Boronic acids have garnered significant attention in the field of organic chemistry due to their versatile reactivity and broad applicability. Among these, 3-acrylamidophenylboronic acid (AAPBA) stands out for its unique properties, making it a valuable compound for various applications ranging from materials science to biomedical research.
AAPBA is a versatile chemical compound featuring both acrylamide and phenylboronic acid functional groups, making it valuable in various fields of research and industry. The presence of the acrylamide moiety allows it to participate in polymerization reactions, forming hydrogels and copolymers with unique properties. Meanwhile, the phenylboronic acid group provides the ability to interact with diols, sugars, and other molecules through reversible covalent bonding, making it useful in the development of sensors, drug delivery systems, and responsive materials. This dual functionality of AAPBA makes it a key component in designing innovative materials and applications across biotechnology, medicine, and materials science.
In this protocol, EDCI is used as a condensation agent to synthesize AAPBA through a condensation reaction between APBA and AA. The reaction is relatively mild and easy to control.
Fig. 1 Synthesis of AAPBA.
Reagents and Chemicals
- 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI)
- 3-Aminophenylboronic acid hemisulfate (APBA)
- Acrylic acid (AA)
- Sodium hydroxide (NaOH), analytical grade.
- Ether, analytical grade.
- Deionized water.
Synthesis Procedure of AAPBA
First, 6 mmol (0.43 g) of AA was dissolved in 4 mL of deionized water, and the pH of the aqueous solution of AA was adjusted to 4.8 with NaOH aqueous solution and then cooled down to 4 ℃ in the refrigerator freezer. Then 6 mmol (1.12 g) of APBA was dissolved in 20 mL of deionized water, and the pH of the aqueous solution of APBA was adjusted to 4.8 with NaOH aqueous solution as well and put into a 50 mL three-necked flask with nitrogen gas. The aqueous APBA solution was cooled down to 4 ℃ with an ice-water bath, 6 mmol (1.15 g) of EDCI was added, and then the cooled down aqueous AA solution was added, and the reaction was carried out at 4 ℃ for 1 h. After the ice-water bath was removed, the reaction temperature was raised to room temperature, and the reaction was continued for 12 h. The reaction was filtered, and the reaction products were extracted with 20 mL of ether, and the procedure was repeated four times. The ether was removed by vacuum drying at room temperature to obtain a white solid powder. The white solid powder was dissolved in 20 mL of water, recrystallized at low temperature, filtered, and dried under vacuum at room temperature to obtain the final white crystalline product.
