Greener protocol for one pot synthesis of coumarin styryl dyes

A new method for synthesizing novel coumarin styryl dyes based on 2-(1-(7-(diethylamino)-2-oxo-2H-chromen-3-yl)ethylidene)malononitrile is proposed by an eco-friendly approach in a single pot using a deep eutectic solvent (DES). The DES is cheaper and biodegradable and serves the dual role of catalyst as well as solvent. The approach provides an environment-friendly pathway, simple procedure, mild conditions, and excellent yields of novel styryl dyes. Reaction using DES requires lesser reaction time than conventional method. It is easy to separate product after reaction. DES can be recycled several times without losing its activity. These novel dyes show good thermal stability and brilliant fluorescence. They can find potential applications in fluorescent chemosensors and laser technology etc. (C) 2012 Elsevier Ltd. All rights reserved.