Synthesis and Characterization of Two Unsymmetrical Indenofluorene Analogues: Benzo[5,6]‑s‑indaceno[1,2‑b]thiophene and Benzo[5,6]‑s‑indaceno[2,1‑b]thiophene

The synthesis and characterization of two benzo-indaceno-thiophene compounds (anti-BIT and syn-BIT) are described. Two sequential Suzuki cross-couplings utilizing the halogen selectivity of this reaction permit modular assembly of unsymmetrical indeno­[1,2-b]­fluorene analogues. Analysis of their cyclic voltammetry and UV–vis spectra reveal that the optical and electrochemical properties of the BITs lie between those of indeno­[1,2-b]­fluorenes and indacenodithiophene.