Copper‐ and Palladium‐Cocatalyzed Intramolecular C–H Functionalization/C–N Bond Formation: A Route to the Synthesis of Indoloisoquinoline Derivatives

A Cu and Pd bi-catalytic system is found to be very effective for the indole C2–H functionalization/C–N bond formation process.This is a unique reaction in which isoquinoline systems were synthesized from aldoximes rather than from ketoximes. During the reaction Cu(OTf)2 converts the aldoximes into the corresponding cyanides and indoloisoquinolines, but introduction of Pd(OAc)2 changes the outcome of the reaction significantly, by suppressing the formation of cyano products, thus giving exclusively indoloisoquinolines. A range of substituted indoloisoquinolines and aza-indoloisoquinolines are prepared in good to very good yields under air.