Oxidation of Sulfides with Hydrogen Peroxide Catalyzed by Vitamin B₂ Derivatives

Abstract

5-Ethyl-3-methyl-2′,4′:3′,5′-di-O-methylenedioxyriboflavinium perchlorate (1, DMRFlEt⁺ClO₄ ^–), derived readily from commercially available vitamin B₂ (riboflavin), exhibits high catalytic activity for the oxidation of organic sulfides with hydrogen peroxide. The reaction provides an efficient and selective method for the oxidative transformation of organic sulfides to the corresponding sulfoxides under mild conditions.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details.]

GRAPHICAL ABSTRACT

Keywords:

• H₂O₂ oxidation
• organocatalysis
• sulfides
• sulfoxides

ACKNOWLEDGMENT

This work was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

Notes

^a The reaction of sulfide (1 mmol) was carried out in MeOH (1 mL) in the presence of 1 (0.02 mmol) and a 30% aqueous solution of H₂O₂ (1.5 mmol) at ambient temperature.

^b Isolated yield.

^c 1 (0.01 mmol), 30% H₂O₂ aqueous solution (1.1 mmol).

^d CH₂Cl₂ (1 mL) was used instead of MeOH.