Influence of ortho group in rhodamine B hydrazide based Schiff base for selective recognition of Cu and Fe ions: A mechanistic approach by DFT and colorimetric studies.

Herein we have implemented a computational approach in designing sensor molecules for the selective recognition of Cu and Fe ions. Seven rhodamine B hydrazide-based Schiff base derivatives were designed and analysed their chemosensing properties against Cu and Fe ions in ethanol solution theoretically. The theoretical calculations revealed that the selective recognition of Cu and Fe ions takes place via spirolactam ring-opening and there is a pivotal role of ortho substituents and N-heteroatoms. The two best chemosensors were synthesised and used for the detection of Cu and Fe ions by colorimetric methods.