CN-121991110-A - Method for catalyzing benzoic acid deacidification and boride by using visible light induced ketone

Abstract

The invention relates to the technical field of organic synthesis, and discloses a method for catalyzing benzoic acid deacidification and boriding by using visible light induced ketone. A process for directly decarboxylating and boronizing arylcarboxylic acid includes such steps as reacting arylcarboxylic acid with boron source in the presence of ketone photosensitive agent, oxidant, alkali and solvent under irradiation of visible light to obtain arylboric acid ester. The method adopts the ketone compound as the photosensitizer, reduces the catalysis cost, ensures that the reaction is carried out under the conditions of mild temperature and visible light, has mild conditions and low energy consumption, realizes the direct decarboxylation and the boronation of the benzoic acid substrate, does not need to activate carboxylic acid in advance, has simple and convenient operation, has high efficiency and high speed of a reaction system, has low loading capacity of the ketone photosensitizer and economic boron source consumption, has good compatibility for various functional groups, provides a new way for synthesizing various aryl borate esters efficiently, simply and conveniently and greenly, and can better meet the requirement of organic synthesis on the aryl borate esters.

Inventors

• ZHANG LIANG
• HU PENG

Assignees

• 中山大学

Dates

Publication Date

20260508

Application Date

20260202

Claims (10)

1. 1. A process for the direct decarboxylation boration of an aryl carboxylic acid comprising the steps of: under inert atmosphere, aryl carboxylic acid and boron source react under the existence of ketone photosensitizer, oxidant, alkali and solvent, and then aryl borate is directly obtained.
2. 2. The direct decarboxylation boronation process of claim 1, wherein the molar ratio of aryl carboxylic acid to boron source is 1 (1-3).
3. 3. The method for direct decarboxylation and boronation of aryl carboxylic acid according to claim 2, wherein the ketone photosensitizer is used in an amount of 8mo1% -12mo1% of aryl carboxylic acid, and the molar ratio of the oxidizing agent, base and aryl carboxylic acid is (1.5-3): 2-4): 1.
4. 4. The direct decarboxylation boronation process of claim 1, wherein the aryl carboxylic acid has the structural formula of formula (I): Formula (I); Wherein R 1 is selected from hydrogen, halogen, alkyl, phenyl, alkoxy, acyl, cyano, sulfonamide, or cyclized fused substituents; r 2 is selected from hydrogen, halogen, alkyl, acyl, ester, sulfonyl, benzoyl, or cyclized fused substituents; r 3 is selected from hydrogen, halogen or acyl; r 4 is selected from hydrogen or halogen; R 5 is selected from hydrogen or halogen.
5. 5. The direct decarboxylation boronation process of claim 1, wherein the boron source comprises a bisboronic acid pinacol ester.
6. 6. The direct decarboxylation boronation process of claim 1, wherein the ketone photosensitizer is selected from any one of the following compounds: 。
7. 7. The method for direct decarboxylation and boronation of aryl carboxylic acid according to claim 1, wherein the oxidizing agent is selected from at least one of N-fluoro bis-benzene sulfonamide, iodobenzene acetate, selectFluor II, potassium persulfate, di-t-butyl peroxide, manganese dioxide, iodosobenzene.
8. 8. The method for direct decarboxylation boronation of aryl carboxylic acid according to claim 1, wherein the base is selected from at least one of alkali metal hydroxide, alkali metal carbonate, alkali metal phosphate, alkaline earth metal carbonate, alkaline earth metal fluoride, organic amine compound.
9. 9. The direct decarboxylation boronation process of claim 1, wherein the solvent is selected from at least one of acetonitrile, toluene, dimethyl sulfoxide, tetrahydrofuran, ethyl acetate.
10. 10. The method for direct decarboxylation and boronation of aryl carboxylic acid according to claim 1, wherein the wavelength of visible light is 380-420nm, and the reaction is carried out at room temperature for 5-60min.

Description

Method for catalyzing benzoic acid deacidification and boride by using visible light induced ketone Technical Field The invention relates to the technical field of organic synthesis, in particular to a method for catalyzing benzoic acid deacidification and boriding by using visible light induced ketone. Background Aromatic borate is used as an important organic synthesis intermediate, has wide application in carbon-carbon bond construction reactions such as Suzuki-Miyaura coupling and the like, and is a key building block for constructing a complex aromatic ring system. Aromatic carboxylic acids are considered to be ideal precursors for the preparation of the corresponding borates because of their wide sources, high stability and diverse structures. The traditional arylcarboxylic acid decarboxylation and boronization method mainly relies on transition metal (such as palladium, nickel, iron and the like) catalysis, is carried out under the high-temperature condition, has high energy consumption and limited compatibility to functional groups, and restricts the application of the arylcarboxylic acid decarboxylation and boronization method in complex molecular synthesis. In recent years, photocatalytic strategies have provided new approaches to decarboxylation functionalization under mild conditions. However, the decarboxylation rate of aryl carboxylic acid radicals (about 10 1s-1) is significantly lower than that of alkyl carboxylic acid radicals (about 10 5s-1), resulting in competing side reactions such as hydrogen atom transfer, radical addition, reverse electron transfer, etc. that are prone to occur in the reaction, making photoinduced direct decarboxylation boronation of aryl carboxylic acids still present a significant challenge. Although studies have been made to achieve this conversion by pre-activating carboxylic acids (e.g., to form active esters) or using high energy ultraviolet light excitation, such methods typically rely on expensive photocatalysts (e.g., iridium, ruthenium complexes), excess boron sources, and have long reaction times, complex systems, and inconvenient operations. If Wei et al provide a method for directly decarboxylating and boronizing carboxylic acid compounds under the catalysis of visible light, the reaction is carried out under the condition of air, the method has the characteristics of high step economy and good functional group compatibility, and the difficult problems of decarboxylation of carboxyl free radicals and the boronizing process thereof in dynamic balance are solved. However, the reactions require expensive iridium, cobalt complex photocatalysts, are costly, rely on stoichiometric guanidine additives to activate carboxylic acids and participate in the formation of key intermediates, are severe at (-35 ℃) and extremely long (24 h), limiting their synthesis utility and scale-up potential. Therefore, the method for directly decarboxylating and boronizing the aryl carboxylic acid without pre-activation, high efficiency, low load and low boron source dosage under the condition of visible light is developed, and has important scientific research value and practical application significance. Disclosure of Invention The present invention aims to solve at least one of the above technical problems in the prior art. Therefore, the invention aims to provide a method for catalyzing benzoic acid deacidification and boric acid by using visible light induced ketone. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: the invention aims to provide a direct decarboxylation and boronation method of aryl carboxylic acid, which comprises the following steps: under inert atmosphere, aryl carboxylic acid and boron source react under the existence of ketone photosensitizer, oxidant, alkali and solvent, and then aryl borate is directly obtained. In some embodiments of the invention, the inert atmosphere comprises N 2. In some embodiments of the invention, the molar ratio of aryl carboxylic acid to boron source is 1 (1-3). In some preferred embodiments of the invention, the molar ratio of aryl carboxylic acid to boron source is 1 (1-2). In some embodiments of the invention, the ketone photosensitizer is used in an amount of 8 mole 1% -12 mole 1% of the aryl carboxylic acid, and the molar ratio of the oxidizing agent, base, and aryl carboxylic acid is (1.5-3): 2-4): 1. In some preferred embodiments of the invention, the ketone photosensitizer is used in an amount of 9 mole 1% -11 mole 1% of the aryl carboxylic acid, and the molar ratio of the oxidizing agent, base and aryl carboxylic acid is (1.5-2): 2.5-3.5): 1. In some embodiments of the invention, the ratio of aryl carboxylic acid to solvent is 1mmol (8-12) mL. In some preferred embodiments of the invention, the ratio of aryl carboxylic acid to solvent is 1mmol (9-11) mL. In some embodiments of the invention, the aryl carboxylic acid has a structural formula shown in formula (I): Formul