Synthesis, photophysical properties and DFT studies of chalcones and their 2-methoxy-3-cyanopyridine derivatives

Abstract

Synthesis and photophysical study of fluorescent molecules is of utmost research interest due to their optoelectronic and sensing applications. Herein, we report the synthesis of chalcone derivatives (C1, C2) employing the Claisen Schmidt condensation reaction followed by heterocyclization to provide the cyanopyridine derivatives (CP1, CP2). The novel derivatives (C1, CP1, CP2) were characterized using FTIR spectrometry, 1H, and13C NMR. The derivatives (C1, C2, CP1, CP2) display absorption bands in the range of 300–400 nm corresponding to π-π* electronic transitions. In the solid state, molecules exhibit a broad-range excitation band for the same emission while in the solution phase, dual emission was observed for all the derivatives in the 450–570 nm spectral range that covers the blue-green region. While C1 and C2 have low photoemission efficiencies in solid and solution phase, CP1 and CP2 exhibit broad and high photoemission efficiencies in both the phases; they are suitable for optical materials and may find use in sensors and OLEDs.