Acidochromic Behavior of Dibenzylidene Cyclohexanone-Based Bischalcone: Experimental and Theoretical Study

Abstract

Synthesis and characterization of substituted 2,6-dibenzylidene cyclohexanone-based bischalcone derivatives and their optimized geometries were investigated by density functional theory. The synthesized compounds were identified through ultraviolet–visible, Fourier transform infrared, and 1 H nuclear magnetic resonance spectroscopies and elemental analysis. Significant acidochromic behavior was observed for 2,6-bis(4-dimethylamino-benzylidene)-cyclohexanone 1e . This result is owing to the preferential protonation of the chromophoric N , N -dimethylamino group, that is, quaternary salt formation and deactivation of the resonance system. The result was consistent with computational studies where the protonation was favored by 211 kcal/mol in the gas phase. The compounds also showed solvatochromic behavior. The geometries of the synthesized compounds were optimized with B3LYP/6-311G+(d,p) and APFD/6-311+G(d,p) basis sets. The single point energy indicated that APFD/6-311+G(d,p) basis set gave the lowest energy of 445–655 kcal/mol for the studied bischalcone derivatives. Quantum chemical parameters were also calculated.

Synthesis, characterization and application of a novel polyazo dye as a universal acid–base indicator

“…Subsequently, azo groups were increased by adding N , N -dimethyl aniline in the terminal position and the SDMAPD 3 BS synthesized solution was presented at a bathochromic peak at 374 nm with a higher maximal coefficient of 5.54 × 10 6 M −1 cm −1 . 52 It is noteworthy to mention that the absorption coefficient and the band gap for the synthesized compound increased and decreased, respectively, by adding N , N -dimethyl aniline to modify the end unit of the synthesized polyazo dye. In addition, the optical band gap of SDMAPD 3 BS was estimated using eqn (1) to be 1.89 eV.…”

Synthesis, Structural, and Intriguing Electronic Properties of Symmetrical Bis-Aryl-α,β-Unsaturated Ketone Derivatives

“…The spectroscopic data were found to be in correspondence with the literature data. 22 M.P = 115–116 °C, 1 H NMR (400 MHz, CDCl 3 ) δ 7.84 (s, 2H), 7.52–7.48 (m, 4H), 7.46–7.41 (m, 4H), 7.39–7.35 (m, 2H), 3.00–2.93 (m, 4H), 1.86–1.78 (m, 2H). 13 C NMR (100 MHz, CDCl 3 ) δ 190.41, 136.96, 136.21, 136.00, 130.39, 128.61, 128.41, 28.48, 23.03.…”

2,6-bis(E)-4-methylbenzylidine)-cyclohexan-1-one as a Fluorescent-on Sensor for Ultra Selective Detection of Chromium Ion in Aqueous Media

“…1 H NMR: δ 7.78 (s, 2H,=CH), 7.46 (d, 4H, ArH), 6.94 (d, 4H, ArH ), 3.86 (s, 6H, 2CH 3 ), 2.92 (dd, 4H,J = 14.6, 2.7 Hz), 1.82 (m, 2H, CH 2 ) (Fig. S1) [22]. The IR (KBr) spectrum (ν cm − 1 ): 1626-1642 (C = C Ar), 3000 − 2930 (C-H asymmetric), 1710 (C = O) 3030, (C-H Ar) (Fig.…”