A solvent- and metal-free synthesis of substituted
Chalcogen-Naphthalenes employing DMSO/I2 as an
eco-friendly catalytic oxidation system
Laís T. Silva*a, Juliano B. Azeredoa, Alisson R. Rosárioa, Antonio L. Bragaa
a
Laboratório de Síntese de Substâncias Quirais de Selênio, CFM, UFSC, Florianópolis – Santa Catarina,
Brazil
*[email protected]
Keywords: Organochalcogen, Naphthalenes, eco-friendly synthesis
INTRODUCTION
Organoselenium and organosulfur compounds have
been highlighted due to their interesting biological
properties like antioxidant activity against Alzheimer,
1
Parkinson, cancer and hypertension. Moreover,
naphthalenes are important intermediates for the
preparation of several molecules with biological
2
activity. For example, Michellamines are anti-HIV
3
and Korupensamines
are antimalarial drugs.
Therefore, the synthesis of chalcogen-naphthalenes
is very appealing in organic synthesis. In this work,
chalcogen-naphthalenes were synthesized using an
environmentally benign methodology, in the absence
of solvents and metals, under microwave irradiation
in a very shorts reaction times. In our methodology,
we employed equivalent amount of dimethyl
sulfoxide as oxidant and molecular iodine in catalytic
4
amount.
RESULTS AND DISCUSSION
In order to optimize the reaction condition, 0.5 mmol
of β-naphthol 1a and 0.25 mmol of diphenyl
diselenide 2a were used as standard reagents under
different amounts of iodine and dimethyl sulfoxide,
temperature, time and microwave power. So far the
best condition found for this reaction was 20 mol%
of iodine, 3 equivalents of dimethyl sulfoxide at 80
°C and 100 W, where the product 3a was obtained
in 83% yield (83% yield, Scheme 1).
Scheme 1. Optimized reaction conditions.
Figure 1. Chalcogen-naphthalenes synthesized in
this study.
CONCLUSION
In summary, it was developed a rapid, economic,
and eco-friendly methodology for the preparation of
chalcogen-naphthalenes, an interesting class of
compounds for therapeutic applications. These
compounds were prepared with reasonable yields in
few minutes, under solvent- and metal-free
conditions. Further tests are under study in our
research lab in order to obtain higher yields.
ACKNOWLEDGEMENTS
The authors thank
and UFSC for financial support.
-
REFERENCES
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under study, we did a series of reactions using
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16th Brazilian Meeting on Organic Synthesis – 16th BMOS – November 15-18, 2015 - Búzios, Brazil