Synthesis, Density Functional Theory Band Structure Calculations, Optical, and Photoelectrical Characterizations of the Novel (9-Bromo-3-cyano-5-oxo-1,5-dihydro-2H-chromeno[4,3-b]pyridin-2-ylidene)propanedinitrile

Abstract

Ring transformation of 6-bromochromone-3-carbonitrile (1) with malononitrile dimer in basic medium furnished the unexpected (9-bromo-3-cyano-5-oxo-1,5-dihydro-2H-chromeno[4,3-b]pyridin-2-ylidene)propanedinitrile (2, BCOCPP). Density functional theory, theoretical investigation of the electronic structure, geometries linear polarizability ⟨Δα⟩ (Quadrupole moment), first-order hyperpolarizability ⟨β⟩ (Octapole moment), natural bonding orbital, molecular electrostatic potential contours, thermo-chemical parameters, harmonic vibration frequencies, the FT-IR spectrum of the compound (2, BCOCPP) in the solid phase was recorded, and time-dependent density functional theory calculations at the B3LYP/6-311G (d,p) level of theory, UV-Vis spectra, in both ethanol and dioxane solvents have been employed for compound (2, BCOCPP). The geometrical and energetic parameters have been extensively investigated to reveal the reason behind the selective formation of compound (2, BCOCPP), instead of expected product 3. The Coulomb-attenuating method-B3LYP and Corrected Linear Response Polarizable Continuum Model studied for theoretically obtaining the electronic absorption spectra in gas phase, ethanol, and dioxane, respectively, and indicate a good agreement with the observed spectra. The heterojunction based on BCOCPP showed phototransient properties under various illumination intensities that give the recommendation of the studied heterojunction in the field of optoelectronic device application.