Oxidant-Free Selective Synthesis of Functionalized Chroman-4-ones from ortho-Hydroxyacetophenones under HOAc/DMSO Conditions

Abstract A metal-free and oxidant-free acid-promoted DMSO activation and subsequent reaction is reported. In this protocol, two molecules of DMSO are activated by HOAc and serve as dual synthons which react with ortho-hydroxyacetophenones, affording 3-(methylthiomethyl)chroman-4-ones in moderate to good yields with high selectivity.