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(Reference retrieved automatically from SciELO through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Photophysical properties of coumarin compounds in neat and binary solvent mixtures: evaluation and correlation between solvatochromism and solvent polarity parameters

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Author(s):
Leonardo M. Moreira [1] ; Mirian M. de Melo [2] ; Priscila A. Martins [2] ; Juliana P. Lyon [3] ; Ana Paula Romani [4] ; Lúcia Codognoto [6] ; Sandra C. dos Santos [6] ; Hueder P. M. de Oliveira [7]
Total Authors: 8
Affiliation:
[1] Univ Fed Sao Joao Del Rei UFSJ, Dept Zootecnia DEZOO, BR-36301360 Sao Joao Del Rei, MG - Brazil
[2] Univ Vale Paraiba UNIVAP, Inst Pesquisa & Desenvolvimento, Sao Jose Dos Campos, SP - Brazil
[3] Univ Fed Sao Joao Del Rei UFSJ, Dept Ciencias Nat DCNAT, BR-36301160 Sao Joao Del Rei, MG - Brazil
[4] Univ Fed ABC, Ctr Engn Modelagem & Ciencias Sociais Aplicadas, BR-09210580 Santo Andre, SP - Brazil
[5] Universidade Federal de São Paulo. Departamento de Ciências Exatas e da Terra - Brasil
[6] Univ Fed Pelotas UFPel, Ctr Ciencias Quim Farmaceut & Alimentos, BR-96160000 Pelotas, RS - Brazil
[7] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210170 Santo Andre, SP - Brazil
Total Affiliations: 7
Document type: Journal article
Source: Journal of the Brazilian Chemical Society; v. 25, n. 5, p. 873-881, 2014-05-00.
Abstract

This work studied the fluorescent and solvatochromic properties of coumarin and its derivatives aiming to contribute in the elucidation of the excited state behavior of the molecule in solvent mixtures. This approach has been developed through a set of measurements involving different solvent ratios, which present distinct dielectric constants. The excitation and fluorescence maxima were largely blue-shifted with increasing participation of the organic solvent and the Stokes shifts were unusually low in mixtures with lower solvent polarity parameter, Δf. The emission intensity of coumarin was extremely sensitive to the polarity and the different structural conformations of solvents. These results influenced the spectroscopic behavior and explain the deviation from the linearity of the Lippert-Mataga relationship. The use of fluorescence spectroscopy makes the understanding of the behavior of the systems studied when in the presence of different environments being extremely important for the identification and characterization of coumarin in different pharmaceutical formulations. (AU)