Understanding and Modulating Indolyne Regioselectivities

Heterocyclic arynes hold much promise for applications in modern synthetic chemistry. One particular class of hetarynes is those derived from the indole heterocycle (i.e., indolynes). Indolynes can be generated under mild fluoride-based reaction conditions using silyltriflate precursors. Indolyne-trapping experiments provide access to benzenoid-substituted indoles in a controlled manner with synthetically useful yields. Regioselectivities can be predicted prior to experiments using simple calculations, ultimately allowing for the modulation of selectivities by careful design. This strategy has enabled a concise synthesis of indolactam V.