A Configurationally Stable Indenofluorene-Based Helical Diradicaloid

The synthesis and the optoelectronic, magnetic and chiroptical properties of a helically chiral diradicaloid have been reported. Dibenzoindeno[2,1-c]fluorene, the simplest configurationally stable chiral derivative of the family of the indenofluorenes, shows a low HOMO-LUMO gap and a moderate singlet-triplet gap. Enantiomers have been isolated and are configurationally stable. Electronic circular dichroism has been measured and dissymmetry factor calculated. Our experimental findings are supported by DFT calculations.