: Use 3D modeling to prove that an intramolecular displacement reaction is possible despite the "long distance" seen in a flat representation.
Migration of a sigma bond across a pi system (e.g., Cope, Claisen). Practice Problem 3: Thermal vs. Photochemical Ring Opening
Propose a detailed, step-by-step mechanism for the rearrangement of a sterically hindered carbocation under acidic conditions, explaining the stereochemical outcome.