Abstract
Carbonyl compounds have been successfully converted into their corresponding dithiolane, dithiane, and oxathiolane derivatives using a catalytic amount of alumina sulfuric acid (Al2O3–SO3H) with excellent yields at room temperature in short reaction times under mild conditions. This simple method is a highly chemoselective procedure for protection of aldehydes in the presence of ketones, and the heterogeneous catalyst can be recovered and reused several times without any loss of its activity.
ACKNOWLEDGMENTS
We are thankful to the Sistan and Baluchestan University Research Council for the partial support of this research.
Notes
a Yields refer to the pure isolated products. All known products have been reported previously in the literature and were characterized by comparison of MP, IR, 13C NMR, and 1H NMR spectra with authentic samples.[ Citation11-22 ]
b Isolated yield after five cycles with reused catalyst.
c The reaction was performed under reflux conditions in acetonitrile as solvent.
a GC yield using n-octane as internal standard.
b The molar ratio of substrate 1/substrate 2/1,3-propanedithiol/catalyst was chosen 1/1/1.05/0.05 (g).