A Novel Method for the Synthesis of Newfangled Asymmetric Schiff Bases from amino Acids under Ultrasonic Conditions and in Aqueous Medium

OpenAlex İngilizce

Chiral Schiff bases were obtained at high yields via a novel technique. Aryl aldehydes and chiral α‐amino acids were treated (1) in the presence of H3PO4 in ethanol at 80°C for 24 h, and (2) in the presence of K2CO3 under ultrasonic conditions in an aqueous ethanol medium within 5 min with yields reaching up to 96%. The results showed that the presented methodology under ultrasonic conditions was effective, practical, and eco‐friendly compared to that using an acidic medium. The corresponding asymmetric Schiff bases were synthesized for the first time, and were characterized by 1H and 13C nuclear magnetic resonance and infrared spectroscopy and high‐resolution mass spectrometry.