CN109503531B - Preparation method of benzofuran compound - Google Patents

Preparation method of benzofuran compound Download PDF

Info

Publication number
CN109503531B
CN109503531B CN201811302274.0A CN201811302274A CN109503531B CN 109503531 B CN109503531 B CN 109503531B CN 201811302274 A CN201811302274 A CN 201811302274A CN 109503531 B CN109503531 B CN 109503531B
Authority
CN
China
Prior art keywords
benzofuran
reaction
furan
acetic acid
compound
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201811302274.0A
Other languages
Chinese (zh)
Other versions
CN109503531A (en
Inventor
康世民
许祖铭
邱浩
刘锦柱
徐勇军
孙成华
李杰泰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gansu Jiujian Junde Pharmaceutical Technology Co.,Ltd.
Shenzhen Litong Information Technology Co ltd
Original Assignee
Dongguan University of Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dongguan University of Technology filed Critical Dongguan University of Technology
Priority to CN201811302274.0A priority Critical patent/CN109503531B/en
Publication of CN109503531A publication Critical patent/CN109503531A/en
Application granted granted Critical
Publication of CN109503531B publication Critical patent/CN109503531B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
    • C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
    • C07D307/78—Benzo [b] furans; Hydrogenated benzo [b] furans
    • C07D307/79—Benzo [b] furans; Hydrogenated benzo [b] furans with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
    • C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
    • C07D307/78—Benzo [b] furans; Hydrogenated benzo [b] furans
    • C07D307/82—Benzo [b] furans; Hydrogenated benzo [b] furans with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to carbon atoms of the hetero ring

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Furan Compounds (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

The invention relates to a preparation method of benzofuran compounds. The preparation method comprises the following steps: putting the furan compound, acetic acid and a Lewis acid catalyst into a reaction container, reacting for 0.5-24 h at the temperature of 80-160 ℃, and separating and purifying to obtain the benzofuran compound. The preparation method provided by the invention directly obtains the benzofuran compound through one-step reaction at a mild reaction temperature (80-160 ℃) by taking the furan compound as a reaction raw material, taking an acetic acid aqueous solution as a solvent and taking Lewis acid as a catalyst. The preparation method provided by the invention can be used for synthesizing the benzofuran compound with the corresponding structure and functional group based on the structure and functional group of the furan compound as a raw material, and has the advantages of simple raw material components and convenient process operation; wherein, in the process of synthesizing benzofuran by furan, the selectivity of the obtained benzofuran reaches up to 99 percent, and the method has industrial application prospect.

Description

Preparation method of benzofuran compound
Technical Field
The invention belongs to the field of benzofuran synthesis, and particularly relates to a preparation method of benzofuran compounds.
Background
The benzo-ceramoman compound has strong biological activity, including antifungal activity, anti-inflammatory activity, antitumor activity, antioxidant activity, anti-rheumatoid activity, calcium polymerization inhibition activity, anti-platelet activity, plant development stimulation and the like. The benzofuran compound can also be applied to the field of medicines so as to improve the physiological activity of the original compound. The biological activity and the application of the benzo-cerate-like pyran compounds in the field of medicine attract people's close attention. At present, the synthesis route of benzofuran compounds is long, and the reaction conditions are severe. Benzofuran is the core structure of benzofuran compounds, and is also the simplest benzofuran compound. Even the artificial synthesis of benzofuran requires many reaction raw materials and multiple catalytic reactions. For example, phenoxyalkanones are first prepared by reacting a 2-haloketone with a phenol, and then are used in an acid-catalyzed dehydration process to prepare benzofurans (Bull. chem. Soc. Jpn.1971,44,749). The raw material 2-halogenated ketone in the method is not easy to obtain and has high price, and the yield and the selectivity of the benzofuran in the reaction process are low. Benzofuran can also be prepared by starting from salicylaldehyde and substituted bromoacetate, but this method requires three steps of reaction, is complicated to operate, and has a high process cost (j. org. chem.1996,61,6498). Therefore, it is of great significance to develop a reaction technique with simple operation and few process steps, and to synthesize the benzopyran compound with conventional low molecular chemicals.
Disclosure of Invention
The invention aims to overcome the defects and shortcomings of long route, severe reaction conditions, various types of required initial raw materials and difficult obtainment of the conventional benzofuran compound synthesis method, and develop a preparation method of the benzofuran compound. The preparation method provided by the invention can be used for synthesizing benzofuran compounds with corresponding structures and functional groups based on the structures and functional groups of furan compounds as raw materials. The raw material provided by the invention is simple in components and convenient in process operation; wherein, in the process of synthesizing benzofuran by furan, the selectivity of the obtained benzofuran reaches up to 99 percent, and the method has industrial application prospect.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of benzofuran compounds comprises the following steps: putting the furan compound, acetic acid and a Lewis acid catalyst into a reaction container, reacting for 0.5-24 h at the temperature of 80-160 ℃, and separating and purifying to obtain the benzofuran compound.
According to the preparation method provided by the invention, a furan compound is used as a unique reaction raw material, acetic acid is used as a solvent, Lewis acid is used as a catalyst, and the benzofuran compound is directly obtained through one-step reaction at a mild reaction temperature (80-160 ℃); the preparation method provided by the invention has the advantages of simple raw material components, convenient process operation, high selectivity and industrial application prospect.
It should be understood that the benzofuran compound with the corresponding structure and functional group can be synthesized by taking the furan compound as a raw material, and selecting a single furan compound as a raw material, or selecting a plurality of furan compounds as raw materials according to the structure and functional group of the furan compound.
Preferably, the furan compound is represented by the formulas (I) and (II):
Figure BDA0001852693900000021
wherein R is1～R8Independently selected from hydrogen, alkyl or thiol groups.
Preferably, when R is1And R2When the hydrogen is contained, the benzofuran compound shown as the formula (III) is obtained; when R is3And R4When the hydrogen is contained, the benzofuran compound shown as the formula (IV) is obtained;
Figure BDA0001852693900000022
preferably, the alkyl group is C1～4An alkyl group.
Preferably, the thiol group is-SH or-SR, and R is C1～2An alkyl group.
Preferably, the lewis acid catalyst is one or more of aluminum chloride, boron trifluoride, ferric chloride or antimony pentafluoride.
Preferably, the furan compound is one or two of furan, 2-methylfuran and 2, 5-dimethylfuran.
Furan, 2-methylfuran and 2, 5-dimethylfuran are all obtainable from biomass as a starting material. For example, catalytic hydrolysis of Biomass to pentoses followed by decarbonylation of furfural formed by dehydration of the pentoses produces furan (Biomass 1984,4, 263). Furan, 2-methylfuran and 2, 5-dimethylfuran are all renewable resources from the standpoint of starting with biomass. In addition, furan is widely present in pine tar and has become a bulk chemical with wide application.
More preferably, the furan-based compound is furan.
In the process of synthesizing benzofuran by furan, the selectivity can reach 99 percent, and the method has industrial application prospect.
Preferably, the lewis acid catalyst is one or more of aluminum chloride, boron trifluoride, ferric chloride or antimony pentafluoride.
Preferably, the reaction temperature is 100-150 ℃.
Preferably, the reaction time is 1-12 h.
Preferably, the mass concentration of the Lewis acid catalyst in the reaction container is 1-8%.
The catalyst can realize better catalytic action under the mass concentration, and can reduce the cost of the catalyst.
Preferably, the preparation method further comprises the step of adding water to obtain an acetic acid aqueous solution before reaction, wherein the volume ratio of acetic acid to water is 1: 0-1: 5.
The addition of a proper amount of water is beneficial to improving the solubility of the Lewis acid catalyst in a reaction system, so that the reaction is a homogeneous catalytic reaction, and the reaction is promoted.
Preferably, the mass concentration of the furan compound in the acetic acid water solution is 1-100 g/L.
More preferably, the mass concentration of the furan compound in the acetic acid aqueous solution is 10 g/L.
Preferably, the separation and purification mode is rectification.
Compared with the prior art, the invention has the following beneficial effects:
the preparation method provided by the invention directly obtains the benzofuran compound through one-step reaction at a mild reaction temperature (80-160 ℃) by taking the furan compound as a reaction raw material, taking an acetic acid aqueous solution as a solvent and taking Lewis acid as a catalyst. The preparation method provided by the invention can be used for synthesizing the benzofuran compound with the corresponding structure and functional group based on the structure and functional group of the furan compound as a raw material, and has the advantages of simple raw material components and convenient process operation; wherein, in the process of synthesizing benzofuran by furan, the selectivity of the obtained benzofuran reaches up to 99 percent, and the method has industrial application prospect.
Drawings
FIG. 1 is a schematic diagram of the preparation of benzofuran compounds from furans of example 1;
FIG. 2 is a GC-FID internal standard method quantitative analysis chart of the reaction product in example 1;
FIG. 3 is a GC-MS analysis spectrum of the reaction product obtained in example 15;
FIG. 4 is a GC-MS analysis spectrum of the reaction product obtained in example 16;
FIG. 5 is a GC analysis spectrum of a reaction product obtained in example 17;
FIG. 6 is a GC analysis spectrum of a reaction product obtained in example 18;
FIG. 7 is a GC-MS analysis spectrum of a reaction product obtained in example 19;
FIG. 8 is a GC-MS analysis spectrum of a reaction product obtained in example 20;
FIG. 9 is a GC analysis spectrum of a reaction product obtained in example 21.
Detailed Description
The invention is further illustrated by the following examples. These examples are intended to illustrate the invention and are not intended to limit the scope of the invention. Experimental procedures without specific conditions noted in the examples below, generally according to conditions conventional in the art or as suggested by the manufacturer; the raw materials, reagents and the like used are, unless otherwise specified, those commercially available from the conventional markets and the like. Any insubstantial changes and substitutions made by those skilled in the art based on the present invention are intended to be covered by the claims.
Example 1
A method for synthesizing benzofuran from furan comprises the following steps (reaction formula is shown in figure 1):
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.02g of furan and 0.1g of aluminum chloride catalyst were added to the reaction tube.
The reaction tube was placed at 140 ℃ for 1 hour and cooled to obtain benzofuran. The reaction product was dissolved in dichloromethane after adding ethylbenzene as an internal standard, and quantitative analysis of furan and benzofuran in dichloromethane was performed by GC-FID (see fig. 2). The conversion rate of furan is 30.5%, the yield of benzofuran is 25.8%, and the selectivity of benzofuran is as high as 99.1%. And recovering the solvent and the benzofuran product by adopting a rectification method, distilling at 100 ℃ to obtain an acetic acid aqueous solution as a solvent, and further distilling at 170-175 ℃ to obtain benzofuran.
Example 2
A method for synthesizing benzofuran from furan, comprising:
preparing an acetic acid aqueous solution with the volume ratio of acetic acid to water being 3:1, adding 2mL of the acetic acid aqueous solution into a 10mL reaction tube, and adding 0.02g of furan and 0.04g of aluminum chloride catalyst 3 into the reaction tube.
The reaction tube was placed at 140 ℃ for 6 hours and cooled to give benzofuran. Adding the reaction product into an internal standard substance ethylbenzene, dissolving the reaction product in dichloromethane, and quantitatively analyzing furan and benzofuran in the dichloromethane by adopting GC-FID. The furan conversion rate is 35.3%, the benzofuran yield is 29.8%, and the selectivity of benzofuran is as high as 97.3%. And recovering the solvent and the benzofuran product by adopting a rectification method.
Example 3
A method for synthesizing benzofuran from furan, comprising:
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.02g of furan and 0.1g of aluminum chloride catalyst were added to the reaction tube.
The reaction tube was placed at 155 ℃ for 1 hour and cooled to give benzofuran. The furan conversion rate is 36.7%, the benzofuran yield is 27.2%, and the selectivity of benzofuran is as high as 85.5%. And recovering the solvent and the benzofuran product by adopting a rectification method.
Example 4
A method for synthesizing benzofuran from furan, comprising:
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 4:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.01g of furan and 0.1g of aluminum chloride catalyst were added to the reaction tube.
The reaction tube was placed at 140 ℃ for 2 hours to obtain benzofuran. After cooling, the solvent and the benzofuran product are recovered by rectification.
Example 5
A method for synthesizing benzofuran from furan, comprising:
(1) an aqueous acetic acid solution having a volume ratio of acetic acid to water of 5:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.02g of furan and 0.1g of aluminum chloride catalyst were added to the reaction tube.
(2) The reaction tube is placed at 160 ℃ for reaction for 0.5 hour, and after cooling, the solvent and the benzofuran product are recovered by adopting a rectification method.
Example 6
A method for synthesizing benzofuran from furan, comprising:
(1) an aqueous acetic acid solution having a volume ratio of acetic acid to water of 1:3 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.04g of furan and 0.1g of aluminum chloride catalyst were put into the reaction tube.
(2) The reaction tube is placed at 120 ℃ for reaction for 6 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 7
A method for synthesizing benzofuran from furan, comprising:
(1) an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.1g of furan and 0.06g of aluminum chloride catalyst were added to the reaction tube.
(2) The reaction tube is placed at 100 ℃ for reaction for 12 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 8
A method for synthesizing benzofuran from furan, comprising:
(1) an aqueous acetic acid solution having a volume ratio of acetic acid to water of 1:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.15g of furan and 0.12g of aluminum chloride catalyst were added to the reaction tube.
(2) The reaction tube is placed at 80 ℃ for reaction for 24 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 9
A method for synthesizing benzofuran from furan, comprising:
(1) an aqueous acetic acid solution having a volume ratio of acetic acid to water of 1:5 was prepared, 2mL of the aqueous acetic acid solution was taken and added to a 10mL reaction tube, and 0.2g of furan and 0.16g of aluminum chloride catalyst were further added to the reaction tube.
(2) The reaction tube is placed at 90 ℃ for reaction for 24 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 10
A method for synthesizing benzofuran from furan, comprising:
(1) 2mL of this acetic acid was added to a 10mL reaction tube, to which was added 0.2g of furan and 0.08g of aluminum chloride catalyst.
(2) The reaction tube is placed at 140 ℃ for reaction for 3 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 11
A method for synthesizing benzofuran from furan, comprising:
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.06g of furan and 0.1g of iron chloride catalyst were added to the reaction tube.
The reaction tube is placed at 140 ℃ for reaction for 1 hour, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 12
A method for synthesizing benzofuran from furan, comprising:
(1) preparing an acetic acid aqueous solution with the volume ratio of acetic acid to water being 2:1, adding 2mL of the acetic acid aqueous solution into a 10mL reaction tube, and adding 0.02g of furan and 0.1g of antimony pentafluoride catalyst into the reaction tube.
(2) The reaction tube is placed at 130 ℃ for reaction for 6 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 13
A method for synthesizing benzofuran from furan, comprising:
(1) an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was charged into a 10mL reaction tube, and 0.02g of furan and 0.1g of boron trifluoride catalyst were added to the reaction tube.
(2) The reaction tube is placed at 120 ℃ for reaction for 10 hours, and the solvent and the benzofuran product are recovered by adopting a rectification method after cooling.
Example 14
A method for synthesizing benzofuran from furan, comprising:
2ml of acetic acid was charged into a 10ml reaction tube, to which were further added 0.02g of furan and 0.1g of aluminum chloride catalyst.
The reaction tube was placed at 140 ℃ for 3 hours to obtain benzofuran. Adding the reaction product into an internal standard substance ethylbenzene, dissolving the reaction product in dichloromethane, and quantitatively analyzing furan and benzofuran in the dichloromethane by adopting GC-FID. The conversion rate of furan is 100%, the yield of benzofuran is 12%, and the selectivity of benzofuran is as high as 12%. After cooling, the solvent and the benzofuran product are recovered by adopting a rectification method.
Example 15
A method for synthesizing 2, 7-dimethyl benzofuran by reacting 2-methyl furan (reaction formula is shown in figure 1) comprises the following steps:
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was taken and added to a 10mL reaction tube, and 0.02g of 2-methylfuran and 0.1g of an aluminum chloride catalyst were added to the reaction tube.
The reaction tube was placed at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the product was analyzed by GC-MS (see FIG. 3), with 2, 7-dimethylbenzofuran as the main reaction product. 2, 7-Dimethylbenzofuran in dichloromethane was quantitatively analyzed by GC-FID. The conversion of 2-methylfuran was 26.6% and the yield of 2, 7-dimethylbenzofuran was 15.8%. The solvent and the product 2, 7-dimethyl benzofuran can be separated and recovered by a rectification method.
Example 16
A method for synthesizing 2, 7-diethylbenzofuran by reacting 2-ethylfuran (the reaction formula is shown in figure 1) comprises the following steps:
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was taken and added to a 10mL reaction tube, and 0.02g of 2-ethylfuran and 0.1g of an aluminum chloride catalyst were added to the reaction tube.
The reaction tube was placed at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the product was analyzed by GC-MS (see FIG. 4), with 2, 7-diethylbenzofuran as the main reaction product. Quantitative analysis by GC-FID showed 20.1% conversion of 2-ethylfuran and 12.8% yield of 2, 7-diethylbenzofuran. The solvent and the product can be separated and recovered by a rectification method.
Example 17
A method for synthesizing 2-methylbenzofuran, 4-methylbenzofuran and 7-methylbenzofuran by reacting furan with 2-methylbenzofuran (the reaction formula is shown in figure 1), wherein the method comprises the following steps:
an aqueous acetic acid solution having a volume ratio of acetic acid to water of 3:1 was prepared, 2mL of the aqueous acetic acid solution was put into a 10mL reaction tube, and 0.01g of furan, 0.01g of 2-methylfuran and 0.1g of aluminum chloride catalyst were put into the reaction tube.
The reaction tube was allowed to react at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the products were analyzed by GC (see FIG. 5) for 2-methylbenzofuran, 4-methylbenzofuran and 7-methylbenzofuran, and further, benzofuran (obtained by the reaction of furan itself) and 2, 7-dimethylbenzofuran (obtained by the reaction of 2-methylbenzofuran itself). Quantitative analysis by GC-FID showed 2.7% yield of 2-methylbenzofuran, 1.9% yield of 4-methylbenzofuran and 2.8% yield of 7-methylbenzofuran. The acetic acid aqueous solution and the main product can be separated and recovered by a rectification method.
Example 18
A method for synthesizing 4, 7-dimethyl benzofuran by reacting furan with 2, 5-dimethyl furan (reaction formula is shown in figure 1) comprises the following steps:
preparing an acetic acid aqueous solution with the volume ratio of acetic acid to water being 3:1, adding 2mL of the acetic acid aqueous solution into a 10mL reaction tube, and adding 0.01g of furan, 0.01g of 2, 5-dimethylfuran and 0.1g of aluminum chloride catalyst into the reaction tube.
The reaction tube was allowed to react at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the product was analyzed by GC-MS (see FIG. 6), and 4, 7-dimethylbenzofuran, benzofuran (obtained by the reaction of furan itself) and 2, 5-hexanedione (obtained by the reaction of 2, 5-dimethylfuran itself) and the like were contained in the product. The acetic acid aqueous solution and the main product can be separated and recovered by a rectification method.
Example 19
A method for synthesizing 2-ethylbenzofuran and 7-ethylbenzofuran by reacting furan with 2-ethylfuran (reaction formula is shown in figure 1), which comprises the following steps:
preparing an acetic acid aqueous solution with the volume ratio of acetic acid to water being 3:1, adding 2mL of the acetic acid aqueous solution into a 10mL reaction tube, and adding 0.01g of furan, 0.01g of 2-ethylfuran and 0.1g of aluminum chloride catalyst into the reaction tube.
The reaction tube was allowed to react at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the product was analyzed by GC (see FIG. 7) for 2-ethylbenzofuran and, in addition to 7-ethylbenzofuran, benzofuran (obtained by the reaction of furan itself) and 2, 7-diethylbenzofuran (obtained by the reaction of 2-ethylfuran itself). The acetic acid aqueous solution and the main product can be separated and recovered by a rectification method.
Example 20
A method for synthesizing 2-methyl-3-thiol benzofuran by reacting furan with 2-methyl-3-furanthiol (formula shown in figure 1) comprises the following steps:
preparing an acetic acid aqueous solution with the volume ratio of acetic acid to water being 3:1, adding 2mL of the acetic acid aqueous solution into a 10mL reaction tube, and adding 0.01g of furan, 0.01g of 2-methyl-3-furanthiol and 0.1g of aluminum chloride catalyst into the reaction tube.
The reaction tube was placed at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the product was analyzed by GC (see FIG. 8), in which 2-methyl-3 thiol benzofuran and benzofuran (obtained by reacting furan itself) were present. The acetic acid aqueous solution and the main product can be separated and recovered by a rectification method.
Example 21
A method for synthesizing 2,4, 7-trimethylbenzofuran by reacting 2-methylfuran with 2, 5-dimethylfuran (reaction formula is shown in figure 1), which comprises the following steps:
preparing an acetic acid aqueous solution with the volume ratio of acetic acid to water being 3:1, adding 2mL of the acetic acid aqueous solution into a 10mL reaction tube, and adding 0.01g of 2-methylfuran, 0.01g of 2, 5-dimethylfuran and 0.1g of aluminum chloride catalyst into the reaction tube.
The reaction tube was placed at 140 ℃ for 3 hours, the reaction product was dissolved in methylene chloride, and the product was analyzed by GC-MS (see FIG. 9), in which 2,4, 7-trimethylbenzofuran and the reaction product of 2-methylfuran with 2, 5-dimethylfuran itself were present. The acetic acid aqueous solution and the main reaction product can be separated and recovered by a rectification method.
It will be appreciated by those of ordinary skill in the art that the examples provided herein are intended to assist the reader in understanding the principles of the invention and are to be construed as being without limitation to such specifically recited examples and embodiments. Those skilled in the art can make various other specific changes and combinations based on the teachings of the present invention without departing from the spirit of the invention, and these changes and combinations are within the scope of the invention.

Claims (5)

1. A preparation method of benzofuran compounds is characterized by comprising the following steps: putting a furan compound, an acetic acid aqueous solution and a Lewis acid catalyst into a reaction container, reacting for 0.5-24 h at the temperature of 80-160 ℃, and separating and purifying to obtain a benzofuran compound; the Lewis acid catalyst is aluminum chloride;
the furan compound has a structure shown in a formula (I) and a formula (II):
Figure FDA0002834835590000011
R1～R8independently selected from hydrogen, alkyl, thiol or-SR, R is C1～2An alkyl group;
and R is1And R2Is hydrogen, or R3And R4Is hydrogen, or R5And R6Is hydrogen, or R7And R8Is hydrogen;
when R is1And R2When the hydrogen is contained, the benzofuran compound shown as the formula (III) is obtained; when R is3And R4When the hydrogen is contained, the benzofuran compound shown as the formula (IV) is obtained;
Figure FDA0002834835590000012
the preparation method also comprises the step of adding water to obtain an acetic acid aqueous solution before reaction, wherein the volume ratio of the acetic acid to the water is 3: 1.
2. The method according to claim 1, wherein the alkyl group is C1～4An alkyl group.
3. The method according to claim 1, wherein the temperature of the reaction is 100-150 ℃; the reaction time is 1-12 h.
4. The method according to claim 1, wherein the mass concentration of the Lewis acid catalyst in the reaction vessel is 1-8%.
5. The method according to claim 1, wherein the mass concentration of the furan compound in the acetic acid aqueous solution is 1-100 g/L.
CN201811302274.0A 2018-11-02 2018-11-02 Preparation method of benzofuran compound Active CN109503531B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811302274.0A CN109503531B (en) 2018-11-02 2018-11-02 Preparation method of benzofuran compound

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811302274.0A CN109503531B (en) 2018-11-02 2018-11-02 Preparation method of benzofuran compound

Publications (2)

Publication Number Publication Date
CN109503531A CN109503531A (en) 2019-03-22
CN109503531B true CN109503531B (en) 2021-06-01

Family

ID=65747491

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201811302274.0A Active CN109503531B (en) 2018-11-02 2018-11-02 Preparation method of benzofuran compound

Country Status (1)

Country Link
CN (1) CN109503531B (en)

Also Published As

Publication number Publication date
CN109503531A (en) 2019-03-22

Similar Documents

Publication Publication Date Title
US8455668B2 (en) Method for preparing hydroxymethylfurfural
WO2013146085A1 (en) Method for producing 5-hydroxymethyl furfural
CN112608296A (en) Method for synthesizing brazilanin natural product Brazilane
EP3221301A1 (en) Acid-catalyzed acylation of 5-(hydroxylmethyl)-furfural reduction products
CN108610311B (en) Method for preparing 5-hydroxymethylfurfural by using boehmite to catalyze glucose at low temperature
Wu et al. HClO 4–SiO 2-catalyzed synthesis of 12-aryl-12 H-benzo [i][1, 3] dioxolo [4, 5-b] xanthene-6, 11-diones and 10-aryl-6, 7, 8, 10-tetrahydro-7, 7-dimethyl-9 H-[1, 3] dioxolo [4, 5-b] xanthen-9-ones
EP2495239B1 (en) Method for preparing 4-hydroxymethylfurfural
CN109503531B (en) Preparation method of benzofuran compound
CN114149314B (en) Synthesis method of VK2
CN109942459B (en) Method for synthesizing 3-difluoromethyl-3-acrylonitrile compounds
CN107641067B (en) Alpha-bromination method of o-diketone
CN109535120A (en) The preparation method of 7- substitution -3,4,4,7- tetrahydro cyclobutane and cumarin -5- ketone
CN104744406A (en) Method for preparing epoxy caryophyllene from heavy turpentine oil and separating longifolene
CN111170837B (en) Synthesis method of methyl ketone compound
CN113773182A (en) Method for synthesizing 6, 8-dichloro caprylic acid ester
CN102321054B (en) Preparation method of tetrahydrofuran-3-ketone compound
CN102964212B (en) Synthetic method of 1,2,4-butanetriol
CN108069832B (en) Preparation method of 2,3,5, 6-tetrafluorophenol
CN111574446A (en) Triarylmethane compound and synthesis method thereof
CN101402649A (en) Fatty acid aluminium isopropoxide, preparation method and application thereof
CN105037114A (en) Preparation method of 2-(2-methoxyethoxy)acetaldehyde diethyl acetal
CN111517985B (en) Preparation method of 4- [ (1R) -1-amino-2-hydroxyethyl ] -3-fluoro-benzonitrile
CN109369357B (en) Method for preparing symmetrical diaryl ketone by catalytic oxidation carbonylation
Sabitha et al. Study of conventional versus microwave-assisted reactions of 3, 4-epoxyalcohols by CeCl3· 7H2O: Synthesis of tetrahydrofurans and 1-chloro-3-substituted-2-propanols
CN112321599B (en) Synthesis method of drug intermediate 7-oxo-2-azaspiro [3.5] nonane

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
TR01 Transfer of patent right
TR01 Transfer of patent right

Effective date of registration: 20240117

Address after: Factory Building B5, Block 19, Lanzhou Western Pharmaceutical Valley Industrial Park, No. 1139 Songshan Road North Section, Lanzhou New Area, Lanzhou City, Gansu Province, 730000

Patentee after: Gansu Jiujian Junde Pharmaceutical Technology Co.,Ltd.

Address before: 509 Kangrui Times Square, Keyuan Business Building, 39 Huarong Road, Gaofeng Community, Dalang Street, Longhua District, Shenzhen, Guangdong Province, 518000

Patentee before: Shenzhen Litong Information Technology Co.,Ltd.

Effective date of registration: 20240117

Address after: 509 Kangrui Times Square, Keyuan Business Building, 39 Huarong Road, Gaofeng Community, Dalang Street, Longhua District, Shenzhen, Guangdong Province, 518000

Patentee after: Shenzhen Litong Information Technology Co.,Ltd.

Address before: 523000, 1, University Road, Songshan science and Technology Industrial Park, Guangdong, Dongguan

Patentee before: DONGGUAN University OF TECHNOLOGY