Visible-light photoredox catalyzed thioesterification of sulfoxonium ylides with elemental sulfur and α-ketoacids.

An efficient strategy for the construction of α-keto thioesters has been developed via photocatalytic one-pot three-component reaction of sulfoxonium ylides with elemental sulfur and α-ketoacids. The reaction proceeded smoothly at room temperature using elemental sulfur as a sulfurizing agent and generated a series of α-keto thioesters in moderate to good yields. The present photocatalyzed transformation involves a carbonyl thiyl radical-based thioester synthesis, which overcomes traditional methods that employ unstable and malodorous thiols or thioacids.