5
08
H. Eshghi, N. Mirzaie/Chemical Papers 65 (4) 504–509 (2011)
0
.2
.15
.1
to the synthesis of other organic compounds. Whereas
VIII
compounds II–V and VIII showed visible absorption,
only compoundsII and VIII showed intense emission
spectra in 510 nm and 520 nm respectively.
II
0
0
III
V
References
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Fig. 5 shows the fluorescence emission spectra of
−
6
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Conclusion
In conclusion, a convenient and efficient procedure
has been developed for the synthesis of fluorescein
derivatives by condensation of some phenols and ph-
thalic anhydride using Fe(HSO4)3 under solvent-free
conditions. The simplicity, scale-up, along with the use
of an inexpensive, non-toxic, and recyclable catalyst of
an environmentally benign nature, are other remark-
able features of the procedure which can be extended
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