[2+ 2] Photocycloaddition, cationic cyclocodimerization, and reductive ring enlargement were developed for the syntheses of [2. n]-,[3. n]-, and [4. n] naphthalenophanes, respectively, from α, ω-bis (vinylnaphthyl) alkanes as a single starting material. Using the exclusive syn selectivity of the former two methods, the room required for the intraannular naphthalene-ring rotation in the ring system is determined.
