Carbolong chemistry: nucleophilic aromatic substitution of a triflate functionalized iridapentalene.

The reactivity of the triflate functionalized iridapentalene 1, [Ir{CHC(CH2C(CO2Me)2CH2)CCCHC(OTf)CH}(CO)(PPh3)2]OTf, with C-, N-, O- and S-centered neutral nucleophiles was studied, leading to the isolation of a wide array of irida–carbolong derivatives. As an extension, a polycyclic complex with a rare six-fused-ring structure was constructed. This strategy provides a new route for the construction of functionalized metallaaromatic complexes, and the resulting iridacycles exhibit broad spectral absorption ranges, making them potential photoelectric materials.