Synthesis and DFT study of the spectral behavior of new 4‐hydroxycoumarins

Abstract

4-Hydroxycoumarins are compounds with a lot of applications as drugs and herbicides. They have very interesting spectral and chemical properties, which are investigated theoretically and experimentally. Some new 4-hydroxycoumarins with arylydene-␤-ketoester or arylydene-2,4-pentanedione side chain were synthesized by two step synthetic scheme. Their structure was characterized by UV-vis, IR, and 1 H NMR methods. The spectral behavior of the optimized structures of these compounds was reproduced by the hybrid DFT methods B3LYP and B3P86 with 6-31G** and augcc-pVDZ basis sets. Electronic excited states and vibrational frequencies were calculated. HF method was also used for comparison, because of the lack of electronic correlation. The theoretical spectra were compared with the experimental ones. A lot of compounds show good agreement between experimental and some of the theoretical data, especially obtained by aug-cc-pVDZ basis set.

The isotropic nuclear magnetic shielding constants of acetone in supercritical water: A sequential Monte Carlo/quantum mechanics study including solute polarization

“…Previous calculations of shielding constants of organic molecules have discussed the model requirements necessary for accurate descriptions. [62][63][64][65] For supermolecular systems, the use of DFT has shown to be a good compromise between accuracy and computational effort [40][41][42][43][44][45]63 allowing the explicit inclusion of several solvent molecules. In this work, we first use the B3LYP ͑Refs.…”

Synthesis and Inhibiting Activity of Some 4-Hydroxycoumarin Derivatives on HIV-1 Protease

“…The product of the Michael addition was 3-[(4-hydroxy-2-oxo-2 H -chromen-3-yl)(4-hydroxyphenyl)methyl]pentane-2,4-dione ( 12 ) [11], see Figure 5. …”

“…A reaction of 4-hydroxybenzaldehyde and 2,4-pentanedione was also performed in the same conditions as above mentioned. The isolated product was 3-(4-hydroxy)phenylmethylene-2,4-pentanedione ( 6 ) [ 11 ], see Figure 3 .…”

“…3-(4-Hydroxy)phenylmethylene-2,4-pentanedione reacted with 4-hydroxycoumarin at the refluxing and the presence of piperidine. The product of the Michael addition was 3-[(4-hydroxy-2-oxo-2 H -chromen-3-yl)(4-hydroxyphenyl)methyl]pentane-2,4-dione ( 12 ) [ 11 ], see Figure 5 .…”

Coumarin‐Rhodamine Hybrids – Synthesis, Photophysical Properties, NLO Properties and DFT Studies

“…[2,[31][32][33][34][35] Various computational methods using different hybrid func-tional and basis sets have been used to study the solvent effects on the photophysical properties of coumarin fluorophore with varied functionalities. [36][37][38][39][40][41][42][43][44][45][46] Recently, increasing applications of non-linear optical (NLO) materials in electronic, optoelectronic devices, optical information processing systems and data storage devices have attracted many scientists. [47][48][49] Unlimited possibilities to modulate the physical and chemical properties of organic dyes by tailored synthetic routes can be used to tune their desired NLO properties.…”