Ring expansion or spirocyclisation of (phenylthiomethylene)cycloalkanes with aluminium chloride viaβ-thio carbocations
Abstract
The title reactions can be explained by Wagner–Meerwein rearrangement of α-thio carbocations (thionium ions) to β-thio carbocations; this unusual reactivity may be due to superelectrophilic activation by aluminium chloride.