CHALLENGES IN SCHIFF BASE FUNCTIONAL-GROUP SYNTHESIS: A COMPARATIVE AND SPECTROSCOPIC REVIEW

Abstract: Schiff bases (imines, R–CH=N–R′) are fundamental in organic synthesis, coordination chemistry, catalysis and functional materials. Despite their straight forward formation via condensation between primary amines and carbonyl compounds, challenges arise in their synthesis, particularly in terms of purity and yield. Issues such as equilibrium limitations, water sensitivity, steric hindrance and product instability often hinder the process. Additionally, the growing use of solvent-free, microwave-assisted and mechanochemical routes introduces greener alternatives but also presents specific constraints. This review discusses key synthetic challenges, compares traditional solvent-based methods with newer green alternatives and summarizes essential FT-IR and NMR spectroscopic features critical for Schiff-base identification. Recommendations for best practices and future research directions are presented.