Bis(azuleno)pentalenes with Six Consecutive Odd-Membered Rings.

ABSTRACT: Non-alternant, non-benzenoid polycyclic hydrocarbons (PHs) exhibit unique optical and electronic properties distinct from their well-studied benzenoid π-conjugated counterparts. However, the synthesis of such π-systems, particularly those composed exclusively of odd-membered carbocycles, remains a significant challenge. Herein, we report the first synthesis of three diazuleno[a,e]pentalene derivatives (AP-1, AP-2, and AP-3), featuring fused five- and seven-membered rings, via a palladium-catalyzed homoannulation of o-alkynylazulenyliodide. These compounds possess a 24 π-electron system with six consecutively fused odd-membered rings in a 7-5-5-5-5-7 topology. Comprehensive characterization by X-ray crystallography, NMR spectroscopy, and theoretical calculations (ACID, NICS) reveals an elec

SUBMITTER: Jiang Q 

PROVIDER: S-EPMC12643335 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature