CN-121652072-B - Alternating magnetic field assisted Fe3Method for synthesizing 2-keto acid by N-catalyzed oxidation of 2-hydroxy acid

Abstract

The invention belongs to the field of industrial catalysis, in particular to a method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid to oxidize by Fe 3 N with the assistance of an alternating magnetic field, which is shown in the formula 1 ) Mixing 2-hydroxy acid, oxidant and Fe 3 N, and catalytic oxidizing under the assistance of alternating magnetic field to obtain the product of formula 2% ) 2-Keto acid of (2-keto acid). The invention innovatively discovers that the alternating magnetic field is used for assisting Fe 3 N to catalyze 2-hydroxy acid to oxidize, 2-keto acid can be circularly synthesized with high selectivity and high stability under mild conditions, and thus, the invention can be beneficial to the industrialized amplified production of 2-keto acid.

Inventors

• RUAN WENJIE
• DENG LIU
• ZHAO SENFENG

Assignees

• 中南大学

Dates

Publication Date

20260508

Application Date

20260209

Claims (7)

1. 1. A method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid with Fe 3 N under the assistance of an alternating magnetic field is characterized in that 2-hydroxy acid of a formula 1, an oxidant and Fe 3 N are mixed and catalyzed and oxidized under the assistance of the alternating magnetic field to prepare 2-keto acid of the formula 2; 1 (1) 2, 2 In the formula 1, R is C 1 ~C 6 alkyl, phenyl, substituted alkyl or substituted phenyl, wherein the substituent in the substituted alkyl or substituted phenyl comprises at least one of amino, alkoxy, hydroxy, nitro or halogen; Fe 3 N is obtained by ammoniating and roasting an iron source in an ammonia-containing atmosphere at a temperature of 500-800 ℃; The iron source comprises an iron simple substance; The alternating magnetic field strength is 5-35A/cm, and the frequency is 50-500 kHz; the oxidant is an oxygen-containing atmosphere.
2. 2. The method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid to oxidize by Fe 3 N with the aid of alternating magnetic field as set forth in claim 1, wherein Fe 3 N is a nanoparticle with D50 of 50-500 nm and the saturation magnetization is not less than 100 emu/g.
3. 3. The method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid with Fe 3 N with the assistance of alternating magnetic field as set forth in claim 1, wherein the ammonia gas in the ammonia-containing atmosphere has a volume content of 50% or more vol%.
4. 4. The method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid to oxidize by Fe 3 N with the assistance of an alternating magnetic field according to claim 1, wherein the temperature of ammonification and calcination is 600-700 ℃; the ammoniation roasting time is 0.5-5 h.
5. 5. The method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid to oxidize Fe 3 N with the aid of alternating magnetic field according to claim 1, wherein the molar ratio of 2-hydroxy acid of formula 1 to Fe 3 N is 1:0.02-0.12.
6. 6. The method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid with Fe 3 N with the aid of alternating magnetic field as claimed in claim 1, wherein the temperature of the catalytic oxidation reaction stage is 15-70 ℃.
7. 7. The method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid to oxidize by Fe 3 N with the aid of alternating magnetic field according to claim 1, wherein Fe 3 N is recycled.

Description

Method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid to oxidize through Fe 3 N under assistance of alternating magnetic field Technical Field The invention belongs to the field of industrial compound catalytic preparation, and particularly relates to the technical field of 2-keto acid synthesis by oxidizing 2-hydroxy acid. Background 2-Keto acids such as typical pyruvic acid are an important platform compound and are widely used in the pharmaceutical, food, cosmetic and chemical industries. Methods for industrially producing pyruvic acid mainly include chemical synthesis methods, biological fermentation methods and enzyme catalysis methods. For example, patent document publication No. CN110603321A discloses a pyruvate carboxylase and DNA encoding the pyruvate carboxylase, a plasmid comprising the DNA, a microorganism and use thereof. Patent document publication No. CN106544285A discloses a method for synthesizing pyruvic acid by strengthening Torulopsis glabrata. Patent document publication No. CN118667893a discloses a method for synthesizing pyruvic acid using CO 2, and a pyruvic acid synthesis route is obtained that includes a first reaction module that converts CO 2 into formaldehyde, a second reaction module that converts formaldehyde into dihydroxyacetone, and a third reaction module that converts dihydroxyacetone into pyruvic acid. In addition, the prior art also reports that a scheme for preparing pyruvic acid by lactic acid oxidation is disclosed in patent document with publication number CN109053414A, for example, a method for preparing pyruvic acid by ultrasonic intensified oxidation of lactic acid comprises the following steps of (1) weighing disodium hydrogen phosphate, sodium dihydrogen phosphate and sodium bromide, dissolving in water, stirring to prepare a solution A for standby, (2) weighing lactic acid and sodium hydroxide, dissolving in water, preparing a sodium lactate aqueous solution B for standby, (3) mixing the solution A and the solution B, stirring and cooling to 10-15 ℃, 4) stirring and ultrasonic wave, maintaining 10-15 ℃ for 30 minutes, dropwise adding sodium hypochlorite, after dropwise adding, reacting at a temperature of less than 20 ℃, adding hydrochloric acid to the reaction liquid, adjusting pH, adding dichloromethane, extracting pyruvic acid, and (7) desolventizing the extraction liquid to obtain pyruvic acid. In summary, although some preparation methods of keto acid are reported in the prior art, the chemical method often uses strong oxidants, has severe conditions and large environmental pollution, the biological method has the problems of long period, high cost, difficult product separation and the like, and the enzyme principle is limited by the cost, stability and recycling of the enzyme. Therefore, the development of a heterogeneous catalyst which is efficient, stable and recyclable, realizes the efficient conversion from lactic acid to pyruvic acid under mild conditions, and has important industrial value. Disclosure of Invention Aiming at the problems of unsatisfactory reactivity, selectivity, cycling catalytic stability and the like of the existing method for synthesizing the 2-keto acid by oxidizing the 2-hydroxy acid, the invention aims to provide a method for synthesizing the 2-keto acid by catalyzing the 2-hydroxy acid by Fe 3 N with the assistance of an alternating magnetic field, and aims to improve the reactivity, the selectivity and the cycling stability of the 2-keto acid by oxidizing the 2-hydroxy acid based on mild conditions. Aiming at the problems existing in the existing industrial catalytic synthesis of 2-keto acid, the invention provides the following improvement scheme: A method for synthesizing 2-keto acid by catalyzing 2-hydroxy acid with Fe 3 N is carried out by mixing 2-hydroxy acid in formula 1, oxidant and Fe 3 N, and catalyzing and oxidizing under assistance of alternating magnetic field to obtain 2-keto acid in formula 2; 1 (1) 2, 2 In the formula 1, R is C 1~C6 alkyl, phenyl, substituted alkyl or substituted phenyl, wherein the substituent in the substituted alkyl or substituted phenyl comprises at least one of amino, alkoxy, hydroxy, nitro or halogen. The invention innovatively discovers that the alternating magnetic field is used for assisting Fe 3 N to catalyze 2-hydroxy acid to oxidize, 2-keto acid can be circularly synthesized with high selectivity and high stability under mild conditions, and thus, the invention can be beneficial to the industrialized amplified production of 2-keto acid. In the invention, fe 3 N and an alternating magnetic field are combined, so that the synergy can be realized, the activation and conversion of the hydroxyalkyl C-H bond in the formula 1 can be promoted, and the effective conversion from the formula 1 to the formula 2 can be realized under mild conditions. In the invention, fe 3 N is a nanoparticle with D50 of 50-500 nm, preferably 80-320 nm, and the saturation magnetization is not lower