CN116926619A - Amino acid synthesis method - Google Patents

Amino acid synthesis method Download PDF

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CN116926619A
CN116926619A CN202210375679.7A CN202210375679A CN116926619A CN 116926619 A CN116926619 A CN 116926619A CN 202210375679 A CN202210375679 A CN 202210375679A CN 116926619 A CN116926619 A CN 116926619A
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acid
amino acid
nitrogen
porous carbon
amino
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李光琴
冼家慧
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Sun Yat Sen University
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Sun Yat Sen University
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Priority to PCT/CN2023/087512 priority patent/WO2023198025A1/en
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B15/00—Operating or servicing cells
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
    • C07C227/04—Formation of amino groups in compounds containing carboxyl groups
    • C07C227/06—Formation of amino groups in compounds containing carboxyl groups by addition or substitution reactions, without increasing the number of carbon atoms in the carbon skeleton of the acid
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C227/00—Preparation of compounds containing amino and carboxyl groups bound to the same carbon skeleton
    • C07C227/04—Formation of amino groups in compounds containing carboxyl groups
    • C07C227/06—Formation of amino groups in compounds containing carboxyl groups by addition or substitution reactions, without increasing the number of carbon atoms in the carbon skeleton of the acid
    • C07C227/08—Formation of amino groups in compounds containing carboxyl groups by addition or substitution reactions, without increasing the number of carbon atoms in the carbon skeleton of the acid by reaction of ammonia or amines with acids containing functional groups
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
    • C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
    • C25B11/051—Electrodes formed of electrocatalysts on a substrate or carrier
    • C25B11/054—Electrodes comprising electrocatalysts supported on a carrier
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/01—Products
    • C25B3/07—Oxygen containing compounds
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/01—Products
    • C25B3/09—Nitrogen containing compounds
    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
    • C25B3/00—Electrolytic production of organic compounds
    • C25B3/20—Processes
    • C25B3/25—Reduction

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  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
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  • Metallurgy (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The application belongs to the technical field of amino acid synthesis, and particularly relates to a synthesis method of amino acid. The synthesis method of the application comprises the following steps: under the action of a porous carbon material catalyst, an alpha keto acid compound is used as a carbon source, a nitrogen oxide is used as a nitrogen source, and an organic nitrogen compound is synthesized through electrocatalytic reaction, wherein the organic nitrogen compound comprises one or more of amino acid, organic oxime, organic amine and amide; amino acids in the synthetic methods of the application include essential and non-essential amino acids for the human body. The application provides a method for synthesizing amino acid, which is used for solving the defects of high energy consumption, long time consumption and complex product separation and purification in the existing method for synthesizing amino acid.

Description

Amino acid synthesis method
Technical Field
The application belongs to the technical field of amino acid synthesis, and particularly relates to a synthesis method of amino acid.
Background
Amino acids, which are essential components of proteins, play an important role in life and have many potential uses, such as: animal feed additives, flavoring agents, medicines, cosmetics, etc. Currently, amino acids are mainly produced from sugar or starch as a base material through a microbial fermentation process, which can produce 20 amino acids (α -amino acids) constituting proteins, but some amino acids are still produced with low efficiency. In addition, the fermentation process has the important defects of strict requirements on sterile operation conditions, high energy consumption and long time consumption for microorganism culture, complex product separation and purification process and the like.
Chemical synthesis is a simple and effective method for synthesizing amino acids, the most common method is the Strecker reaction, which is generally carried out by reacting aldehyde or ketone with hydrocyanic acid, cyanide and amine to obtain cyanamide (or alpha-aminonitrile), and hydrolyzing to obtain corresponding alpha-amino acid, wherein primary amine and secondary amine can be used in the reaction except ammonia. The reaction mechanism is that ammonium ions firstly react with carbonyl groups to generate an intermediate compound of imine, and cyanide anions attack carbon of the imine to generate corresponding cyanamide. The method has the advantages of mature and simple process, short reaction time, less waste liquid amount and about 70 percent of yield, but the use of highly toxic cyanide and high environmental protection pressure.
In summary, the microbial fermentation process has the defects of strict requirements on aseptic operation conditions, high microbial culture energy consumption, long time consumption, complex product separation and purification process and the like. The Strecker reaction of chemical synthesis needs to use highly toxic cyanide, and the environmental protection pressure is high.
Disclosure of Invention
In view of the above, the application provides a method for synthesizing amino acid, which is used for solving the defects of high energy consumption, long time consumption and complex product separation and purification in the existing method for synthesizing amino acid.
The application provides a method for synthesizing amino acid, which comprises the following steps:
under the action of a porous carbon material catalyst, an alpha keto acid compound is used as a carbon source, a nitrogen oxide is used as a nitrogen source, and an organic nitrogen compound is synthesized through electrocatalytic reaction.
In another embodiment, the porous carbon material catalyst has a total pore volume of 0.05-5.0cm 3 Per gram, specific surface area greater than 100-4000m 2 /g。
In another embodiment, the alpha keto acids include one or more of pyruvic acid, 4-hydroxyphenylpyruvic acid, 3-hydroxypyruvic acid, 3-thiopyruvic acid, 3-methyl-2-oxobutyric acid, 3-indolopyuvic acid, imidazole-4-pyruvic acid, 2-butanoic acid, 6-amino-2-oxohexanoic acid, 4- (methylthio) -2-oxo-butyric acid, 3-hydroxy-2-oxo-butyric acid, 4-amino-2, 4-dioxobutyric acid, 5-amino-2, 5-dioxopentanoic acid, 5- [ diaminomethylene ] amino ] -2-oxopentanoic acid, 3-methyl-2-oxopentanoic acid, 4-methyl-2-oxopentanoic acid, phenylpyruvic acid, glyoxylic acid, oxaloacetic acid, alpha-ketoglutaric acid, and 2-butanoic acid.
More specifically, the alpha keto acid compound comprises one or more of pyruvic acid, 3-methyl-2-oxobutyric acid, 3-methyl-2-oxopentanoic acid, 4-methyl-2-oxopentanoic acid, phenylpyruvic acid, glyoxylic acid, oxaloacetic acid, alpha-ketoglutaric acid and 2-butanoic acid.
In another embodiment, the nitrogen oxides are selected from NO, NO 2 、、N 2 O、NH 3 、NH 4+ 、NH 2 OH, nitrate nitrogen and nitrite nitrogen.
In another embodiment, the concentration of the alpha keto acid compound is 5mM or more, and the synthesis reaction of the amino acid can be started at the concentration or more.
Specifically, the concentration of the alpha keto acid compound is 0.005-1000M.
In another embodiment, the nitrogen oxides areWhen in gas, the flow velocity of the nitrogen oxide is more than or equal to 10mLmin -1 At this flow rate or more, the synthesis reaction of the amino acid can be started.
Specifically, when the nitrogen oxide is gas, the flow rate of the nitrogen oxide is 0.01-1000L min -1 。
In another embodiment, when the nitrogen oxide is a liquid, the concentration of the nitrogen oxide is 5mM or more, and the synthesis reaction of the amino acid can be started at the concentration or more.
Specifically, when the nitrogen oxide is liquid, the concentration of the nitrogen oxide is 0.005-1000M.
In another embodiment, the electrocatalytic voltage ranges from-0.1 v vs. rhe to-5.0 v vs. rhe.
In particular, when the catalyst, carbon source and nitrogen source are sufficient, the electrocatalytic activity of the synthesis method of the present application can be continued without time limitation.
In another embodiment, the organic nitrogen compound comprises one or more of an amino acid, an organic oxime, an organic amine, and an amide; the amino acid is selected from one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine and pyrrolysine.
The synthesis method of the application mainly comprises amino acid.
The porous carbon material catalyst used in the method for synthesizing amino acid provided by the application can be conventional porous carbon material catalyst sold in the prior art, can be metal-organic framework material, nitrogen-containing metal-organic framework material and other materials, and can also be porous carbon skeleton loaded with hetero atoms or/and multi-metal atoms, and the porous carbon material catalyst is further limited and described below.
In another embodiment, the porous carbon material catalyst comprises a porous carbon skeleton and heteroatoms or/and multiple metal atoms distributed in the porous carbon skeleton, wherein the porous carbon skeleton mainly comprises microporous, mesoporous and macroporous carbon structural materials, the heteroatoms are selected from one or more of N, O, S and P, and the multiple metal atoms are selected from one or more of Al, cu, mn, co, ni, mg, fe, zn, pt, pd, ag, au and Ru.
In another embodiment, the method for preparing the porous carbon material catalyst includes:
calcining the nitrogen-containing metal-organic framework material in a protective atmosphere to obtain a porous carbon material catalyst; wherein the nitrogen-containing metal-organic framework material is selected from one or more of MET-6, ZIF-8, ZIF-67, MOF-74, PPy@MOF, PDA@MOF, HKUST-1, PCN series, MIL series, UIO series and UCM series.
In another embodiment, the method for producing MET-6 comprises:
step 1, mixing soluble zinc salt, an auxiliary agent and an amide compound to obtain a mixture;
step 2, mixing the mixture with 1H-1,2, 3-triazole ligand to obtain MET-6.
In another embodiment, in step 1, the soluble zinc salt is selected from zinc chloride or/and zinc nitrate; the auxiliary agent is selected from one or more of ethanol, water and ammonia water; the amide compound is selected from one or more of N, N-dimethylformamide, N-diethylformamide and N, N-dimethylacetamide.
Specifically, the ammonia water is an aqueous solution containing 25% -28% of ammonia.
Specifically, in the step 2, the mixing time is 20-30 hours. The mixing in step 1 and step 2 is stirring mixing.
Specifically, step 2 further comprises filtering a product obtained by mixing the mixture with 1H-1,2, 3-triazole ligand to obtain a solid product, and washing and drying the solid product to obtain MET-6; the washing adopts ethanol washing, and the drying temperature is 60-90 ℃.
In another embodiment, the method further comprises: mixing a nitrogen-containing metal-organic framework material, a metal salt and a solvent, filtering to obtain a solid, and drying the solid to obtain an M@MOF;
the preparation method of the porous carbon material catalyst specifically comprises the following steps: calcining the M@MOF under a protective atmosphere to obtain a metal atom doped porous carbon material catalyst;
the metal salt is selected from Al 3+ Chloride salts of (C), al 3+ Nitrate of (C), al 3+ Acetate, al of (2) 3+ Sulfate, cu of (C) 2+ Chloride, cu of (C) 2+ Nitrate, cu of (C) 2+ Acetate, cu of (C) 2+ Sulfate, mn of (C) 2+ Chloride salts of (C), mn 2+ Nitrate, mn of (2) 2+ Acetate, mn of (C) 2+ Sulfate, co of (C) 2+ Chloride salt of (Co) 2+ Nitrate, co of (C) 2+ Acetate, co of (C) 2+ Sulfate, ni of (C) 2+ Chloride salt of Ni 2+ Nitrate of (Ni) 2+ Acetate, ni 2+ Sulfate, mg of (2) 2+ Chloride salt, mg of (1) 2+ Nitrate of (1), mg 2+ Acetate, mg of (2) 2+ Sulfate of Fe (2) 2+ Chloride salt of (Fe) 2+ Nitrate of (Fe) 2+ Acetate, fe of (a) 2+ Sulfate of Fe (2) 3+ Chloride salt of (Fe) 3+ Nitrate of (Fe) 3+ Acetate, fe of (a) 3+ Sulfate, zn of (2) 2+ Chloride, zn of (C) 2+ Nitrate, zn of (2) 2+ Acetate, zn of (a) 2+ Sulfate, zn of (2) 2+ Chloride, zn of (C) 2+ Nitrate, zn of (2) 2+ Acetate, zn of (a) 2+ Sulfate, pt of (2) 2+ Chloride salt of (C), pt 2+ Nitrate of (1), pt 2+ Acetate, pt of (2) 2+ Chlorate, pd of (C) 2+ Chloride salt, pd of (C) 2+ Nitrate, pd of (C) 2+ Acetate, pd of (C) 2+ Chlorate, ag of (C) 2+ Chloride, ag of (C) 2+ Sulfate, ag of (2) 2+ Acetate, ag of (2) 2+ Sulfate of (1), au 3+ Chloride salts of (1), au 3+ Sulfate of (1), au 3+ Acetate, au of (C) 3+ Chlorate, ru of 3+ Chloride salts of (Ru) 2+ Sulfate, ru of (C) 3+ Acetate and Ru of (A) 4+ One or more of the chlorates of (a);
the solvent is one or more selected from ethanol, methanol, N-dimethylformamide, chloroform, acetone, distilled water and tetrahydrofuran.
Specifically, mixing a soluble zinc salt, an auxiliary agent and an amide compound to obtain a mixture; mixing the mixture with a 1H-1,2, 3-triazole ligand to obtain MET-6; mixing the MET-6, one or more metal salts and a solvent, filtering to obtain a solid, and drying the solid to obtain M@MOF; calcining the M@MOF under a protective atmosphere to obtain the metal atom doped porous carbon material catalyst.
Specifically, the mixing temperature of the MET-6, the metal salt and the solvent is 60-100 ℃ and the time is 6-10 h.
Specifically, mixing a soluble zinc salt, an auxiliary agent and an amide compound to obtain a mixture; mixing the mixture with a 1H-1,2, 3-triazole ligand to obtain MET-6; calcining the MET-6 in a protective atmosphere to obtain the catalyst for synthesizing the amino acid, wherein the catalyst is a nitrogen atom doped porous carbon material.
Specifically, calcining the Fe@MET-6 precursor nitrogen-containing metal-organic framework under a protective atmosphere to obtain the iron-doped porous carbon material catalyst.
Specifically, calcining the Cu@MET-6 precursor nitrogen-containing metal-organic framework under a protective atmosphere to obtain the copper doped porous carbon material catalyst.
Specifically, the Cu-Fe@MET-6 nitrogenous precursor metal-organic framework is calcined under a protective atmosphere to obtain the copper-iron doped porous carbon material catalyst.
Specifically, calcining the Ni@MET-6 nitrogen-containing precursor metal-organic framework under a protective atmosphere to obtain the nickel-doped porous carbon material catalyst.
Specifically, calcining the Ni-Pt@MET-6 nitrogen-containing precursor metal-organic framework under a protective atmosphere to obtain the nickel-platinum doped porous carbon material catalyst.
Specifically, the Fe-Al@MET-6 nitrogen-containing precursor metal-organic framework is calcined under a protective atmosphere to obtain the Fe-Al doped porous carbon material catalyst.
In another embodiment, the temperature of the calcination is 600 ℃ to 1500 ℃; the calcination time is 1-24 h.
The application applies the principle of the reductive amination reaction of alpha-keto acid, takes the cheap porous nitrogen-doped carbon material catalyst doped with iron atoms as a catalyst, takes nitrogen oxides as a nitrogen source, and performs electrocatalytic reduction to form NH 3 Or NH 2 OH, and the alpha-keto acid are subjected to coupling reaction and then subjected to reductive hydrogenation to form the alpha-amino acid. The application avoids the use of highly toxic cyanide, toxic metal (lead and mercury) and noble metal catalyst, and uses nitrogen oxide as nitrogen source to be coupled and converted with alpha-keto acid to form amino acid.
Drawings
FIG. 1 is a schematic diagram of the synthetic route of amino acids provided by the present application;
FIG. 2 shows the H-NMR results of a valine standard sample provided in example 2 of the present application;
FIG. 3 shows LC-MS results after derivatization of valine standard samples provided in example 2 of the present application;
FIG. 4 shows the H-NMR results of the electrolyte reacted in the cathode chamber for various times according to example 3 of the present application;
FIG. 5 shows LC-MS results for an electrolyte in a cathode chamber provided in example 3 of the present application;
FIG. 6 is a graph showing the H-NMR spectrum of the electrolyte solution and the corresponding peak area integration results at different electrolysis times in the cathode chamber according to example 3 of the present application;
FIG. 7 is a graph showing the results of conversion of a raw material (3-methyl-2-oxobutanoic acid) for producing valine at various electrolysis times in a cathode chamber according to example 3 of the present application;
FIG. 8 is a graph showing the H-NMR spectrum of valine prepared according to the application at different concentrations of 3-methyl-2-oxobutanoic acid and at different flow rates of NO gas, and the corresponding integrated peak areas;
FIG. 9 is a graph showing the H-NMR spectrum of valine prepared at different applied potentials according to example 5 of the present application, and the corresponding integrated peak areas;
FIG. 10 is a H-NMR result of an electrolyte solution in a cathode chamber according to example 6 of the present application;
FIG. 11 is a H-NMR result of an electrolyte solution in a cathode chamber according to example 7 of the present application;
FIG. 12 is the H-NMR results of an electrolyte solution in a cathode chamber provided in example 8 of the application;
FIG. 13 is the LC-MS results of the electrolyte in the cathode chamber provided in example 8 of the present application;
FIG. 14 shows LC-MS results for an electrolyte in a cathode chamber provided in example 9 of the present application;
FIG. 15 is the LC-MS results of the electrolyte in the cathode chamber provided in example 10 of the present application;
FIG. 16 is the H-NMR result of an electrolyte solution in a cathode chamber according to example 11 of the present application;
FIG. 17 is the LC-MS results of the electrolyte in the cathode chamber provided in example 11 of the present application;
FIG. 18 is the H-NMR result of an electrolyte solution in a cathode chamber according to example 12 of the present application;
FIG. 19 is the LC-MS results of the electrolyte in the cathode chamber provided in example 12 of the present application;
FIG. 20 is the LC-MS results of the electrolyte in the cathode chamber provided in example 13 of the present application;
FIG. 21 is the H-NMR result of an electrolyte solution in a cathode chamber according to example 14 of the present application;
FIG. 22 shows LC-MS results for an electrolyte in a cathode chamber provided in example 14 of the present application;
FIG. 23 is a H-NMR result of an electrolyte solution in a cathode chamber according to example 15 of the present application;
FIG. 24 shows LC-MS results for an electrolyte in a cathode chamber provided in example 15 of the present application.
Detailed Description
The application provides a method for synthesizing amino acid, which is used for solving the technical defects of high energy consumption, long time consumption and complex product separation and purification in the method for synthesizing amino acid in the prior art.
All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.
Wherein, the raw materials or reagents used in the following examples are all commercially available or self-made.
Referring to FIG. 1, FIG. 1 is a schematic diagram showing the synthesis route of amino acids according to the present application, nitrogen oxides such as NO are first electrically reduced to form NH 3 Or NH 2 OH, then as a nucleophile, attacks the carbonyl to give an intermediate (imine or oxime), which is subsequently reduced and hydrogenated to form the amino acid. Two reaction pathways: (1) carbonyl compounds and NH 3 Condensation to give, for example, imines, followed by transfer of 2 electrons and addition of 2H by electroreduction + Forming an amino acid; (2) carbonyl compounds and NH 2 OH condensation to give, for example, oximes, followed by electroreduction transfer of 4 electrons and addition of 4H + Amino acids are formed.
Example 1
The present example provides different porous carbon material catalysts, the synthesis process of which is as follows:
1. iron-based material (iron monoatomic material anchored on nitrogen-doped carbon support) porous nitrogen-doped carbon material catalyst:
(1) Synthesis of precursor MET-6: 5.0g of ZnCl 2 Firstly, dissolving in a mixed solution of 50mL of ethanol, 75mL of deionized water, 20mL of ammonia water and 50mLN, N-dimethylformamide, and then magnetically stirring to form a uniform solution; 6.26mL of 1H-1,2, 3-triazole ligand was then added dropwise to the above mixed solution, followed by magnetic stirring at room temperature for 24 hours. Finally, the white product MET-6 was obtained by centrifugation, washing with ethanol and drying at 80 ℃.
(2) Synthesis of iron doped MET-6 precursor (Fe-dopedMET-6): 10mg of iron acetate was dissolved in 50mL of methanol, 2.0g of MET-6 precursor was dispersed in the above-mentioned methanol solution of iron, then stirred at 80℃for 8 hours, and finally the iron-doped MET-6 precursor was obtained as iron-doped MET-6 precursor Fe-doped MET-6 by evaporating the methanol solvent.
(3) Synthesis of iron monoatomic material anchored on nitrogen doped carbon support (Fe SA/NC): placing the Fe-doped MET-6 sample obtained in the step (2) on a ceramic tile, calcining for 3 hours at 950 ℃ in an argon atmosphere in a tube furnace, cooling to room temperature to obtain the black porous carbon material catalyst doped with iron atoms, wherein the black porous carbon material catalyst is an iron single-atom material anchored on a nitrogen-doped carbon carrier and is marked as an Fe SA/NC catalyst.
2. Nitrogen doped porous carbon material catalyst:
(1) Synthesis of precursor MET-6: 5.0g of ZnCl 2 Firstly, dissolving in a mixed solution of 50mL of ethanol, 75mL of deionized water, 20mL of ammonia water and 50mLN, N-dimethylformamide, and then magnetically stirring to form a uniform solution; 6.26mL of 1H-1,2, 3-triazole ligand was then added dropwise to the above mixed solution, followed by magnetic stirring at room temperature for 24 hours. Finally, the white product MET-6 was obtained by centrifugation, washing with ethanol and drying at 80 ℃.
(2) Synthesis of (NC) on nitrogen doped porous carbon skeleton: and (3) placing the MET-6 sample obtained in the step (1) on a ceramic tile, calcining for 3 hours at 950 ℃ in an argon atmosphere in a tube furnace, and cooling to room temperature to obtain a black nitrogen-doped porous carbon material catalyst, which is named as NC catalyst.
Example 2
The embodiment of the application is used for carrying out H-NMR (nuclear magnetic resonance hydrogen spectrum) and LC-MS (high performance liquid chromatography-mass spectrometry) tests on valine standard samples, and carrying out qualitative and quantitative analysis on valine so as to confirm the formation of valine. Specifically, in the H-NMR spectrum, the H atom on alpha-C in valine is taken as the judgment basis. In LC-MS, phenylisothiocyanate (PITC) was used as a derivatizing reagent, which reacted with the N-terminal residue in the amino acid under alkaline conditions of triethylamine to form a phenylcarbamoyl derivative, which was detectable by an ultraviolet detector in liquid chromatography at a wavelength of 254nm to confirm the formation of the corresponding amino acid.
The H-NMR spectrum of the valine standard sample solution is shown in FIG. 2, wherein the H atom at alpha-C in valine (i.e. at a) is taken as a judgment basis, H at a is split into two peaks, and the corresponding chemical shifts (abscissa) are 3.85ppm and 3.84ppm. The ratio of the peak areas of the hydrogen atoms at a, b and c was 1:1:5.99 (about 1:1:6), which corresponds to the number of H at the position corresponding to valine.
In LC-MS, valine was subjected to PITC derivatization to give a valine-derivatized product having an exact molecular weight of 252.33. Under the bombardment of electrospray ionization (ESI) negative ion mode, a negative ion peak (M-1 peak) with M/z of 251.0 appears on a mass spectrum in LC-MS (liquid chromatography-mass spectrometry) as shown in figure 3, and the PITC derivatization method is proved to be suitable for detecting amino acid.
Example 3
The embodiment of the application provides a method for synthesizing amino acid, which comprises the following steps:
the reaction for preparing amino acid of the present examples was carried out in a sealed three-electrode H-type electrolytic cell. Valine was synthesized by electrocatalytic reaction with the Fe SA/NC catalyst of example 1, using 3-methyl-2-oxobutanoic acid as the carbon source and NO gas as the nitrogen source.
First, 1.0mg of the Fe SA/NC catalyst of example 1 was uniformly supported on a catalyst having an area of 1X 1cm 2 The glassy carbon electrode is used as a working electrode; a saturated silver/silver chloride electrode is used as a reference electrode; the two electrodes are placed in the cathode chamber of an H-cell. The platinum sheet is used as a counter electrode and is placed in the anode chamber of the H-type electrolytic cell. 30mL of an electrolyte (containing 0.1M HCl and 20mM 3-methyl-2-oxobutanoic acid) was added to the cathode chamber, and 30mL of a 0.1M HCl solution was added to the anode chamber as an electrolyte. Before electrocatalytic treatment, high purity argon is first introduced into the sealed cathode electrolytic chamber for 10 min to replace the oxygen and air in the solution and the upper part of the electrolytic cell with inert argon, NO gas is then introduced for 10 min to saturate the solution, and the solution is maintained in a quality control flowmeter for 20mL min -1 Continuously introducing NO gas. In the electrocatalytic process, electrolysis is carried out by adopting a constant voltage mode, the voltage is set to be-0.6V vs. RHE, and after 4 hours, 5 hours and 6 hours of electrolysis respectively, electrolyte in a cathode chamber at different electrolysis times is respectively collected for product identification (4 hours of products, 5 hours of products and 6 hours of products respectively). The synthesized amino acids were characterized and quantified by nuclear magnetic resonance hydrogen spectroscopy (H-NMR) and high performance liquid chromatography-mass spectrometry (LC-MS). In H-NMR, taking a spectrogram of H atoms on alpha-C in amino acid as a judgment basis; in LC-MS, this example uses Phenylisothiocyanate (PITC) as a derivatizing agent, which reacts with the N-terminal residue of the amino acid under basic conditions of triethylamine to form a phenylsulfamoyl derivative, which derivative is at a wavelength of 254nmCan be detected by ultraviolet detector in liquid chromatograph.
In the electrocatalytic synthesis of amino acids, the voltage was set constant at-0.6 v vs. rhe, and after 4 hours, 5 hours and 6 hours of electrolysis, the electrolytes in the cathode chamber were collected for product identification. Through detection by H-NMR and LC-MS (FIGS. 4 and 5, the abscissa of FIG. 4 is f1 (ppm)), it was found that corresponding peaks appear at a, b and c in H-NMR, consistent with the chemical shift of valine standard, confirming successful valine synthesis. At the same time, H atom on valine alpha-C (i.e. at a) is split into double peaks, corresponding to chemical shifts of 3.85ppm and 3.84ppm, which are consistent with the structure; and the intensity of the double peak thereof was gradually increased with the increase of the electrolysis time, which suggests that the valine production was gradually increased. In LC-MS, there was a negative ion peak (M-1 peak) having M/z of 251.0, which was a negative ion peak of valine-derived products, confirming the formation of valine, which was mutually confirmed with the H-NMR results. Meanwhile, there is still a raw material substance (3-methyl-2-oxobutanoic acid) for preparing valine by electrocatalytic reductive amination.
According to the results of the above-mentioned H-NMR test under different electrolysis times and the peak area ratio of the corresponding peak to the internal standard DMSO, as shown in FIG. 6, the conversion rate of the starting material (3-methyl-2-oxobutanoic acid) for valine production under different electrolysis times was calculated. As shown in FIG. 7, the conversion of the starting material (3-methyl-2-oxobutanoic acid) for valine production was increased with increasing potential and reacted at-0.6V vs. RHE potential for 6 hours to 73.49%.
Example 4
According to the embodiment of the present application, valine is produced by the method of embodiment 3, comprising the steps of:
the process for producing valine according to example 3 is carried out with the difference that 20mM of 3-methyl-2-oxobutanoic acid, 30mM of 3-methyl-2-oxobutanoic acid and a flow rate of 20mL min are used -1 、30mL min -1 The rest of the parameters and steps were identical to those of example 3, with NO gas as carbon source and nitrogen source, respectively, and electrolysis was carried out at-0.6 v vs. rhe potential for 4 hours and 6 hours. The electrolyte in the cathode chamber was then collected for H-NMR analysis (see FIG. 8).
Example 5
According to the embodiment of the present application, valine is produced by the method of embodiment 3, comprising the steps of:
the method for producing valine of this example was conducted with reference to example 3, except that different potentials (-0.6 vvs.rhe and-0.8 vvs.rhe) were applied to electrocatalytically synthesize valine, and electrocatalytic reaction was conducted at reaction times of 4 hours and 6 hours; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The results of the qualitative and quantitative detection by H-NMR are shown in FIG. 9 (the abscissa of FIG. 9 is f1 (ppm)).
Example 6
The embodiment of the application provides a method for synthesizing amino acid, which comprises the following steps:
the reaction for preparing amino acid of the present examples was carried out in a sealed three-electrode H-type electrolytic cell. Under the action of the Fe SA/NC catalyst of example 1, pyruvic acid is used as a carbon source, and 500mM KNO is used 3 Alanine was synthesized by electrocatalytic synthesis as a nitrogen source.
First, 1.0mg of the Fe SA/NC catalyst of example 1 was uniformly supported on a catalyst having an area of 1X 1cm 2 The glassy carbon electrode is used as a working electrode; a saturated silver/silver chloride electrode is used as a reference electrode; the two electrodes are placed in the cathode chamber of an H-cell. The platinum sheet is used as a counter electrode and is placed in the anode chamber of the H-type electrolytic cell. 30mL of electrolyte (containing 0.1M HCl and 20mM pyruvic acid followed by 500mM KNO) was added to the cathode chamber 3 ) While 30ml of 0.1m HCl solution was added as an electrolyte in the anode chamber. Before electrocatalytic treatment, high purity argon is used to ventilate the sealed cathode electrolytic chamber for 10 min, and the oxygen and air in the solution and the upper part of the electrolytic cell are replaced by inert argon. In the electrocatalytic process, electrolysis is carried out by adopting a constant voltage mode, the voltage is set to be-0.6V vs. RHE, and after the electrolysis is carried out for 6 hours, electrolyte in a cathode chamber is collected for product identification. Qualitative analysis was performed by nuclear magnetic resonance hydrogen spectroscopy (H-NMR). In H-NMR, the results are shown in FIG. 10 (FIG. 10, abscissa of FIG. 10, f1 (ppm)) based on the spectrum of the H atom on α -C in the amino acid, and it is found from the results of H-NMR that alanine can be successfully synthesized.
Example 7
The embodiment of the application provides a method for synthesizing amino acid, which comprises the following steps:
the reaction for preparing amino acid of the present examples was carried out in a sealed three-electrode H-type electrolytic cell. Under the action of the Fe SA/NC catalyst of example 1, pyruvic acid is used as a carbon source, and 500mM KNO is used 2 Alanine was synthesized by electrocatalytic synthesis as a nitrogen source.
First, 1.0mg of NC catalyst of example 1 was uniformly supported on a catalyst having an area of 1X 1cm 2 The glassy carbon electrode is used as a working electrode; a saturated silver/silver chloride electrode is used as a reference electrode; the two electrodes are placed in the cathode chamber of an H-cell. The platinum sheet is used as a counter electrode and is placed in the anode chamber of the H-type electrolytic cell. 30mL of electrolyte (containing 0.1M HCl and 20mM pyruvic acid followed by 500mM KNO) was added to the cathode chamber 2 ) While 30ml of 0.1m HCl solution was added as an electrolyte in the anode chamber. Before electrocatalytic treatment, high purity argon is used to ventilate the sealed cathode electrolytic chamber for 10 min, and the oxygen and air in the solution and the upper part of the electrolytic cell are replaced by inert argon. In the electrocatalytic process, electrolysis is carried out by adopting a constant voltage mode, the voltage is set to be-0.6V vs. RHE, and after the electrolysis is carried out for 6 hours, electrolyte in a cathode chamber is collected for product identification. Qualitative analysis was performed by nuclear magnetic resonance hydrogen spectroscopy (H-NMR). In H-NMR, based on the spectrum of the H atom on α -C in the amino acid, as shown in FIG. 11 (the abscissa of FIG. 11 is f1 (ppm)), it was found from the results of H-NMR that valine was successfully synthesized.
Example 8
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for producing valine is described with reference to example 3, except that 4-methyl-2-oxopentanoic acid is substituted for 3-methyl-2-oxobutanoic acid of example 3, and electrocatalytic reaction is carried out at-0.7 v vs. rhe potential for 2 hours; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively by nuclear magnetic resonance hydrogen spectroscopy (H-NMR) and high performance liquid chromatography-mass spectrometry (LC-MS), and leucine was synthesized by electrocatalytic synthesis in this example, and as shown in FIG. 12 (FIG. 12, abscissa of FIG. 12, f1 (ppm)) and FIG. 13, leucine was successfully synthesized as seen from the results of H-NMR.
Example 9
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for producing valine is described with reference to example 3, except that 3-methyl-2-oxopentanoic acid is substituted for 3-methyl-2-oxobutanoic acid of example 3 and the electrocatalytic reaction is carried out at a potential of-0.6 v vs. rhe for 2 hours; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acids were qualitatively synthesized by high performance liquid chromatography-mass spectrometry (LC-MS), and isoleucine was synthesized by electrocatalytic synthesis in this example, and the results are shown in fig. 14, and it is seen from the results of LC-MS that isoleucine was successfully synthesized.
Example 10
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for preparing valine is described with reference to example 3, except that phenylpyruvate is substituted for 3-methyl-2-oxobutanoic acid of example 3 and electrocatalytic is carried out at a potential of-0.6 v vs. rhe; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively by high performance liquid chromatography-mass spectrometry (LC-MS), and phenylalanine was synthesized by electrocatalytic synthesis in this example, and as shown in fig. 15, it was found from the LC-MS results that phenylalanine was successfully synthesized.
Example 11
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for producing valine is described with reference to example 3, except that pyruvic acid is substituted for 3-methyl-2-oxobutanoic acid of example 3 and the electrocatalytic reaction is carried out at a potential of-0.8 v vs. rhe for 2 hours; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively by nuclear magnetic resonance hydrogen spectroscopy (H-NMR) and high performance liquid chromatography-mass spectrometry (LC-MS), and the result of the electrocatalytic synthesis of alanine in this example is shown in FIG. 16 (FIG. 16, abscissa f1 (ppm)) and FIG. 17, and it was found that alanine was successfully synthesized by the results of H-NMR and LC-MS.
Example 12
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for producing valine is described with reference to example 3, except that glyoxylate is substituted for 3-methyl-2-oxobutanoic acid of example 3 and electrocatalytic reactions are carried out at-0.6 v vs. rhe potentials for 2 hours, respectively; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively by nuclear magnetic resonance hydrogen spectroscopy (H-NMR) and high performance liquid chromatography-mass spectrometry (LC-MS), and glycine was synthesized by electrocatalytic synthesis in this example, and as shown in FIG. 18 (FIG. 18, abscissa f1 (ppm)) and FIG. 19, glycine was successfully synthesized as seen from the results of LC-MS.
Example 13
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for producing valine is described with reference to example 3, except that α -ketoglutarate is substituted for 3-methyl-2-oxobutanoic acid of example 3 and electrocatalytic reaction is carried out at-0.8 v vs. rhe potential for 2 hours, respectively; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively by high performance liquid chromatography-mass spectrometry (LC-MS), and glutamic acid was synthesized by electrocatalytic synthesis in this example, and the results are shown in fig. 20, and it can be seen from the results of LC-MS that glutamic acid was successfully synthesized.
Example 14
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for preparing valine is described with reference to example 3, except that oxaloacetate is substituted for the 3-methyl-2-oxobutanoic acid of example 3 and electrocatalytic reactions are carried out at-0.7 v vs. rhe potentials, respectively; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively by nuclear magnetic resonance hydrogen spectroscopy (H-NMR) and high performance liquid chromatography-mass spectrometry (LC-MS), and aspartic acid was synthesized by electrocatalytic reaction in this example, and as shown in FIG. 21 (FIG. 21, abscissa of FIG. 21, f1 (ppm)) and FIG. 22, aspartic acid was successfully synthesized as seen from the results of H-NMR and LC-MS.
Example 15
The amino acid was prepared according to the method of example 3, comprising the steps of:
this example the process for producing valine is conducted with reference to example 3, except that 2-butanoic acid is substituted for 3-methyl-2-oxobutanoic acid of example 3, and electrocatalytic reactions are carried out at-0.7V vs. RHE potentials for 2 hours, respectively; the remaining parameters and steps are consistent with example 3, and the electrolyte in the cathode chamber is collected for product identification. The amino acid synthesized was qualitatively synthesized by nuclear magnetic resonance hydrogen spectroscopy (H-NMR) and high performance liquid chromatography-mass spectrometry (LC-MS), and the results of the electrocatalytic synthesis of aminobutyric acid in this example are shown in FIG. 23 (FIG. 23, abscissa of F1 (ppm)) and FIG. 24, and it was found that aminobutyric acid could be successfully synthesized from the results of H-NMR and LC-MS.
In summary, the results of the present examples demonstrate that oxides of nitrogen are used as the nitrogen source for electrocatalytic reduction to form NH 3 Or NH 2 OH is taken as nucleophilic reagent to attack carbonyl in alpha-keto acid, and then reduced and hydrogenated to form amino acid, the synthesis method of the application uses cheap porous carbon material catalyst doped with hetero atoms, such as iron, copper, nitrogen and the like, and can avoid using noble metal and toxic metal catalysts to obtain amino acid, therefore, the method can utilize electric energy and water as energy and hydrogen energy respectively, and clean energy is used for electrocatalytic conversion of nitrogen-containing oxides in waste gas and waste water to synthesize amino acid.
The foregoing is merely a preferred embodiment of the present application and it should be noted that modifications and adaptations to those skilled in the art may be made without departing from the principles of the present application, which are intended to be comprehended within the scope of the present application.

Claims (10)

1. A method for synthesizing amino acid, comprising the steps of:
under the action of a porous carbon material catalyst, an alpha keto acid compound is used as a carbon source, a nitrogen oxide is used as a nitrogen source, and an organic nitrogen compound is synthesized through electrocatalytic reaction.
2. The method of synthesis according to claim 1, wherein the porous carbon material catalyst has a total pore volume of 0.05-5.0cm 3 Per gram, specific surface area greater than 100-4000m 2 /g。
3. The synthetic method of claim 1, wherein the alpha keto acid compound comprises one or more of pyruvic acid, 4-hydroxyphenylpyruvic acid, 3-hydroxypyruvic acid, 3-thiopyruvic acid, 3-methyl-2-oxobutyric acid, 3-indolopyuvic acid, imidazole-4-pyruvic acid, 2-butanoic acid, 6-amino-2-oxohexanoic acid, 4- (methylthio) -2-oxo-butyric acid, 3-hydroxy-2-oxo-butyric acid, 4-amino-2, 4-dioxobutyric acid, 5-amino-2, 5-dioxopentanoic acid, 5- [ diaminomethylene ] amino ] -2-oxopentanoic acid, 3-methyl-2-oxopentanoic acid, 4-methyl-2-oxopentanoic acid, phenylpyruvic acid, glyoxylic acid, oxaloacetic acid, alpha-ketoglutaric acid, and 2-butanoic acid.
4. The method of synthesis according to claim 1, wherein the nitrogen oxides are selected from the group consisting of NO, NO 2 、NO 2 - 、NO 3 - 、N 2 O、NH 3 、NH 4 + 、NH 2 One or more of OH, nitrate nitrogen, and nitrite nitrogen.
5. The method according to claim 1, wherein the concentration of the alpha keto acid compound is 5mM or more.
6. The method according to claim 1, wherein when the nitrogen oxide is a gas, the flow rate of the nitrogen oxide is highIs equal to or less than 10m Lmin -1 。
7. The method according to claim 1, wherein when the nitrogen oxide is a liquid, the concentration of the nitrogen oxide is 5mM or more.
8. The method of synthesis according to claim 1, wherein the electrocatalytic voltage ranges from-0.1 v vs. rhe to-5 v vs. rhe.
9. The synthetic method of claim 1 wherein the organic nitrogen compound comprises one or more of an amino acid, an organic oxime, an organic amine, and an amide;
the amino acid is one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine and pyrrolysine.
10. The method of synthesis according to claim 1, wherein the porous carbon material catalyst comprises a porous carbon skeleton and heteroatoms or/and multi-metal atoms distributed in the porous carbon skeleton, the porous carbon skeleton mainly comprising microporous, mesoporous and macroporous carbon structural materials, the heteroatoms being selected from one or more of N, O, S and P, the multi-metal atoms being selected from one or more of Al, cu, mn, co, ni, mg, fe, zn, pt, pd, ag, au and Ru.
CN202210375679.7A 2022-04-11 2022-04-11 Amino acid synthesis method Pending CN116926619A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117225336A (en) * 2023-11-13 2023-12-15 东华理工大学南昌校区 Amino acid synthesis equipment and method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117225336A (en) * 2023-11-13 2023-12-15 东华理工大学南昌校区 Amino acid synthesis equipment and method

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