Overview of the mechanism of action of 4-formylphenylboronic acid
Phenylboronic acid was synthesized in 1880, but it was not until 1954 that Kuivila et al. first reported the phenomenon that phenylboronic acid could be combined with sugar molecules, and concluded that boronic acid and sugar-formed methoxypyridine form a cyclic ester. In 1959, Edward and Lorand elucidated the tetrahedral configuration of boric acid anion in alkaline aqueous solution, and reported for the first time the results of quantitative research on the interaction between phenylboronic acid and sugar. They believed that 4-tolueneboronic acid interacts with 1,2- or 1,3-di Alcohols form five- and six-membered cyclic esters in non-aqueous or alkaline aqueous solutions, and rigid diols form more stable cyclic esters than simple cyclic diol sugars. This selectivity holds true for all monoboronic acids. , and are not limited to phenylboronic acid. However, it is not until the past decade that the boronic acid receptor recognition system has been extensively studied and applied to the molecular recognition of sugars. Among the reported boronic acid receptor recognition systems, the research work of Shinka group is relatively systematic.
Since organoboronic acid compounds were first synthesized in 1860, due to their special atomic configuration, stable and environmentally friendly properties, they have been widely used in organic synthesis, carbohydrate and ion recognition, and Biomedical and other fields. 4-Formylphenylboronic acid is a type of organic boric acid compound that can be used to identify and detect the presence of various sugars in organisms and determine their concentration.
Mechanism of action of 4-formylphenylboronic acid Mechanism of action
Although boronic acid-containing dyes have been discovered long ago, it was not until 1994 that Sandanayake and Shinkai reported the first sugar acceptor molecule 2A based on color change due to the interaction between 4-formylphenylboronic acid and a tertiary amine. , the adjacent amines form a pH environment around the boric acid molecules that is conducive to the interaction between boric acid and sugar. When 4-formylphenylboronic acid interacts with sugar molecules to form a complex, electrons are directly transferred to the adjacent amines, causing charge transfer of the chromophore Shift of absorption bands. However, after binding to sugar molecules, the absorption band generally shifts slightly, which seriously hinders the development of this type of receptor molecules. If the azoaromatic ring is substituted with an electron-donating or electron-withdrawing group (such as methoxy or nitro), the electronic properties of the chromophore will be greatly improved. James has carried out innovative work in this regard, designing and synthesizing Compound 3A was obtained, and the tertiary amine in 2A was replaced with a secondary amine. After the chromophore was combined with sugar, the maximum absorption peak was blue-shifted by 55 nm. If a sensing system with large color changes can be established, it can be developed into a sugar test paper similar to pH test paper, which can be used directly to measure sugar in the blood. Certain diseases can be diagnosed without the use of specific instruments. Therefore, this type of sugar receptor molecules have good application prospects.
Preparation method of action mechanism of 4-formylphenylboronic acid
Methanol is used as raw material. It first enters the vaporizer and is heated and vaporized into steam. After superheating, it enters the dehydrogenation reactor for catalytic dehydrogenation. The reaction conditions are temperature 150~350℃ and pressure 0~0.2MPa. The catalyst contains a variety of Oxide composite catalyst. The heat required for the dehydrogenation reaction can be supplied by the circulating heat carrier heating system provided by the heating furnace. After cooling, the reaction product enters the separation and refining system tricyclohexylphosphine fluoroborate, which is generally carried out in a distillation tower. The unconverted methanol is separated and returned to the vaporizer for recycling. The hydrogen-containing tail gas can be sent to the PSA-H2 hydrogen extraction unit to recover pure hydrogen. The refined methyl formate with a content of greater than or equal to 97% is sent to the amination reactor for processing with anhydrous methylamine. Amination reaction.
The conditions for amination reaction are temperature 0~90℃ and pressure 0~1.5MPa. The optimal operating conditions are temperature 20~60℃ and pressure 0.1~0.6MPa. It can also be carried out under normal pressure. The ratio of raw materials is methyl formate:methylamine=1.02~1.15:1. The selectivity of the amination reaction is greater than 99%. The amination reaction product enters the separation system, usually in a distillation tower. A small amount of excess amination reaction product is returned to the amination reactor for recycling, and crude 4-formylphenylboronic acid is obtained for further rectification, and finally the purity is greater than 99.5%. Refined 4-formylphenylboronic acid product.
 Synthesis of new aromatic boronic acid derivatives and research on their recognition of sugar molecules, Huang Zhiyu, Guangxi Normal University
Liu Jinghong, Zheng Peng. A preparation method of 4-formylphenylboronic acid, 2014.