A Novel 1,6‐Methano[10]annulene Derivative with Bisnorcaradiene Structure—Syntheses with Transition Metal Complexes

2,10-Bis(phenylethynyl)-1,6-methano[10]annulene, a compound with “parallel” triple bonds, reacts with [CpCo(PPh3)2] and 2,6-dimethylphenyl isocyanide via a metallacycle to provide the 1,6-methano[10]annulene complex 1, which has a bisnorcaradiene structure. In addition, the methylene bridge of a 1,6-methano[10]annulene derivative was cleaved under unusually mild conditions to afford the novel naphthalene derivative 2.