With control by N1-substituents, the switchable divergent C−H functionalization reaction of quinoxalin-2(1H)-ones is achieved for the synthesis of (Z)-enaminones and furo[2,3-b]quinoxalines using the combination of a copper catalyst and an oxidant. This new protocol features mild reaction conditions, readily available materials, and a broad substrate scope. Gram-scale and mechanistic studies were also investigated. Furthermore, the desired products exhibited excellent antitumor activity against A549, HepG-2, MCF-7, and HeLa cells, which were tested by MTT assay.

An inexpensive electrochemical induction system was used for the efficient reductive defunctionalization of sulfoximines through a radical pathway. This practical and robust strategy could be used for the removal of the SN bond-directing group from various sulfoximines. The practicability of this method was demonstrated by its mild conditions, simple operation, one-pot procedure, gram-scale synthesis, and the undivided cell. Furthermore, preliminary mechanistic studies suggested that the reaction might proceed via a homocoupling reaction and a denitrification procedure.

A direct difunctionalization method of alkenes with quinoxalin-2(1H)-ones and sodium sulfonates toward sulfone derivatives has been developed under environmentally friendly conditions. This strategy represents an efficient and practical difunctionalization of olefins using water/aqueous media as a sustainable solvent. In addition, this transition metal-free reaction is high yield, and operationally simple, and in particular, proceeds under mild conditions to afford desired sulfones with high functional group compatibility.

An efficient and practical SO 2 insertion protocol of NH-sulfoximines with aryldiazonium tetrafluoroborates and DABSO toward N-sulfonyl sulfoximines has been developed under mildly basic conditions. This transformation features easy operation, readily available substrates, and mild conditions. A tentative mechanism is proposed, which indicates that the aryldiazonium tetrafluoroborates would be radical donors under standard reaction conditions. The aryl radical produced in situ from diazonium salts would be trapped by SO 2 to generate an arylsulfonyl radical and then undergo further transformation to generate the final N-sulfonyl sulfoximines.