Imidoyl sulfoxonium ylides are presented for the first time as potential precursors to generate α-imino metal-carbene intermediates and applied in direct C–H functionalization reactions catalyzed by [Ir­(cod)­Cl]2 (4 mol %) to provide 2-substituted indoles (up to 70% yield) in just one step. This class of sulfur ylide is successfully obtained from imidoyl chloride and dimethylsulfoxonium methylide (23 new examples in 45–85% yield) or by imino group formation from the corresponding β-keto sulfoxonium ylides and anilines in the presence of TiCl4 as a Lewis acid (9 examples in 33–94% yield).

Sulfoxonium ylides in recent years have proved to be versatile building blocks and have found applications in the synthesis of structurally diverse organic molecules. In this work, we report a new oxidative, molecular iodine-mediated transformation on sterically encumbered arylated sulfoxonium ylides, which give access to 1,2-dicarbonyl containing compounds. Twenty-six examples have been realized (47-92 % yields), with structural diversity modified at two key sites on the sulfoxonium ylide reactants. Furthermore, the protocol benefits from the use of inexpensive molecular iodine to mediate the oxidation and, from a sustainability viewpoint, short reaction times (30 minutes), ambient temperature, and ethyl acetate as a greener reaction solvent. Experimental studies also gave insight to the mechanism of the reaction, involving DMSO as an oxygen source.

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