Versatile Synthesis, Photophysical, Solvatochromic, and Metal Ion Sensing Properties of Naphthyl‐Cored Stilbenes

Abstract The present work describes a facile and efficient method for the synthesis of naphthyl‐cored donor‐π‐acceptor aromatic stilbenes under ultrasonic irradiation. The synthetic method has been presented via ring transformation of α‐pyranones with ( E )‐4‐phenylbut‐3‐en‐2‐one using KOH in DMF, carried out at room temperature in ultrasonic bath. The α‐pyranones serve as versatile parent precursors in the ring transformation strategy, enabling the efficient construction of naphthyl‐cored donor–π–acceptor stilbenes. The targeted products were obtained in good to excellent yields and exhibited remarkable fluorescence properties, highlighting their potential in photophysical applications. The fluorescent lifetime of synthesized compounds was determined. The lone pair on nitrogen, electron withdrawing nitrile group and styryl moiety are in suitable conjugation within the molecule sustaining the aromaticity in the entire molecules and thereby, producing to shift the absorption toward longer wavelength. Moreover, the quantum yield was found in between 10.9% to 31.9%. The synthesized molecules were studied for photophysical properties including absorbance, emissions and solute‐solvent interaction in various solvents of different polarity. Metal ion sensing studies revealed that the synthesized naphthyl‐cored stilbene derivatives 11a and 11d displayed selective sensing for trivalent ions (Fe 3+ , Cr 3+ , Al 3+ ).In addition fluorescent lifetime was also determined using time‐correlated single‐photon counting (TCSPC). Moreover, the naphthyl‐cored stilbene derivative 11a exhibited promising fluorescence characteristics, highlighting its potential as an epoxy based fluorescent material for sensing applications.