Selective ortho C−H Cyanoalkylation of (Diacetoxyiodo)arenes through [3,3]‐Sigmatropic Rearrangement

We herein report a robust catalyst‐free cross‐coupling between ArI(OAc) 2 and α‐stannyl nitriles, aided by TMSOTf. The transformation introduces a cyanoalkyl group to the ortho position of ArI(OAc) 2 and simultaneously reduces the aryl iodine(III) to iodide, thus providing α‐(2‐iodoaryl) nitrile as the product. This transformation could be completed within 5 min at −78 °C and features superb functional‐group tolerance and efficient scalability. DFT calculations indicate that the formation of a ketenimine(aryl)iodonium intermediate and subsequent [3,3]‐sigmatropic rearrangement are involved as key steps.