Samarium oxide as efficient and non-endangered metal for synthesis of sulfones from sulfides: an elemental sustainability concept

Abstract

Oxidation of sulfide to sulfone is a fundamental process to produce many important pharmaceutical compounds. Formerly, efficient methods have been reported for the synthesis of sulfones from sulfides. Yet some limitations were identified, such as the unbalance use of metal catalysts and expensive oxidizing agent, low reaction yields and production of by-products. In this current research, oxidation of sulfides to sulfones is described in the presence of samarium oxide (Sm₂O₃) along with hydrogen peroxide. The SEM image showed the crystalline morphology of the Sm₂O₃ as a cubic single phase (ICSD 98-001-2948) with a size distribution between 120 and 300 nm. In the recyclability experiment, Sm₂O₃ catalyst can be reutilized for five successive cycles and afforded the desired end-products in great yields (97–95%). This current work is vital, as the usage of non-endangered metals in organic transformation is geared towards achieving the elemental sustainability concept.

KEYWORDS:

• Green chemistry
• sulfones
• recyclable catalytic system
• samarium oxide
• non-endangered metal
• elemental sustainability

Acknowledgements

The authors would like to express their sincere gratitude to the Organisation for the Prohibition of Chemical Weapons (OPCW) (Project Account No: L/ICA/ICB-115/21) as well as the research infrastructures supplied by Universiti Malaysia Terengganu.

Disclosure statement

No potential conflict of interest was reported by the author(s).