A Simple and Efficient Method for Reduction of Sulfoxide Under Solvent-Free Conditions

Abstract

Benzyl DABCO bromide was found to be an efficient and mild reagent for the reduction of sulfoxides to the corresponding sulfide using sulfuric acid adsorbed silica gel under solvent-free conditions at room temperature.

Keywords:

• Reduction
• solvent free conditions
• sulfoxide
• sulfuric acid adsorbed silica gel

Acknowledgments

We are thankful to the Damghan University of Basic Sciences for support of this work.

Notes

^a Yield refers to isolated pure products.

^b Sulfoxide/benzyl DABCO bromide/H₂SO₄-silica (1:2:4 mmol).

^c The products were characterized from their spectral (IR and ¹H NMR) and comparison to authentic samples.

^a The reaction was carried out with 100 mol% of PhSiH₃ and with 0.3 mol% of PMHS and 5mol% of MoO₂Cl₂.

^b The reaction was carried out with 1.0 mmol of sulfoxide, 2 mmol of catecholborane, and 5 mol% of MoO₂Cl₂(H₂O)₂.

^c The reaction was carried out with 1.0 mmol of sulfoxide, 2.0 mmol of BH₃-THF, and 5 mol% of MoO₂Cl₂.

^d The ratio of sulfoxide:1,3-dithiane:TABCO (2,4,4,6-tetrabromo-2,5-cyclohexadienone) is 1:1.1:0.2.