Photophysical properties of izomeric N-chlorobenzyl substituted (E)-2' (3'-or 4')-hydroxy-4-stilbazolium chlorides in alcohols.
Phys Chem Chem Phys
; 13(15): 6981-91, 2011 Apr 21.
Article
em En
| MEDLINE
| ID: mdl-21409191
ABSTRACT
Absorption and steady-state fluorescence spectra of nine N-p-(m- and o-) chlorobenzyl substituted (E)-2'-(3' and 4')-hydroxy-4-stilbazolium chlorides belonging to the hemicyanine class of compounds were studied in extra dry alcohols of different polarity. Derivatives with 2'-hydroxy or 4'-hydroxy substituent in the benzene moiety of stilbazol molecule displayed negative solvatochromizm. On the other hand, the excited state decay of compounds with a 3'-hydroxy group in the benzene moiety was dominated by non-radiative processes in protic solvents. Solutions of each of the compounds are yellow in extra dry solvents, red in solvents with small amount of water and yellow again if more water is added. The absorbance and steady-state fluorescence methods were used to explain the protonation/deprotonation processes for N-p-chlorobenzyl-(E)-4'-hydroxy-4-stilbazolium chloride and its zwitterionic or quinoid form in 2-propanol responsible for these phenomena.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Phys Chem Chem Phys
Ano de publicação:
2011
Tipo de documento:
Article