Hydrazine bridged coumarin-pyrimidine conjugate as a highly selective and sensitive Zn2 + sensor: Spectroscopic unraveling of sensing mechanism with practical application

Abstract We report the synthesis and Zn 2 + sensing of a novel coumarin-hydrazine conjugate 3-{1-[(4, 6-Dimethyl-pyrimidin-2-yl)-hydrazono]-ethyl}-chromen-2-one ( 3 ). Compound 3 can act as a neat fluorescent Zn 2 + sensor by an increment in fluorescence intensity along with an appreciable red shift. Fluorescence enhancement is caused by complexation through cis-trans isomerization process in the presence of Zn 2 + ion. The practical utility of 3 was demonstrated by successful test kit experiment to detect Zn 2 + in water under UV-light.