NLOphoric Red Emitting Bis Coumarins with O-BF2-O core - Synthesis, Photophysical Properties and DFT Studies

Abstract

The red emitting dyes were synthesized by employing coumarin core as a donor and boron-bonded coumarin as an acceptor. 7-(N,N-Diethylamino)-coumarin 3-aldehyde was reacted with 3-acetyl-4-hydroxy-coumarin, 7-(N,N-diethylamino)-3-acetyl-4-hydroxy-coumarin and 3-acetyl-4-hydroxy-1-methyl-quinolone to form the corresponding chalcones. The synthesized chalcones were though red shifted as compared to the parent coumarin, and were not emitting in red region. The BF2-complexation was used as a tool to introduce a red shift in the molecules. The BF2-complexes synthesized were found to be red emitting and show higher one photon absorption cross section. The solvatochromism shown by these dyes was studied in the light of solvent polarity parameters. DFT calculations were used to understand the photophysical properties of the synthesized dyes. NLO properties of the dyes were estimated by solvatochromic and computational methods. All the molecules synthesized were characterised with the HRMS and NMR spectral Analysis.

Fluorescent vinyl and styryl coumarins: A comprehensive DFT study of structural, electronic and NLO properties

“…[12][13][14][15] Past few decades have witnessed developments in terms of synthesis of a huge number of organic π conjugated molecules with suitable molecular design strategies for better NLO materials. 16 Many of these molecules bear donor and acceptor groups separated by a conjugated bridge (D-π-A) with a push-pull type of arrangement. [17][18][19][20][21][22] NLO materials with good thermal and photostabilities are of great importance in photonics.…”

Coumarins into Polyurethanes for Smart and Functional Materials

“…The physical properties of the coumarin ring has always aroused high interest for the scientific community, and proof of this is the wide variety of works devoted to this issue. A large number of the photophysical properties of coumarin motif, such as high thermal stability, high quantum yields and large Stokes shifts, have been studied by emission and EPR measurements [88], however in the polymer area the most important properties are related to their high capacity for UV light absorption and fluorescent character. Both properties are described in more detail below.…”

Electronic Structure, Optical Properties and Quantum Chemical Investigation on Synthesized Coumarin Derivative in Liquid Media for Optoelectronic Devices

“…Different methods namely stark splitting, electric-dichroism, electronic polarization of fluorescence and microwave conductivity are available in the literature for the determination of dipole moments in the excited-state, but the use of those methods are limited since those methods are equipment sensitive and also related to a very simple molecule. Nevertheless, the solvatochromic method is simpler and accurate compared above mention methods and also it gives a straight measure of the distribution of electrons in the molecule, photons causing excitation of electrons in a molecule resulting the charge distribution takes place which leads to a conformational change in the excited state [22][23][24]. Many of the researchers have intensively reported for the determination of ground and excited state dipole moments experimentally and theoretically, in different types of organic fluorescent compounds like indoles, purines, thiadiazole Nile red dyes, phloroglucinol, quinolones, coumarins, excite dyes, laurdan, badan, benzimidazolone, chalcones [25][26][27][28] etc.…”