440 M.M. Lakouraj et al.
4.1. General procedure for the oxidation of sulfides to sulfoxides
In a 25 ml round-bottom flask, to a solution of sulfide (1 mmol) in THF (4 ml), 35% H2O2
(1 equivalent) and CC (0.4 mmol) were added successively and the mixture was stirred mag-
netically at r.t. for the time indicated in Table 2. The progress of the reaction was monitored
by TLC. After completion of the reaction, solid CA precipitate was filtered and washed with
diethyl ether. The filtrate was neutralized by adding (10%) NaHCO3. The product was extracted
with diethyl ether (3 × 5 ml) and the combined extracts were dried (Na2SO4). The solvent was
removed under reduced pressure to give the corresponding pure sulfoxide. Further purification
was achieved by short-column chromatography on silica gel with EtOAc/n-hexane (1:2) as the
eluent.
4.2. General procedure for the oxidation of sulfides to sulfones
In a 25 ml round-bottom flask, to a solution of sulfide (1 mmol) in THF (6 ml), 35% H2O2 (2.5
equivalents) and CC (1 mmol) were added successively and the mixture was stirred magnetically
at r.t. for the time indicated in Table 2. The progress of the reaction was monitored by TLC.
After completion of the reaction, solid CA precipitate was filtered and washed with diethyl ether.
The combined filtrates were neutralized by adding (10%) NaHCO3. The product was extracted
with diethyl ether (3 × 5 ml) and the combined extracts were dried (Na2SO4). Evaporation of
the solvent under reduced pressure gave the corresponding pure sulfone in most cases. Further
purification was achieved by recrystallization from EtOH.
Acknowledgement
The authors are grateful to the Research Council of Mazandaran University for their partial financial support.
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