Rare 1,6-C-H insertion of naphthol- and anthrol-derived alkylidenecarbenes has been observed in modest yield. Reaction in deuterated solvent did not provide any evidence in support of a reaction mechanism that requires exchange of the migrating proton with solvent. The pyran-annelated aromatic products are formed only when opportunities for the more common 1,5-C-H insertion process are blocked.
- C-H insertion
- Peri position