has high application value.

Description

Technical Field

[0001] The invention relates to the technical field of organic intermediate synthesis, and in particular to a method for synthesizing sulfite compounds. Background Art

[0002] Sulfite compounds are an important class of chemicals. Sulfite acaricides such as Propargite have the characteristics of high efficiency, low toxicity, broad spectrum, long duration, harmlessness to natural enemies, and low resistance to drugs. Since its launch in 1964, it has been widely used in various agricultural and forestry mites. Among them, studies have confirmed that the sulfite structure plays an important role in maintaining the acaricidal activity of Propargite. Sulfites are currently also used as lithium-ion battery electrolyte additives: such as ethylene sulfite (ES), diethyl sulfite (DES), etc., which are used in lithium-ion battery electrolytes to broaden the temperature compatibility and electrochemical window, help improve battery performance, and improve the battery's cycle stability and safety. At present, the methods for the sulfenylation of primary alcohols are:

[0003] Method 1: Using dichloromethane as solvent and using a dichlorothionyl / sodium sulfite system, at room temperature, react with alcohol compounds to prepare sulfite compounds.

[0004]

[0005] This method has mild conditions and uses cheap and readily available SOCl2, but SOCl2 is highly toxic and corrosive, and produces SO2 gas, which is harmful to the environment.

[0006] Method 2: Use N-sulfinylfluoroalkanesulfonylamine and alcohol to prepare sulfite compounds. Because of the presence of polar nitrogen-sulfur double bonds and electron-withdrawing groups, the reaction is favorable to obtain the corresponding sulfite compounds.

[0007]

[0008] This method is highly efficient and can obtain the corresponding product in a relatively short time. However, the raw material N-sulfinylfluoroalkanesulfonylamine used is expensive, the synthesis is cumbersome, and it is difficult to obtain.

[0009] In summary, there are relatively few methods for synthesizing sulfite compounds. Therefore, there is still a need to develop a method for synthesizing sulfite compounds that is simple to operate, has a high reaction yield, and is easy to promote in industrial production.

[0010] SF6 gas is a colorless, odorless, non-toxic, non-combustible, non-corrosive gas at room temperature and pressure. It is an inert gas with high stability. It does not decompose at high temperatures of 500-600°C and does not react with acids, alkalis, water, etc. It is also an insulating gas with excellent insulation properties and can be used to extinguish high-voltage arcs. Therefore, it is widely used in the power industry. However, SF6 has a strong greenhouse effect, and its climate warming power is 23,900 times that of CO2. Secondly, because SF6 is an artificially synthesized gas with quite stable chemical properties, SF6 is extremely difficult to decompose and its natural lifespan in the atmosphere can be as long as more than 3,000 years. As it continues to accumulate in the atmosphere, the greenhouse effect it brings is also continuously increasing. The emission of SF6 is restricted, and the power industry faces difficulties in handling large amounts of SF6.

[0011] SF6 itself has a high potential for utilization. One SF6 molecule contains one sulfur atom and six fluorine atoms, so it is a rich source of fluorine and sulfur. Therefore, in order to alleviate the environmental pressure brought by SF6, activating SF6 to utilize its decomposition products and applying them in the field of organic synthesis is a good solution. Summary of the invention

[0012] The technical problem to be solved by the present invention is how to synthesize sulfite compounds in a simple, safe, green and energy-saving manner.

[0013] The present invention solves the above technical problems through the following technical means:

[0014] A method for synthesizing a sulfite compound, which uses an alcohol compound as a raw material, sulfur hexafluoride as a sulfenylating agent, and an organic solvent as a reaction solvent, and performs a light irradiation reaction in the presence of a photocatalyst and a base to obtain the sulfite compound;

[0015] Wherein, the alcohol compound is a monohydric alcohol or a dihydric alcohol; when the monohydric alcohol is a dihydric alcohol, a benzoic acid compound is added as an additive.

[0016] In the present invention, in the presence of a photocatalyst and a base, an alcohol compound and SF6 react to form a sulfite compound; the reaction formula is as follows:

[0017]

[0018] Preferably, the structural formula of the monohydric alcohol is R-OH, wherein R is selected from a C2-C7 pure alkyl group, a C3-C6 cycloalkyl group, a C2-C5 alkyl group containing an alkenyl or alkynyl group, a C2-C5 alkyl group containing an aromatic group, 20 The alkyl group The aromatic group is one of a Br-substituted benzene ring, a five-membered heterocyclic ring containing an S atom, a rigid naphthalene ring, and a benzene ring.

[0019] Preferably, the monohydric alcohol is one of phenylethanol, 2-(4-bromophenyl)ethane-1-ol, 2-(thiophen-2-yl)ethane-1-ol, 2-(naphthalene-1-yl)ethane-1-ol, cyclohexylmethanol, pent-4-en-1-ol, pent-4-yn-1-ol, ethanol, and cyclohexanol.

[0020] Preferably, the diol is 1-phenylethane-1,2-diol or 1,2-benzenedimethanol.

[0021] Preferably, the organic solvent is a mixture of one or more of tetrahydrofuran, acetonitrile or dichloromethane.

[0022] Preferably, the organic solvent is tetrahydrofuran.

[0023] The present invention is carried out in a system with a single organic solvent; if necessary, other organic solvents may also be present in the system, but from the perspective of reaction yield and simplicity of operation, it is preferred not to add other organic solvents, that is, to use a single organic solvent as the reaction solvent.

[0024] Preferably, the photocatalyst is an organic photocatalyst or a mixture of one or more transition metal photocatalysts.

[0025] Preferably, the photocatalyst is 4CZIPN, Mes-Acr + A mixture of one or more of ClO4ˉ, Ir[dF(CF3)ppy]2(dtbbpy)PF6, and Ir(dtbbpy)ppy2PF6.

[0026] Preferably, the organic photocatalyst is 4CZIPN.

[0027] Preferably, the transition metal photocatalyst is Ir[dF(CF3)ppy]2(dtbbpy)PF6.

[0028] Preferably, the base is a tertiary amine organic base.

[0029] Preferably, the base is N,N-diisopropylethylamine.

[0030] When the tertiary amine N,N-diisopropylethylamine is selected, the yield of the product sulfite is the highest.

[0031] Preferably, during the light irradiation reaction, blue light of 450 to 480 nm is used as the light source.

[0032] Preferably, the reaction temperature is 0-50° C., the reaction time is 5-48 hours, and the sulfur hexafluoride gas pressure is 1-3 atm.

[0033] Preferably, during the light irradiation reaction, the reaction temperature is room temperature.

[0034] When the temperature is room temperature and the reaction time is 15 to 28 hours, the yield of the product sulfite is the highest. The reaction temperature and reaction time of the present invention can be determined by technicians according to different alcohol compounds and actual needs.

[0035] Preferably, during the light irradiation reaction process, the time is 20 hours.

[0036] Preferably, during the light irradiation reaction, the wavelength is 465 nm; the yield of the product sulfite is highest at 465 nm.

[0037] Preferably, during the light irradiation reaction, the pressure of sulfur hexafluoride gas is 1 atm.

[0038] Preferably, the molar ratio of the base to the alcohol compound is 2:1 to 5:1; and the molar ratio of the photocatalyst to the alcohol compound is 0.010:1 to 0.002:1.

[0039] Preferably, the molar ratio of the base to the alcohol compound is 5:1.

[0040] The yield of sulfite product is highest when the molar ratio of base to alcohol compound is 5:1.

[0041] When the molar ratio of the photocatalyst to the alcohol compound is 0.005:1, the balance between the yield and cost of the sulfite product is optimal.

[0042] Preferably, the molar ratio of the photocatalyst to the alcohol compound is 0.005:1.

[0043] Preferably, the alcohol compound and the organic solvent are used in a ratio of 0.25-0.10 mmol:1 mL.

[0044] Preferably, the usage ratio of the alcohol compound to the organic solvent is 0.17 mmol:1 mL.

[0045] When the dosage ratio of alcohol compound to organic solvent is 0.17mmol:1mL, the yield of sulfite product is the highest.

[0046] Preferably, after the reaction is completed, the organic solvent is removed under vacuum, and the pure sulfite compound is obtained by separation by silica gel column chromatography (volume ratio of petroleum ether:ethyl acetate=20:1).

[0047] The advantages of the present invention are:

[0048] The present invention uses easily available alcohol compounds as reaction substrates, commercially available photocatalysts as photocatalysts, and cheap and easily available N,N-diisopropylethylamine as a base to simply and efficiently synthesize sulfite compounds under SF6 gas. Compared with other methods for synthesizing sulfite compounds, the present invention has mild reaction conditions, the reaction raw materials used (including alcohol compounds and N,N-diisopropylethylamine) are cheap and easily available, and it has the characteristics of cost saving, environmental friendliness, and industrial promotion. The intermediate produced by the decomposition of SF6 can be used as a sulfenylation agent. The method effectively activates and utilizes SF6, a greenhouse gas, and fully utilizes the decomposition products of SF6 to realize the sulfenylation of alcohols to synthesize sulfite compounds, turning SF6 into treasure.

[0049] The invention discloses a method for synthesizing sulfite compounds with a wide application range. The method is applicable to synthesizing various sulfite compounds, and the reaction has good compatibility. The invention is also applicable to diol compounds, and further, sulfite compounds can be obtained by intramolecular cyclization.

[0050] The invention can be widely applied to drug synthesis and total synthesis of natural products in industry and academia, and has high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is the H NMR spectrum of diphenylethyl sulfite described in Example 1 of the present invention;

[0052] Figure 2 This is the NMR carbon spectrum of diphenyl ethyl sulfite described in Example 1 of the present invention;

[0053] Figure 3 This is the H NMR spectrum of bis(4-bromophenethyl)sulfite described in Example 2 of the present invention;

[0054] Figure 4 This is the NMR carbon spectrum of bis(4-bromophenethyl)sulfite described in Example 2 of the present invention;

[0055] Figure 5 This is the H NMR spectrum of bis(2-(thiophen-2-yl)ethyl)sulfite described in Example 3 of the present invention;

[0056] Figure 6 This is the NMR carbon spectrum of bis(2-(thiophen-2-yl)ethyl)sulfite described in Example 3 of the present invention;

[0057] Figure 7 This is the H NMR spectrum of bis(2-(naphthalen-1-yl)ethyl)sulfite described in Example 4 of the present invention;

[0058] Figure 8The carbon NMR spectrum of bis(2-(naphthalen-1-yl)ethyl)sulfite described in Example 4 of the present invention;

[0059] Fig. 9 This is the H NMR spectrum of bis(cyclohexylmethyl)sulfite described in Example 5 of the present invention;

[0060] Fig.10 This is the NMR carbon spectrum of bis(cyclohexylmethyl)sulfite described in Example 5 of the present invention;

[0061] Fig.11 This is the H NMR spectrum of di(pent-4-en-1-yl)sulfite described in Example 6 of the present invention;

[0062] Fig.12 This is the NMR carbon spectrum of di(pent-4-en-1-yl)sulfite described in Example 6 of the present invention;

[0063] Fig.13 This is the H NMR spectrum of di(pent-4-yn-1-yl)sulfite described in Example 7 of the present invention;

[0064] Fig.14 This is the NMR carbon spectrum of di(pent-4-yn-1-yl)sulfite described in Example 7 of the present invention;

[0065] Fig.15 This is the H NMR spectrum of diethyl sulfite described in Example 8 of the present invention;

[0066] Fig.16 This is the NMR carbon spectrum of diethyl sulfite described in Example 8 of the present invention;

[0067] Fig.17 is the H NMR spectrum of 4-phenyl-1,3,2-dioxasulfane-2-oxide described in Example 9 of the present invention;

[0068] Fig.18 The carbon NMR spectrum of 4-phenyl-1,3,2-dioxasulfane-2-oxide described in Example 9 of the present invention;

[0069] Fig.19 The H NMR spectrum of 1,5-dihydrobenzo[e][1,3,2]dioxythiophene-3-oxide described in Example 10 of the present invention;

[0070] Fig. 20 This is the carbon NMR spectrum of 1,5-dihydrobenzo[e][1,3,2]dioxythiophene-3-oxide described in Example 10 of the present invention.

[0071] Fig.21 is the H NMR spectrum of dicyclohexyl sulfite described in Example 11 of the present invention;

[0072] Fig. 22 This is the carbon NMR spectrum of dicyclohexyl sulfite described in Example 11 of the present invention. DETAILED DESCRIPTION

[0073] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0074] Unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial sources.

[0075] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0076] 1 H NMR and 13 C NMR was measured using a Bruker Avance 400 spectrometer. The test temperature was room temperature, the solvent was deuterated chloroform, and the reference was selected: 1 H NMR: CHCl3 7.260 ppm; 13 C NMR: CHCl3: 77.000 ppm.

[0077] Example 1

[0078] Synthesis of Diphenyl Ethyl Sulfite

[0079] Phenylethanol (61.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and a SF6 balloon was inserted after vacuuming, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15 W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 27.1 mg of diphenylethyl sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 56%.

[0080] The NMR spectrum of the product diphenyl ethyl sulfite is as follows Figure 1-2 As shown, its NMR data are as follows: 1H NMR (400MHz, CDCl3) δ7.36–7.32(m,4H),7.29–7.25(m,2H),7.23–7.21(m,4H),4.17–4.03(m,4H),2.95(t,J=6.8Hz,4H)ppm. 13 C NMR (101MHz, CDCl3) δ137.1,128.9,128.5,126.7,62.6,35.9ppm.

[0081] Example 2

[0082] Synthesis of Bis(4-bromophenethyl)sulfite

[0083] 2-(4-bromophenyl)ethan-1-ol (100.0 mg, 1 equiv.), Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and then evacuated and an SF6 balloon was inserted, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 37.2 mg of bis(4-bromophenylethyl)sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 50%.

[0084] The NMR spectrum of the product bis(4-bromophenethyl)sulfite is as follows Figure 3-4 As shown, its NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.43–7.41(m,4H),7.06–7.04(m,4H),4.09–3.94(m,4H),2.85(t,J=6.4Hz,4H)ppm. 13 C NMR (101MHz, CDCl3) δ136.1, 131.6, 130.6, 120.7, 62.2, 35.2ppm.

[0085] Example 3

[0086] Synthesis of Bis(2-(Thien-2-yl)ethyl)sulfite

[0087] 2-(Thien-2-yl)ethan-1-ol (64.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and then evacuated and an SF6 balloon was inserted, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 30.6 mg of bis(2-(thien-2-yl)ethyl)sulfite was obtained by silica gel column chromatography (petroleum ether:ethyl acetate volume ratio = 20:1), with a yield of 68%.

[0088] The NMR spectrum of the product bis(2-(thiophen-2-yl)ethyl)sulfite is as follows Figure 5-6 As shown, its NMR data are as follows: 1 HNMR (400MHz, CDCl3) δ7.18–7.17(m,2H),6.96–6.94(m,2H),6.88–6.87(m,2H),4.21–4.07(m,4H),3.16(t,J=6.8Hz,4H)ppm. 13 C NMR (101MHz, CDCl3) δ139.0,126.9,125.8,124.2,62.4,30.1ppm.

[0089] Example 4

[0090] Synthesis of Bis(2-(Naphthyl-1-yl)ethyl)sulfite

[0091] 2-(Naphthalene-1-yl)ethan-1-ol (86.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and a SF6 balloon was inserted after vacuuming, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 33.8 mg of bis(2-(naphthalene-1-yl)ethyl)sulfite was obtained by silica gel column chromatography (petroleum ether:ethyl acetate volume ratio = 20:1), with a yield of 52%.

[0092] The NMR spectrum of the product bis(2-(naphthalen-1-yl)ethyl)sulfite is as follows Figure 7-8 As shown, its NMR data are as follows: 1HNMR(400MHz, CDCl3)δ7.99–7.97(m,2H),7.87–7.85(m,2H),7.76–7.74(m,2H),7.57–7.49 (m,4H),7.42–7.38(m,2H),7.32–7.30(m,2H),4.26–4.11(m,4H),3.37(t,J=7.2Hz,4H)ppm. 13 C NMR (101MHz, CDCl3) δ133.7,132.8,131.7,128.8,127.5,127.1,126.2,125.6,125.4,123.2,62.0,32.9ppm.

[0093] Example 5

[0094] Synthesis of Bis(cyclohexylmethyl)sulfite

[0095] Cyclohexylmethanol (57.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and a SF6 balloon was inserted after vacuuming. Then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15 W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 27.9 mg of bis(cyclohexylmethyl)sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 59%.

[0096] The NMR spectrum of the product bis(cyclohexylmethyl)sulfite is as follows Figure 9-10 As shown, its NMR data are as follows: 1 HNMR (400MHz, CDCl3) δ3.83–3.66(m,4H),1.75–1.57(m,12H),1.29–1.09(m,6H),1.01–0.91(m,4H)ppm. 13 C NMR (101MHz, CDCl3) δ67.0, 37.6, 29.4 (d, J = 5.6Hz), 26.2, 25.5ppm.

[0097] Example 6

[0098] Synthesis of di(pent-4-en-1-yl)sulfite

[0099] Pent-4-en-1-ol (43.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and then evacuated and an SF6 balloon was inserted, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15 W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 28.3 mg of di(pent-4-en-1-yl)sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 78%.

[0100] The NMR spectrum of the product di(pent-4-en-1-yl)sulfite is as follows Figure 11-12 As shown, its NMR data are as follows: 1 HNMR(400MHz, CDCl3)δ5.85–5.75(m,2H),5.10–5.08(m,1H),5.05–5.03(m,2H),5.01–5.0 0(m,1H),5.01–5.00(m,1H),4.08–3.92(m,4H),2.20–2.14(m,4H),1.82–1.75(m,4H)ppm. 13 CNMR (101MHz, CDCl3) δ137.0,115.6,61.5,29.7,28.6ppm.

[0101] Example 7

[0102] Synthesis of di(pent-4-yn-1-yl)sulfite

[0103] Pent-4-yn-1-ol (42.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and a SF6 balloon was inserted after vacuuming, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 15.3 mg of di(pent-4-yn-1-yl)sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 43%.

[0104] The NMR spectrum of the product di(pent-4-yn-1-yl)sulfite is as follows Figure 13-14 As shown, its NMR data are as follows:1 HNMR (400MHz, CDCl3) δ4.18–4.03(m,4H),2.35–2.31(m,4H),1.98(t,J=2.8Hz,2H),1.92–1.86(m,4H)ppm. 13 C NMR (101MHz, CDCl3) δ82.6, 69.3, 60.5, 28.2, 14.9ppm.

[0105] Example 8

[0106] Synthesis of Diethyl Sulfite

[0107] Ethanol (23.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and a SF6 balloon was inserted after vacuuming. Then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15 W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 14.7 mg of diethyl sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 64%.

[0108] The NMR spectrum of the product diethyl sulfite is as follows Figure 15-16 As shown, its NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ3.99–3.82(m,2H),1.21–1.15(m,3H)ppm. 13 C NMR (101MHz, CDCl3) δ57.8, 14.9ppm.

[0109] Example 9

[0110] Synthesis of 4-phenyl-1,3,2-dioxasulfane-2-oxide

[0111] 1-Phenylethane-1,2-diol (69.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and then evacuated and an SF6 balloon was inserted, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 33.1 mg of 4-phenyl-1,3,2-dioxasulfane-2-oxide was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 67%.

[0112] The NMR spectrum of the product 4-phenyl-1,3,2-dioxasulfane-2-oxide is as follows Figure 17-18 As shown, its NMR data are as follows: Major isomer: 1 H NMR (400MHz, CDCl3) δ7.45–7.35(m,5H),5.94(t,J=6.8Hz,1H),4.97–4.93(m,1H),4.22–4.18(m,1H)ppm. 13 C NMR (101MHz, CDCl3) δ134.4,129.5,129.0,126.5,80.8,73.4ppm.Minor isomer: 1 H NMR (400MHz, CDCl3) δ7.51–7.49(m,2H),7.46–7.36(m,3H),5.44–5.40(m,1H),4.78–4.74(m,1H),4.51–4.46(m,1H)ppm. 13 CNMR (101MHz, CDCl3) δ133.79,129.4,129.0,127.5,85.5,71.4ppm.

[0113] Example 10

[0114] Synthesis of 1,5-dihydrobenzo[e][1,3,2]dioxythiophene-3-oxide

[0115] 1,2-Benzenedimethanol (69.0 mg, 1 equiv.) and Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and then evacuated and an SF6 balloon was inserted. Then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15 W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 41.7 mg of 1,5-dihydrobenzo[e][1,3,2]dioxythiophene-3-oxide was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 68%.

[0116] The NMR spectrum of the product 1,5-dihydrobenzo[e][1,3,2]dioxythiophene-3-oxide is as follows Figure 19-20 As shown, its NMR data are as follows: 1 H NMR (400MHz, CDCl3) δ7.31–7.28(m,2H),7.25–7.24(m,2H),5.97–5.93(m,2H),4.70–4.66(m,2H)ppm. 13 C NMR (101MHz, CDCl3) δ136.2, 128.4, 128.4, 62.8ppm.

[0117] Embodiment 11

[0118] Synthesis of Dicyclohexyl Sulfite

[0119] Cyclohexanol (50.0 mg, 1 equiv.), p-trifluoromethylbenzoic acid (95.0 mg, 1 equiv.), Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8 mg, 0.5 mol%) were added to a 12 mL headspace glass bottle with a PTFE gasket, and a SF6 balloon was inserted after vacuuming, and then 3.0 mL of anhydrous tetrahydrofuran was added and bubbled for 3 minutes. Subsequently, diisopropylethylamine (434.6 μL, 5 equiv.) was added, and the reaction system was placed under 15 W, 465 nm blue LED light source and stirred for 20 hours. After the reaction was completed, the organic solvent was removed under vacuum, and 25.4 mg of dicyclohexyl sulfite was obtained by silica gel column chromatography (petroleum ether: ethyl acetate volume ratio = 20:1), with a yield of 62%.

[0120] The NMR spectrum of dicyclohexyl sulfite is as follows Figure 21-22 As shown, its NMR data are as follows: 1H NMR (400MHz, CDCl3) δ4.53–4.46(m,2H),1.91–1.85(m,4H),1.78–1.71(m,4H),1.58–1.46(m,6H),1.39–1.18(m,6H)ppm. 13 C NMR (101MHz, CDCl3) δ73.1, 33.4, 25.1, 23.8ppm.

[0121] In the above-mentioned Examples 1-11, stirring was carried out at room temperature under SF6 gas at one atmosphere pressure.

[0122] The structural formula and yield of the products of each embodiment are shown in the following table:

[0123]

[0124]

[0125] As can be seen from Examples 1-11, the present invention uses a simple and readily available alcohol as a reaction substrate, commercially available Ir[dF(CF3)ppy]2(dtbbpy)PF6 as a photocatalyst, and cheap and readily available N,N-diisopropylethylamine as a base, reacts at room temperature, and uses 15W 465nm blue light as a light source under an atmospheric pressure of SF6 gas to obtain the sulfite compounds. This method can obtain sulfite compounds well for aliphatic primary alcohols with aromatic rings or heteroaromatic rings (Examples 1-4), and primary alcohols with aliphatic six-membered rings (Example 5), double bonds (Example 6) and triple bonds (Example 7) are not affected in the reaction. In addition, diol compounds (Examples 9-10) obtain corresponding products in an intramolecular cyclization manner. For secondary alcohols (Example 11), corresponding products can also be obtained by adding additives such as benzoic acid. Diethyl sulfite DES (Example 8) obtained from ethanol is an organic solvent and lithium battery electrolyte additive widely used in the field of synthesis. Therefore, there is no particularly strict restriction on the type of alcohol compound and the number and type of its substituents. Therefore, this is a general synthesis method of sulfite compounds with mild conditions, simple operation and easy industrial promotion.

[0126] According to the steps of Example 1, the alcohol is replaced, and the yield is shown in the following table:

[0127]

[0128] Serial number 1 Yield (%) 1 phenol 0 2 Cyclohexanol 0 <![CDATA[3 a ]]> Cyclohexanol 31 <![CDATA[4 b ]]> Cyclohexanol 51 <![CDATA[5 c ]]> Cyclohexanol 62

[0129] Standard conditions: alcohol (0.5mmol, 1equiv.), Ir[dF(CF3)ppy]2(dtbbpy)PF6 (2.8mg, 0.5mol%), SF6 (1atm), tetrahydrofuran (3mL), diisopropylethylamine (2.5mmol, 5equiv.), 15W, 465nm blue LED light source irradiation, 20 hours. a: additional benzoic acid (0.5mmol, 1equiv.) was added. b: additional p-cyanobenzoic acid (0.5mmol, 1equiv.) was added. c: additional p-trifluoromethylbenzoic acid (0.5mmol, 1equiv.) was added.

[0130] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for synthesizing a sulfite compound, characterized in that: The method uses an alcohol compound as a raw material, sulfur hexafluoride as a sulfenylating agent, and an organic solvent as a reaction solvent, and performs a light irradiation reaction in the presence of a photocatalyst and a base to obtain the sulfite compound; Wherein, the alcohol compound is a monohydric alcohol or a dihydric alcohol; when the monohydric alcohol is a dihydric alcohol, a benzoic acid compound is added as an additive.

2. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The structural formula of the monohydric alcohol is R-OH, wherein R is selected from a C2-C7 pure alkyl group, a C3-C6 cycloalkyl group, a C2-C5 alkyl group containing an alkenyl or alkynyl group, a C2-C 20 The alkyl group The aromatic group is one of a Br-substituted benzene ring, a five-membered heterocyclic ring containing an S atom, a rigid naphthalene ring, and a benzene ring.

3. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The monohydric alcohol is one of phenylethyl alcohol, 2-(4-bromophenyl)ethane-1-ol, 2-(thiophen-2-yl)ethane-1-ol, 2-(naphthalene-1-yl)ethane-1-ol, cyclohexylmethanol, pent-4-en-1-ol, pent-4-yn-1-ol, ethanol, and cyclohexanol.

4. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The diol is 1-phenylethane-1,2-diol or 1,2-benzenedimethanol.

5. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The benzoic acid compound is a mixture of one or more of benzoic acid, p-trifluoromethylbenzoic acid and p-cyanobenzoic acid.

6. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The organic solvent is a mixture of one or more of tetrahydrofuran, acetonitrile or dichloromethane.

7. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The photocatalyst is 4CZIPN, Mes-Acr + A mixture of one or more of ClO4ˉ, Ir[dF(CF3)ppy]2(dtbbpy)PF6, and Ir(dtbbpy)ppy2PF6.

8. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The base is N,N-diisopropylethylamine.

9. The method for synthesizing sulfite compounds according to claim 1, characterized in that: During the photoreaction process, blue light of 450-480 nm was used as the light source.

10. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The reaction temperature is 0-50°C, the reaction time is 5-48h, and the sulfur hexafluoride gas pressure is 1-3atm.

11. The method for synthesizing sulfite compounds according to claim 1, characterized in that: The molar ratio of the base to the alcohol compound is 2:1 to 5:1; the molar ratio of the photocatalyst to the alcohol compound is 0.010:1 to 0.002:

1.

12. The method for synthesizing a sulfite compound according to any one of claims 1 to 11, characterized in that: The usage ratio of the alcohol compound and the organic solvent is 0.25-0.10 mmol:1 mL.

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