CN114032567A

CN114032567A - Electrochemical reduction carboxylation method based on non-sacrificial anode strategy

Info

Publication number: CN114032567A
Application number: CN202111397183.1A
Authority: CN
Inventors: 余达刚; 孙国权; 李立; 张伟; 廖黎丽
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2021-11-23
Filing date: 2021-11-23
Publication date: 2022-02-11

Abstract

The invention discloses an electrochemical reduction carboxylation method based on a non-sacrificial anode strategy, belonging to the field of electrochemical synthesis, and the method comprises the following steps: using a divided electrolytic cell as an electrolytic device, using a non-metal electrode/inert electrode as a cathode material and an anode material, adding a halogen salt and a reducing agent into an anode chamber, adding an organic halide or a pseudohalide, a nickel catalyst, a ligand, alkali and an electrolyte into a cathode chamber, and adding CO into the anode chamber₂Adding a solvent in the atmosphere, stirring and dissolving, introducing constant voltage between two electrodes for reaction, separating and purifying to obtain a target product; the method replaces the traditional sacrificial anode strategy with the non-sacrificial anode strategy of the oxidation reaction of the reducing agent generated by the anode, and solves the problems of higher reaction cost, higher pollution, higher residual quantity of product metal and the like in the traditional electrochemical synthesis process.

Description

Electrochemical reduction carboxylation method based on non-sacrificial anode strategy

Technical Field

The invention relates to the technical field of electrochemical synthesis, in particular to an electrochemical reduction carboxylation method based on a non-sacrificial anode strategy.

Background

The electrochemical carboxylation is a carboxylation method widely applied to bulk chemicals such as unsaturated hydrocarbons, halogenated substances, pseudo-halogenated substances, aromatic compounds and the like, and by utilizing the method, the construction of various carboxylic acid compounds can be efficiently and economically realized. However, at present, a sacrificial anode strategy (the sacrificial anode strategy is a strategy of providing electrons required in the process of cathode reduction reaction by using metals with strong reducibility, such as copper, aluminum or zinc, as an anode in the electrolytic process) is commonly used in the electro-synthesis process, and as the reaction is continuously carried out, the anode continuously gives out electron melting consumption, so the sacrificial anode is called), for example, patent CN111254457A, an electrochemical synthesis method of aromatic carboxylic acid and alkyl carboxylic acid, and the like, have the problems of high reaction cost, large pollution, high residual quantity of product metals, and the like. In order to solve the problems of the current electro-synthesis process, it is important to use a non-metal reducing agent instead of metal anodic oxidation.

There is currently no report on an electrochemical carboxylation process that replaces the traditional sacrificial anode strategy with a non-sacrificial anode strategy where oxidation of the reducing agent occurs at the anode.

Disclosure of Invention

In view of the above-mentioned disadvantages, it is an object of the present invention to provide a process for electrochemical reductive carboxylation based on a non-sacrificial anodic strategy. The method replaces the traditional sacrificial anode strategy with a non-sacrificial anode strategy in which the anode is oxidized by a reducing agent, replaces the oxidation reaction of a metal anode in the traditional electrosynthesis by utilizing reactions such as anode aromatic hydrocarbon oxidation halogenated coupling or amine compound oxidation and the like, effectively solves the problems of large electrode loss, high synthesis cost, high product metal residue and the like in the existing electrosynthesis process, successfully realizes that two different target products can be obtained by the cathode and the anode simultaneously, and has higher practical application value.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides an electrochemical reduction carboxylation method based on a non-sacrificial anode strategy, which comprises the following steps: using a divided electrolytic cell as an electrolytic device, using a non-metal electrode as a cathode material and an anode material, adding a halogen salt and a reducing agent into an anode chamber, adding an organic halide or a pseudohalide, a nickel catalyst, a ligand, alkali and a supporting electrolyte into a cathode chamber, and adding CO into the anode chamber₂Under the atmosphere addAnd (3) adding a solvent, stirring and dissolving, introducing constant voltage between two electrodes for reaction, separating and purifying to obtain the target product.

It should be noted that, the present invention is improved on the basis of the prior art patent CN 111254457A-an electrochemical synthesis method of aromatic carboxylic acid and alkyl carboxylic acid, and uses a divided electrolytic cell as an electrolytic device, the anode material adopts a non-metal electrode such as carbon felt, and halogen salt and a reducing agent are added into an anode chamber, so that an oxidation reaction of the reducing agent occurs in the anode chamber, the oxidation reaction of a metal anode in the conventional electrosynthesis is replaced by an oxidation mode of the anode reducing agent, a non-sacrificial anode electrochemical carboxylation method is realized, and finally, oxidation products of the corresponding carboxylic acid and the corresponding reducing agent are respectively prepared at the anode and the cathode.

Further, the electrochemical reduction carboxylation method based on the non-sacrificial anode strategy specifically comprises the following steps:

s1, adding an organic halide or a pseudohalide, a nickel catalyst, a ligand, an alkali and a supporting electrolyte into a cathode chamber of an H-shaped partition electrolytic cell of which two sides are fixed with non-metal electrodes under the inert gas atmosphere, and then adding a halogen salt into an anode chamber of the H-shaped partition electrolytic cell;

s2 in CO₂Adding a solvent into the H-shaped segmentation electrolytic cell treated by the S1 under the gas atmosphere, stirring and dissolving, adding a reducing agent into the anode chamber, introducing constant voltage between the two electrodes for reaction, separating and purifying to obtain a target product.

Further, the halogen salt is added in the anode chamber in an amount of 10 to 200% molar equivalent, preferably 60% molar equivalent of the organic halide or pseudohalide; the amount of reducing agent added to the anode compartment is 100-400%, preferably 200% molar equivalents of the organic halide or pseudohalide.

Furthermore, the reducing agent added into the anode chamber is aromatic hydrocarbon, amine compound, (thio) alcohol, phenol and the like; wherein, the aromatic hydrocarbon includes but is not limited to mono-substituted benzene and poly-substituted benzene such as benzene, toluene, ethylbenzene, propylbenzene, butylbenzene, xylene, trimethylbenzene, tetramethylbenzene, pentamethylene, hexamethylbenzene or condensed ring compounds such as naphthalene, anthracene, phenanthrene or substituted condensed ring compounds; the amine compound includes alkylamine but not limited to methylamine, ethylamine, propylamine, butylamine or di-substituted amine but not limited to dimethylamine, diethylamine, dipropylamine, dibutylamine and the like or tri-substituted amine but not limited to triethylamine, triethanolamine, diisopropylethylamine, N-tetramethylethylenediamine, triethylenediamine and the like or arylamine but not limited to aniline, N-methylaniline, N-dimethylaniline and the like or multi-substituted arylamine; (thio) alcohols include alcohol compounds and thiol compounds but are not limited to alkyl alcohols and alkyl thiols; the (thio) phenols include benzenethiol and polysubstituted benzenethiol but are not limited to methylbenzophenol (thio) phenol, naphthalenepolyol, and the like.

Further, the halogen salt in S1 includes at least one of inorganic chloride salt, inorganic bromide salt, inorganic iodide salt and organic halogen salt; further, inorganic chloride salts include, but are not limited to, lithium chloride, sodium chloride, and the like; inorganic bromine salts include, but are not limited to, lithium bromide, sodium bromide, and the like; inorganic iodine salts include, but are not limited to, lithium iodide, sodium iodide, and the like; organic halogen salts include organic ammonium halides (phosphines) including, but not limited to, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetraethylammonium chloride, tetraethylphosphonium chloride, and the like.

Further, the organic halide or pseudohalide in S1 is aryl chloride, aryl bromide, aryl iodide, aryl sulfonate, alkyl bromide, alkyl iodide, alkyl sulfonate or alkyl chloride.

Further, preferred compound structural formulas of the organic halides or pseudohalides are as follows:

further, the amount of the nickel catalyst in S1 is 1 to 20% molar equivalent, preferably 5% molar equivalent, of the organohalide or pseudohalide; the amount of ligand is 1-40% molar equivalents, preferably 10% molar equivalents, of the organohalide or pseudohalide; the amount of base is from 0.1 to 3 times the molar equivalent of the organohalide or pseudohalide, preferably 200% molar equivalent; the electrolyte concentration is 0.05-0.4M, preferably 0.15M.

Further, the nickel catalyst in S1 comprises one or two of inorganic nickel salt and organic nickel complex; further, inorganic nickel salts include, but are not limited to, nickel chloride, nickel bromide, nickel iodide, nickel perchlorate, and hydrates thereof; organic nickel complexes include, but are not limited to, nickel chloride ethylene glycol dimethyl ether adduct, nickel bromide diethylene glycol dimethyl ether adduct, bis- (1, 5-cyclooctadiene) nickel or nickel acetylacetonate, and the like; preferably a nickel bromide glyme adduct or nickel acetylacetonate.

Further, the ligand in S1 includes at least one of a polysubstituted 2, 2' -bipyridine compound, a polysubstituted phenanthroline compound and a polysubstituted pyridine compound; further, R in the polysubstituted 2, 2' -bipyridine compound¹，R²，R³，R⁴The substituent is not limited to a hydrogen atom, an aryl group, an alkyl group, an alkoxy (nitrogen, sulfur, phosphine) group, a halogen atom, or the like; r in multi-substituted phenanthroline compound¹，R²，R³，R⁴The substituent is not limited to a hydrogen atom, an aryl group, an alkyl group, an alkoxy (nitrogen, sulfur, phosphine) group, a halogen atom, or the like; r in polysubstituted pyridine compound¹，R²，R³，R⁴，R⁵The substituent is not limited to a hydrogen atom, an aryl group, an alkyl group, an alkoxy (nitrogen, sulfur, phosphine) group, a halogen atom, or the like; preferred are 4,4 '-di-tert-butyl-2, 2' -bipyridine and 6, 6 '-dimethyl-2, 2' -bipyridine; the structural general formulas of the 2, 2' -bipyridyl compound, the polysubstituted phenanthroline compound and the polysubstituted pyridine compound are respectively as follows:

further, the base in S1 includes one or both of an inorganic base and an organic base; further, inorganic bases include, but are not limited to, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium carbonate, potassium phosphate, potassium dihydrogen phosphate, potassium hydrogen phosphate, sodium dihydrogen phosphate, sodium hydrogen phosphate, sodium fluoride, potassium fluoride, cesium fluoride, and the like; organic bases include, but are not limited to, sodium methoxide, potassium methoxide, sodium ethoxide, lithium tert-butoxide, sodium tert-butoxide, potassium tert-butoxide, 1, 8-diazohetero-bis-spiro [5.4.0] undec-7-ene, 157-triazabicyclo (4.4.0) dec-5-ene, and the like; preferably sodium tert-butoxide or cesium fluoride.

Further, the electrolyte in S1 includes at least one of an inorganic halogen-containing salt, an organic ammonium salt, and an ionic liquid; still further, inorganic halogen-containing salts include, but are not limited to, sodium iodide, lithium bromide, lithium chloride, sodium chloride, lithium iodide, lithium perchlorate; organic ammonium salts include, but are not limited to, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetrabutylammonium tetrafluoroborate, tetrabutylammonium hexafluorophosphate, tetrabutylammonium perchlorate, tetraethylammonium chloride, tetraethylammonium bromide, and the like; ionic liquids include, but are not limited to, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium nitrate, 1-butyl-3-methylimidazolium hydrogen sulfate, 1-butyl-3-methylimidazolium perchlorate, 1-butyl-3-methylimidazolium trifluoroacetate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, and mixtures thereof, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-octyl-3-methylimidazolium tetrafluoroborate, and the like; sodium iodide or lithium perchlorate is preferred.

Further, the solvent in S2 includes at least one of a pyrrolidone organic solvent, an amide organic solvent, a sulfoxide organic solvent, an imidazolone organic solvent, a nitrile organic solvent, an alcohol organic solvent, a paraffin organic solvent, a substituted paraffin organic solvent, an ester organic solvent, a furan organic solvent, and water; the reducing agent comprises aromatic hydrocarbon, amine compound, alcohol, phenol or mercaptan; further, solvents include, but are not limited to, N-methylpyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethylsulfoxide, 1, 3-dimethyl-2-imidazolidinone, acetonitrile, methanol, dichloromethane, ethyl acetate, tetrahydrofuran, water, and the like; n-methylpyrrolidone is preferred.

Further, the reaction parameters in S2 are: the reaction constant voltage is 0.5-10V; the reaction time is 0.5-48 h; the reaction temperature is 0-100 ℃, and more preferably 25 ℃; further, the reaction parameters in S2 are: the reaction constant voltage is 1-5V; preferably 3V; the reaction time is 10-24h, preferably 24 h; the reaction temperature is 25-60 ℃; preferably 25-45 deg.c.

Further, the non-metal electrode/inert electrode includes one or both of a carbon-based material electrode and an inert metal electrode; further, carbon-based material electrodes include, but are not limited to, graphite electrodes, glassy carbon electrodes, carbon felt electrodes, carbon paper electrodes, carbon cloth electrodes, and the like; preferably a carbon felt; inert metal electrodes include, but are not limited to, platinum electrodes, gold electrodes, niobium electrodes, and the like.

In summary, the invention has the following advantages:

1. the invention provides an electrochemical reduction carboxylation method based on a non-sacrificial anode strategy. The method replaces the traditional sacrificial anode strategy with a non-sacrificial anode strategy in which an anode reducing agent is subjected to oxidation reaction, particularly replaces the oxidation reaction of a metal anode in the traditional electrosynthesis by adopting a reaction mode of oxidizing halogenated coupling with anode aromatic hydrocarbon or oxidizing amine compounds and the like, effectively solves the problems of large electrode loss, high synthesis cost, high product metal residue and the like in the existing electrosynthesis process, successfully achieves the aim of obtaining two different products from a cathode and an anode simultaneously, and has higher practical application value.

2. Compared with the prior art (for example, patent CN111254457A — an electrochemical synthesis method of aromatic carboxylic acid and alkyl carboxylic acid), the present invention uses the divided electrolytic cell as an electrolytic device, the anode material adopts a non-metal electrode such as carbon felt, and the halogen salt and the reducing agent such as toluene or amine compound are added into the anode chamber, so that the reducing agent oxidation reaction occurs in the anode chamber, for example, the oxidation reaction of the metal anode in the traditional electrosynthesis is replaced by the reaction of anode arene oxidation halogenated coupling or amine compound oxidation, and thus, the corresponding carboxylic acid product and the corresponding oxidation product of the reducing agent such as 1, 2-diphenylethane/imine compound are simultaneously prepared at the cathode and the anode respectively, and the synthesis efficiency is higher; and the quality of the anode material after the reaction is finished can not be obviously changed, and the obtained product metal residue is lower, so that the problems of higher reaction cost, higher pollution, higher product metal residue and the like in the traditional electrochemical synthesis process are solved.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

Thus, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

4-phenoxybromobenzene 1d (0.3mmol), nickel acetylacetonate (0.3mmol), ligand 4,4 '-di-tert-butyl-2, 2' -bipyridine (0.03mmol) and potassium tert-butoxide (0.15mmol) are sequentially added in an H-shaped partition pool (a carbon felt electrode and a carbon felt electrode are fixed in two reaction chambers of the partition pool),

molecular sieve (100mg), sodium iodide (1mmol) was added to the cathode compartment; adding lithium chloride (0.18mmol) into the anode chamber of the H-shaped partition cell; the above operations are completed in the glove box; after the device is taken out from the glove box in a sealed way, the nitrogen in the reaction bottle is pumped and replaced into CO through the double-row gas guide system₂(five iterations each lasting 1 minute) followed by CO₂Under the atmosphere, 6mL of ultra-dry N-methylpyrrolidone (NMP) is sequentially added into the cathode chamber and the anode chamber by using an injector; the stirrer was started until all solids had dissolved, after which time CO was added₂Adding ultra-dry toluene (0.6mmol) into the anode chamber by a syringe under an atmosphere; subsequently, the electrodes were immersed into the solution (the effective immersion volumes of the carbon felt electrodes in the cathodic and anodic compartments were all about 1X 1cm 3); at room temperature, a constant bath pressure of 3V was set for 24h of electrolytic reaction. After the reaction is finished, about 20mL of 2N hydrochloric acid aqueous solution is respectively added into the cathode chamber and the anode chamber to be acidified for about 1h, and at the moment, the carbon felt electrode needs to be completely immersed into the hydrochloric acid solution. After the acidification is finished, extracting the reaction solution by using ethyl acetate, combining organic layers, washing NMP in the organic layer by using water (2X 20mL) and saturated ammonium chloride solution (20mL), combining the washed organic layers, concentrating and spin-drying the reaction solution, and separating by using a column chromatography mode (eluent is a mixture of petroleum ether, ethyl acetate and glacial acetic acid, and the glacial acetic acid in the mixture is 0.4 vt%) to obtain a target carboxylic acid (4-phenoxybenzoic acid) and a 1, 2-diphenylethane product; the target carboxylic acid was finally obtained in 84% yield and 1, 2-diphenylethane product in 51% yield without loss of the electrode.

Example 2

4-phenyl bromobenzene 1b (0.3mmol), nickel acetylacetonate (0.3mmol), ligand 4,4 '-di-tert-butyl-2, 2' -bipyridine (0.03mmol) and potassium tert-butoxide (0.15mmol) are sequentially added in an H-shaped partition pool (a carbon felt electrode and a carbon felt electrode are fixed in two reaction chambers of the partition pool),

molecular sieve (100mg), sodium iodide (1mmol) was added to the cathode compartment; adding lithium chloride (0.18mmol) into the anode chamber of the H-shaped partition cell; the above operations are completed in the glove box; after the device is taken out from the glove box in a sealed way, the nitrogen in the reaction bottle is pumped and replaced into CO through the double-row gas guide system₂(five iterations each lasting 1 minute) followed by CO₂Under the atmosphere, 6mL of ultra-dry N-methylpyrrolidone (NMP) is sequentially added into the cathode chamber and the anode chamber by using an injector; the stirrer was started until all solids had dissolved, after which time CO was added₂Under the atmosphere using a syringe toTriethylamine (0.6mmol) is added into the anode chamber; subsequently, the electrodes were immersed into the solution (the effective immersion volumes of the carbon felt electrodes in the cathodic and anodic compartments were all about 1X 1cm 3); at room temperature, a constant bath pressure of 3V was set for 24h of electrolytic reaction. After the reaction is finished, about 20mL of 2N hydrochloric acid aqueous solution is respectively added into the cathode chamber and the anode chamber to be acidified for about 1h, and at the moment, the carbon felt electrode needs to be completely immersed into the hydrochloric acid solution. After the acidification is finished, extracting the reaction solution by using ethyl acetate, combining organic layers, washing NMP in the organic layer by using water (2X 20mL) and saturated ammonium chloride solution (20mL), combining the washed organic layers, concentrating and spin-drying the reaction solution, and separating by using a column chromatography mode (eluent is a mixture of petroleum ether, ethyl acetate and glacial acetic acid, and the glacial acetic acid in the mixture is 0.4 vt%) to obtain a target carboxylic acid (4-phenylbenzoic acid) and an imine product; finally, the target carboxylic acid was obtained in 84% yield and the imine product was obtained in 45% yield without loss of the electrode.

Example 3

Bromobenzene 1a (0.3mmol), nickel acetylacetonate (0.3mmol), ligand 4,4 '-di-tert-butyl-2, 2' -bipyridine (0.03mmol) and potassium tert-butoxide (0.15mmol) are sequentially added in an H-shaped partition pool (a carbon felt electrode and a carbon felt electrode are fixed in two reaction chambers of the partition pool),

molecular sieve (100mg), sodium iodide (1mmol) was added to the cathode compartment; adding lithium chloride (0.18mmol) into the anode chamber of the H-shaped partition cell; the above operations are completed in the glove box; after the device is taken out from the glove box in a sealed way, the nitrogen in the reaction bottle is pumped and replaced into CO through the double-row gas guide system₂(five iterations each lasting 1 minute) followed by CO₂Under the atmosphere, 6mL of ultra-dry N-methylpyrrolidone (NMP) is sequentially added into the cathode chamber and the anode chamber by using an injector; the stirrer was started until all solids had dissolved, after which time CO was added₂Adding benzyl alcohol (0.6mmol) into the anode chamber by a syringe under the atmosphere; subsequently, the electrodes were immersed into the solution (the effective immersion volumes of the carbon felt electrodes in the cathodic and anodic compartments were all about 1X 1cm 3); at room temperature, a constant bath pressure of 3V was set for 24h of electrolytic reaction. After the reaction is finished, the anode and the cathode are switchedThe chambers were each acidified for about 1h by adding about 20mL of 2N aqueous hydrochloric acid solution, at which time the carbon felt electrodes were completely immersed in the hydrochloric acid solution. After the acidification is finished, extracting the reaction solution by using ethyl acetate, combining organic layers, washing NMP in the organic layer by using water (2X 20mL) and saturated ammonium chloride solution (20mL), combining the washed organic layers, concentrating and spin-drying the reaction solution, and separating by using a column chromatography mode (eluent is a mixture of petroleum ether, ethyl acetate and glacial acetic acid, and the glacial acetic acid in the mixture is 0.4 vt%) to obtain the target carboxylic acid benzoic acid; finally, the target carboxylic acid was obtained in a yield of 32% without loss of the electrode.

Example 4

In this example, 4-phenoxybromobenzene 1d was replaced by compounds 1a to 1c and 1c to 1ag (shown below) based on example 1, and the remaining steps and parameters were the same, and the reaction results were as follows:

when the reaction substrates are different, the yield interval of the obtained carboxylic acid product is 11-90%.

Example 5

In this example, based on example 1, the reaction parameters were varied by a single variable control method using compounds 1a, 1o and 1m as reaction substrates. The method specifically comprises the following steps:

(1) the amount of nickel catalyst is adjusted to 1%, 10% or 20% molar equivalents of the reaction substrate; the amount of ligand is adjusted to 1%, 30% or 40% molar equivalents of the reaction substrate; the amount of the base is adjusted to 50% molar equivalent or 300% molar equivalent of the reaction substrate; the supporting electrolyte concentration is 0.05M, 0.2M or 0.4M.

(2) The nickel catalyst is adjusted to nickel bromide, nickel chloride ethylene glycol dimethyl ether adduct or nickel bromide ethylene glycol dimethyl ether adduct.

(3) The ligand is adjusted to be 2,2 ' -bipyridyl, 6 ' -dimethoxy-2, 2 ' -bipyridyl, 4 ' -dimethoxy-2, 2 ' -bipyridyl or 4,4 ' -di-tert-butyl-2, 2 ' -bipyridyl.

(3) The base is adjusted to cesium fluoride or sodium ethoxide.

(4) The supporting electrolyte is adjusted to be lithium perchlorate, tetrabutylammonium tetrafluoroborate, lithium bromide, lithium chloride or lithium iodide.

(5) The solvent is adjusted to N, N-dimethylacetamide, dimethylsulfoxide, 1, 3-dimethyl-2-imidazolidinone or acetonitrile.

(6) In S2, the reaction parameters are adjusted as follows: the reaction constant voltage is 0.5V or 6V; the reaction time is 5h and 10 h; the reaction temperature was 10 ℃ or 60 ℃.

(7) The reducing agent is adjusted to triethanolamine, N-tetramethylethylenediamine, ethylbenzene, benzene (sulfur) phenol or alkyl alcohol.

Test results show that the compounds 1a, 1o and 1m can smoothly react, the yield interval of the carboxylic acid product obtained from 1a is 71-81%, the yield interval of the carboxylic acid product obtained from 1o is 78-88%, and the yield interval of the carboxylic acid product obtained from 1m is 61-75%.

The characterization data of the product obtained in the invention are as follows:

¹H NMR(400MHz,CDCl₃):δ＝12.83(s,1H),8.12(dd,J＝8.2,0.9Hz,2H),7.65-7.49(m,1H),7.50-7.42(m,2H).

¹³C NMR(101MHz,CDCl₃):δ＝172.8,133.9,130.3,129.4,128.5.

Exact Mass ESI-MS:calculated m/z for[M-H+]:121.03,found:120.98.

4-Phenylbenzoic acid

8.4Hz,2H),7.80(d,J＝8.3Hz,2H),7.74(d,J＝7.6Hz,2H),7.51(t,J＝7.5Hz,2H),7.43(t,J＝7.3Hz,1H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.6,144.8,139.5,130.4,130.1,129.5,128.7,127.4,127.3.

Exact Mass ESI-MS:calculated m/z for[M-H+]:197.06,found:196.94.

4- (1-hydroxybenzyl) benzoic acid

＝8.3Hz,2H),7.47(d,J＝8.2Hz,2H),7.37-7.32(m,2H),7.30-7.23(m,2H),7.20-7.14(m,1H),6.02(d,J＝3.8Hz,1H),5.73(d,J＝3.0Hz,1H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.6,151.0,145.5,129.7,129.6,128.6,127.4,126.7,126.7,74.3.

Exact Mass ESI-MS:calculated m/z for[M-H+]:227.07,found:226.99.

4-methoxybenzoic acid

3.88(s,3H).

¹³C NMR(101MHz,CDCl₃):δ＝171.5,164.0,132.4,121.6,113.8,55.5.

Exact Mass ESI-MS:calculated m/z for[M-H+]:151.04,found:150.98.

(1-methyl-1-carboxylethoxy) benzoic acid

2H),6.82(d,J＝8.8Hz,2H),4.21(q,J＝7.1Hz,2H),1.64(s,6H),1.19(t,J＝7.1Hz,3H).

¹³C NMR(101MHz,CDCl₃):δ＝173.7,171.7,160.3,131.9,122.2,117.2,79.3,61.7,25.3,14.0.

Exact Mass ESI-MS:calculated m/z for[M-H+]:251.0925,found:251.0929.

4-Carboxylic acid methyl ester benzoic acid

¹H NMR(400MHz,DMSO-d₆):δ＝13.38(s,1H),8.42-7.85(m,4H),3.89(s,3H).

¹³C NMR(101MHz,DMSO-d₆):δ＝169.1,166.3,139.0,132.4,130.0,129.4,52.7.

Exact Mass ESI-MS:calculated m/z for[M-H+]:179.03,found:178.96.

2-acetylbenzoic acid

1H),8.28-8.14(m,2H),7.67(t,J＝7.7Hz,1H),2.64(s,3H).

¹³C NMR(101MHz,DMSO-d₆):δ＝197.8,167.1,137.4,134.0,132.8,131.7,129.7,129.1,27.3.

Exact Mass ESI-MS:calculated m/z for[M-H+]:163.04,found:162.98.

2-naphthoic acid

¹H NMR(400MHz,DMSO-d₆):δ＝13.06(s,1H),8.64(s,1H),8.13(d,J＝7.7Hz,1H),8.07-7.95(m,3H),7.72-7.56(m,2H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.9,135.4,132.6,131.0,129.7,128.8,128.6,128.5,128.1,127.3,125.6.

Exact Mass ESI-MS:calculated m/z for[M-H+]:171.05,found:170.98.

1-naphthoic acid

Hz,1H),8.16(d,J＝7.3Hz,2H),8.03(d,J＝7.7Hz,1H),7.71-7.53(m,3H).

¹³C NMR(101MHz,DMSO-d₆):δ＝169.1,139.9,133.4,131.2,130.3,129.1,128.2,128.0,126.7,126.0,125.4.

Exact Mass ESI-MS:calculated m/z for[M-H+]:171.05,found:170.93.

4-Phenoxybenzoic acid

(t,J＝7.9Hz,2H),7.21(t,J＝7.4Hz,1H),7.09(d,J＝7.8Hz,2H),7.01(d,J＝8.8Hz,2H).

¹³C NMR(101MHz,CDCl₃):δ＝171.6,162.7,155.4,132.5,130.1,124.7,123.4,120.3,117.2.

Exact Mass ESI-MS:calculated m/z for[M-H+]:213.06,found:212.97.

4-methylthiobenzoic acid

(d,J＝8.6Hz,2H),2.53(s,3H).

¹³C NMR(101MHz,CDCl₃):δ＝171.3,146.7,130.5,125.2,124.9,14.8.

Exact Mass ESI-MS:calculated m/z for[M-H+]:167.02,found:166.97.

4-hydroxymethylbenzoic acid

＝8.2Hz,2H),7.43(d,J＝8.1Hz,2H),5.32(s,1H),4.57(s,2H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.8,148.3,129.7,129.6,126.6,62.9.Exact Mass ESI-MS:calculated m/z for[M-H+]:151.04,found:150.95.

3-methoxybenzoic acid

(dd,J＝2.4,1.5Hz,1H),7.39(t,J＝7.9Hz,1H),7.16(ddd,J＝13.2,7.0,1.1Hz,1H),3.87(s,3H).

¹³C NMR(101MHz,CDCl₃):δ＝172.3,159.6,130.6,129.6,122.7,120.5,114.4,55.5.

Exact Mass ESI-MS:calculated m/z for[M-H+]:151.04,found:150.98.

3-Benzyloxybenzoic acid

7.49-7.44(m,2H),7.44-7.38(m,3H),7.36(dd,J＝5.9,4.3Hz,1H),7.23(ddd,J＝8.3,2.5,0.9Hz,1H),5.13(s,2H).

¹³C NMR(101MHz,CDCl₃):δ＝158.8,136.5,130.6,129.6,128.7,128.2,127.6,123.0,121.2,115.5,100.0,70.2.

Exact Mass ESI-MS:calculated m/z for[M-H+]:227.07,found:226.98.

2-Phenylbenzoic acid

1H),7.58-7.51(m,1H),7.47-7.26(m,7H).

¹³C NMR(101MHz,DMSO-d₆):δ＝170.2,141.4,141.3,132.8,131.3,130.9,129.5,128.8,128.6,127.7,127.6.

Exact Mass ESI-MS:calculated m/z for[M-H+]:197.06,found:196.96.

3, 5-diphenylbenzoic acid

10.2Hz,3H),7.82(d,J＝7.4Hz,4H),7.53(t,J＝7.5Hz,4H),7.44(t,J＝7.3Hz,2H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.6,141.9,139.7,132.7,129.9,129.6,128.5,127.6,126.9.

Exact Mass ESI-MS:calculated m/z for[M-H+]:273.09,found:272.98.

Pepper acid

8.1,1.7Hz,1H),7.36(d,J＝1.6Hz,1H),7.00(d,J＝8.1Hz,1H),6.12(s,2H).

¹³C NMR(101MHz,DMSO-d₆):δ＝166.6,151.1,147.4,124.9,124.6,108.7,108.0,101.9.

Exact Mass ESI-MS:calculated m/z for[M-H+]:165.02,found:164.99.

6-methoxy-naphthoic acid

(s,1H),8.02(d,J＝9.0Hz,1H),7.95(d,J＝8.4Hz,1H),7.88(d,J＝8.4Hz,1H),7.39(d,J＝1.6Hz,1H),7.24(dd,J＝8.9,2.2Hz,1H),3.90(s,3H).

¹³C NMR(101MHz,DMSO-d₆):δ＝159.6,137.2,131.4,130.9,128.0,127.4,126.3,119.9,106.4,55.8.

Exact Mass ESI-MS:calculated m/z for[M-H+]:201.06,found:201.03.

Dibenzothiophene 2-carboxylic acid

＝1.2Hz,1H),8.56-8.47(m,1H),8.16(d,J＝8.4Hz,1H),8.08(ddd,J＝8.5,5.4,1.8Hz,2H),7.64-7.52(m,2H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.8,143.8,139.4,135.5,135.1,128.1,128.0,127.8,125.7,123.7,123.6,123.5,122.9.

Exact Mass ESI-MS:calculated m/z for[M-H+]:227.0172,found:227.0167.

Diphenylfuran-2-carboxylic acid

J＝1.6Hz,1H),8.31(d,J＝7.4

Hz,1H),8.14(dd,J＝8.6,1.8Hz,1H),7.78(dd,J＝17.1,8.4Hz,2H),7.66-7.56(m,1H),7.46(t,J＝7.3Hz,1H).

¹³C NMR(101MHz,DMSO-d₆):δ＝167.6,158.4,156.5,129.5,128.7,126.4,124.3,124.1,123.5,123.5,122.2,112.3,112.1.

Exact Mass ESI-MS:calculated m/z for[M-H+]:211.04,found:211.01.

4-tert-butylbenzoic acid

(d,2H),1.35(s,9H).

¹³C NMR(101MHz,CDCl₃):δ＝171.9,157.6,130.1,126.5,125.5,35.2,31.1.Exact Mass ESI-MS:calculated m/z for[M-H+]:177.09,found:177.03.

4-Trifluoromethoxy carboxylic acid

(m,2H).

¹³C NMR(101MHz,CDCl₃):δ＝171.0,153.4,132.3,127.6,120.3(d,J＝259.0Hz),120.3.

¹⁹F NMR(376MHz,CDCl₃):δ＝-57.64.

Exact Mass ESI-MS:calculated m/z for[M-H+]:205.01,found:204.98.

3, 5-di-tert-butylbenzoic acid

J＝1.9Hz,1H),1.37(s,18H).

¹³C NMR(101MHz,CDCl₃):δ＝173.3,151.2,128.7,128.1,124.5,35.0,31.4.Exact Mass ESI-MS:calculated m/z for[M-H+]:233.15,found:233.05.

4-Trifluoromethylbenzoic acid

8.1Hz,2H),7.85(d,J＝8.2Hz,2H).

¹³C NMR(101MHz,DMSO-d₆):δ＝166.7,135.1,133.1,132.8,130.6,126.1(d,J＝3.6Hz).

¹⁹F NMR(376MHz,CDCl₃):δ＝-61.56.

Exact Mass ESI-MS:calculated m/z for[M-H+]:189.02,found:188.92.

7-pivaloyloxyheptanoic acid

¹H NMR(400MHz,CDCl₃):δ＝4.05(t,J＝6.6Hz,2H),2.36(t,J＝7.5Hz,2H),1.70-1.60(m,4H),1.42-1.36(m,4H),1.19(s,9H).

¹³C NMR(101MHz,CDCl₃):δ＝180.0,178.7,64.3,38.7,33.9,28.6,28.3,27.1,25.6,24.5.

Exact Mass ESI-MS:calculated m/z for[M-H+]:229.14,found:228.89.

7-Benzyloxyeheptanoic acid

¹H NMR(400MHz,CDCl₃):δ＝7.37-7.31(m,4H),7.30-7.25(m,1H),4.49(s,2H),3.45(t,J＝6.6Hz,2H),2.33(t,J＝7.5Hz,2H),1.70-1.56(m,4H),1.46-1.29(m,4H).

¹³C NMR(101MHz,CDCl₃):δ＝180.1,138.5,128.3,127.6,127.5,72.8,70.2,34.0,29.5,28.9,25.8,24.6.

Exact Mass ESI-MS:calculated m/z for[M-H+]:235.13,found:234.96.

4-Phenylbutyric acid

¹H NMR(400MHz,CDCl₃):δ＝7.24-7.17(m,2H),7.16-7.07(m,3H),2.59(t,2H),2.29(t,J＝7.4Hz,2H),1.95-1.82(m,2H).

¹³C NMR(101MHz,CDCl₃):δ＝180.2,141.2,128.5,128.4,126.0,35.0,33.4,26.2.

Exact Mass ESI-MS:calculated m/z for[M-H+]:163.08,found:162.92.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to supplement or replace the specific embodiments described by those skilled in the art without inventive faculty.

Claims

1. An electrochemical reduction carboxylation method based on a non-sacrificial anode strategy is characterized by comprising the following steps: using a divided electrolytic cell as an electrolytic device, using a non-metal electrode/inert electrode as a cathode material and an anode material, adding a halogen salt and a reducing agent into an anode chamber, adding an organic halide or a pseudohalide, a nickel catalyst, a ligand, alkali and an electrolyte into a cathode chamber, and adding CO into the anode chamber₂And adding a solvent in the atmosphere, stirring and dissolving, introducing constant voltage between two electrodes for reaction, separating and purifying to obtain the target product.

2. The non-sacrificial anode strategy-based electrochemical reductive carboxylation method according to claim 1, which specifically comprises the following steps:

s1, adding an organic halide or a pseudohalide, a nickel catalyst, a ligand, an alkali and an electrolyte into a cathode chamber of an H-shaped partition electrolytic cell with nonmetal electrodes fixed on two sides under an inert gas atmosphere, and then adding a halogen salt into an anode chamber of the H-shaped partition electrolytic cell;

3. The non-sacrificial anode strategy-based electrochemical reductive carboxylation method according to claim 2, wherein the amount of the nickel catalyst in S1 is 1-20% molar equivalents of the organic halide or pseudohalide; the amount of the ligand is 1-40% molar equivalent of the organohalide or pseudohalide; the amount of the base is 0.1 to 3 times the molar equivalent of the organic halide or pseudohalide; the concentration of the electrolyte is 0.05-0.4M; the addition amount of the halogen salt in the anode chamber is 10-200% of the molar equivalent of the organic halide or the pseudohalide; the addition amount of the reducing agent in the anode chamber is 100-400% of the organic halide or the pseudohalide.

4. The non-sacrificial anode strategy-based electrochemical reductive carboxylation method according to claim 2, wherein the halogen salt in S1 comprises at least one of an inorganic chloride salt, an inorganic bromide salt, an inorganic iodide salt and an organic halogen salt; the organic halide or pseudohalide in the S1 comprises aryl chloride, aryl bromide, aryl iodide, aryl sulfonate, alkyl bromide, alkyl iodide, alkyl sulfonate or alkyl chloride; the nickel catalyst comprises one or two of inorganic nickel salt and organic nickel complex; the ligand comprises at least one of polysubstituted 2, 2' -bipyridyl compounds, polysubstituted phenanthroline compounds and polysubstituted pyridine compounds; the alkali comprises one or two of inorganic alkali and organic alkali; the electrolyte comprises inorganic halogen-containing salt, organic ammonium salt or ionic liquid; the solvent comprises at least one of a pyrrolidone organic solvent, an amide organic solvent, a sulfoxide organic solvent, an imidazolinone organic solvent, a nitrile organic solvent, an alcohol organic solvent, an alkane organic solvent, a substituted alkane organic solvent, an ester organic solvent, a furan organic solvent and water; the reducing agent comprises aromatic hydrocarbon, amine compound, alcohol, phenol or mercaptan.

5. The non-sacrificial anode strategy-based electrochemical reductive carboxylation method according to claim 2 or 4, wherein the reducing agent comprises mono-substituted benzene, poly-substituted benzene, fused ring compound, substituted fused ring compound, alkylamine, di-substituted amine, tri-substituted amine, arylamine, poly-substituted arylamine, alkyl alcohol, alkyl thiol, benzene (sulfur) phenol or poly-substituted benzene (sulfur) phenol.

6. The non-sacrificial anode strategy based electrochemical reductive carboxylation process according to claim 2 or 4, wherein the halogen salt comprises lithium chloride, sodium chloride, lithium bromide, sodium bromide, lithium iodide, sodium iodide, etc., tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetraethylammonium chloride or tetraethylphosphonium chloride; the nickel catalyst comprises at least one of nickel chloride, nickel bromide, nickel iodide, nickel perchlorate hydrate, nickel chloride ethylene glycol dimethyl ether adduct, nickel bromide diethylene glycol dimethyl ether adduct, bis- (1, 5-cyclooctadiene) nickel and nickel acetylacetonate; the base comprises at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, cesium carbonate, potassium phosphate, potassium dihydrogen phosphate, potassium hydrogen phosphate, sodium dihydrogen phosphate, sodium hydrogen phosphate, sodium fluoride, potassium fluoride, cesium fluoride, sodium methoxide, potassium methoxide, sodium ethoxide, lithium tert-butoxide, sodium tert-butoxide, potassium tert-butoxide, 1, 8-diazohetero-bis-spiro [5.4.0] undec-7-ene and 157-triazabicyclo (4.4.0) dec-5-ene; the electrolyte comprises sodium iodide, lithium bromide, lithium chloride, sodium chloride, lithium iodide, lithium perchlorate, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetrabutylammonium tetrafluoroborate, tetrabutylammonium hexafluorophosphate, tetrabutylammonium perchlorate, tetraethylammonium chloride, tetraethylammonium bromide, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium bromide, 1-butyl-3-methylimidazolium iodide, 1-butyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium nitrate, 1-butyl-3-methylimidazolium hydrogen sulfate, lithium iodide, tetrabutylammonium perchlorate, tetrabutylammonium tetrabutyl chloride, tetrabutylammonium tetrafluoroborate, ammonium tetrabutylphosphonium hexafluorophosphate, ammonium tetrafluoroborate, ammonium tetrabutylphosphonium tetrafluoroborate, ammonium tetrabutyl-butyl-3-methylimidazolium bromide, ammonium tetrafluoroborate, phosphonium bromide, and mixtures thereof, At least one of 1-butyl-3-methylimidazole perchlorate, 1-butyl-3-methylimidazole trifluoroacetate, 1-butyl-3-methylimidazole trifluoromethanesulfonate, 1-butyl-3-methylimidazole tetrafluoroborate, 1-butyl-3-methylimidazole hexafluorophosphate, 1-ethyl-3-methylimidazole tetrafluoroborate, 1-hexyl-3-methylimidazole tetrafluoroborate and 1-octyl-3-methylimidazole tetrafluoroborate; the solvent is at least one of N-methyl pyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethyl sulfoxide, 1, 3-dimethyl-2-imidazolidinone, acetonitrile, methanol, dichloromethane, ethyl acetate, tetrahydrofuran and water.

7. The non-sacrificial anode strategy-based electrochemical reductive carboxylation method according to claim 2, wherein the non-metal/inert electrode comprises one or both of a carbon-based material electrode and an inert metal electrode.

8. The non-sacrificial anode strategy-based electrochemical reduction carboxylation method according to claim 2 or 7, wherein the non-metal/inert electrode comprises at least one of a graphite electrode, a glassy carbon electrode, a carbon felt electrode, a carbon paper electrode, a carbon cloth electrode, a platinum electrode, a gold electrode and a niobium electrode.

9. The non-sacrificial anode strategy-based electrochemical reduction carboxylation method according to claim 2, wherein the reaction parameters in S2 are as follows: the reaction constant voltage is 0.5-10V; the reaction time is 0.5-48h, and the reaction temperature is 0-100 ℃.