(2,1‐ a )‐Indenofluorene Derivatives: Syntheses, X‐ray Structures, Optical and Electrochemical Properties

Two novel fluorophores based on the (2,1‐ a )‐indenofluorenyl backbone, dispiro[fluorene‐9,11′‐indeno[2,1‐ a ]fluorene‐12′,9′′‐fluorene], (2,1‐ a )‐DSF‐IF and 11,12‐dihydroindeno[2,1‐ a ]fluorene (2,1‐ a )‐IF have been prepared through original and efficient synthetic approaches. After consideration of synthetic features, the structural, optical and electrochemical properties of these new blue/violet emitters have been studied in detail by a combined experimental and theoretical approach. The properties of the (2,1‐ a )‐DSF‐IF and (2,1‐ a )‐IF are also compared to those of their corresponding positional isomers based on the (1,2‐ b )‐indenofluorenyl backbone and those of related dispirofluorene heteroacenes.