Oxazolines are a class of heterocyclic organic compounds that are widely used as building blocks in the synthesis of pharmaceuticals, agrochemicals, and materials. However, during the synthesis process, impurities can be introduced that may affect the quality and safety of the final product. Oxazolines impurities can be formed due to incomplete reactions, side reactions, or degradation of the starting materials. These impurities can have different chemical structures and physical properties, and their identification and quantification are critical for ensuring the purity and efficacy of the final product.